Longstanding scientific efforts have been dedicated to answer why and how our particular intelligence is generated by our brain but not by the brain of other species. However, surprisingly little effort has been made to ask why no other species ever developed an intelligence similar to ours. Here, I explore this question based on genetic and paleontologic evidence. Contrary to the established view, this review suggests that the developmental hurdles alone are not high enough to explain the uniqueness of human intelligence (HI). As an additional explanation I propose that HI is normally not retained by natural selection, because it is, under most conditions, an intrinsically unfavourable trait. This unfavourableness, however, cannot be explained by physical constraints alone; rather, it may also be rooted in the same emotional and social complexity that is necessary for the development of HI. Thus, a major obstacle towards HI may not be solely the development of the required physical assets, but also to cope with harmful individual, social and environmental feedback intrinsically associated with this trait. Yet, although our intelligence is such a powerful and generally useful trait, it has never been paralleled in any other organism. As an explanation, we generally assume that our cognitive uniqueness results from the major difficulty in achieving the required level of developmental sophistication. And after billion years of competitive evolution, we humans were the first species advanced enough to surmount these difficulties and to accumulate all features necessary for achieving this higher intelligence. Here, I investigate this conjecture and its underlying assumptions. For this purpose, I deliberately and necessarily adopt a very narrow anthropocentric definition for human (or human-like) intelligence (HI) as “the intelligence that enables development of advanced technology-based societies like ours”. Within this definition, ‘intelligence’ does not only refer to ‘computing power’, but also to the full ensemble of cognitive and character traits required to reach such a state. This definition is specific for “HI”, formulated to fit the purpose of my manuscript. It should not be seen as an alternative definition for “general intelligence”. Evidence for such a trend is weak. While a global trend toward bigger brains has been observed in several instances, it does not hold true for all taxonomic levels. It is unclear if this trend, which is weak and concomitant with an increase in diversity and afflicted by exceptions, is the result of directed evolution or random drift. It also appears that this trend, if it indeed exists, is a much weaker driving force than are the forces that are linked to adaptation to a specific niche.First, underlying this conjecture is a worldwide trend toward ever higher levels of intelligence, a trend that reached a critical threshold in the Pliocene when HI was finally developed in humansHomo sapiens was the first to reach an HI-enabling level of developmental sophistication evokes a linear view of evolution that posits that basal forms develop into ever more advanced and intelligent organisms. However, paleontologic and genetic evidence shows that evolution is not an orderly step-by-step advancement; rather, it is characterised by consecutive waves of radiation of species (many of which become dead-end groups) into the same ecological niches. During this iterative process of consecutive adaptations, many sophisticated characteristics  evolved several times, successively and independently, in different species  than the aye-aye (Daubentonia madagascariensis) brain. Rather, the human brain is more or less a scaled-up version of a non-human primate brain. Its size and structure are principally the result of simply extending the high growth rate of foetal brains into early infancy. This prolonged growth was achieved by the modification of gene expression patterns of a few regulators, a common mechanism for species differentiation . Of course, the scaling-up of the primate brain did not linearly affect all components, and the enhanced increase of the neocortex was certainly key to generating HI. Yet, altering the gene expression pattern of a single transcription factor (Pax6) in mice to a human-like pattern suffices to obtain a primate-like increase in neural progenitors, notably basal radial glia, and ultimately in the number of neurons produced, which is thought to underlie the evolutionary expansion of the neocortex. Human brain performance was additionally boosted by slightly increasing the ratio of astrocytes to neurons, a tendency already observed in other higher mammals. This ratio present in humans is, however, similar to that seen in other primates. In terms of genetic modifications, the development of the human brain therefore appears to be based on extending already existing features through gradual and common mechanisms, rather than being the result of a genetic quantum leap.Compared to the brain structure and brain-body ratios of other animals, the human brain is, of course, exceptionally big and complex in terms of layered structure, interconnectedness and neuronal diversity. But is its structure unique and sophisticated enough to justify that our brain capacity was never paralleled through adaptation and convergent evolution? Accumulated evidence suggests that the answer is no. Neuroscientists have established that the brain structures of birds and mammals are never simple. The anatomical differences between species reflect the animals’ adaptations to a particular niche, not the lack of sufficient time for their brains to become more complex. These changes sufficed to produce a large and sophisticated nervous system in addition to profound morphological innovations for their vision, arms and embryogenesis, resulting in a dramatically increased cognition and behavioural richness in octopuses as compared to worms, molluscs and other lophotrochozoans. Thus, the emergence of our highly specific human cognition has been achieved through continuity on a genetic level, accessible in principle also to other species.Such genetic evolutionary mechanisms are not restricted to primates. For example, it was the expansion of a handful of gene families and genome rearrangements in an otherwise standard invertebrate gene background that allowed octopuses to produce profound morphological and neurological changes. Although the overall brain architecture differs, convergent evolution can produce obligatory neuronal adaptations in unrelated genera. For example, von Economo neurons, which have been related to complex social behaviour, have independently evolved in primates, whales, elephants and racoons. Because of neuroplasticity, such convergent evolution is even easier for the brain than for other organs. Accordingly, our particular intelligence is not based on unique characteristics; rather, it arises from a combination and enhancement of abilities found in other vertebrates. In fact, our large brains and particular intelligence appear to be independent of our ape phylogeny; rather, they result from convergent processes similar to those that produced avian and New World monkey brains. Taken together with the finding that in some cognitive tasks monkeys can be outperformed by other animals, including birds and even fish, scientific evidence does not support the unilinear view that only the brain structure of apes is suited to produce HI.Since the human brain originated through extensions of primate brain features, can HI originate only from the brain structure of apes (Hominoidea)? If this is the case, then apes would have had to evolve first before HI occurred, and this condition may help to explain the late and single occurrence of this type of intelligence. However, it was not only other primate species (such as capuchins), but also elephants, cetaceans and certain birds that independently evolved cognitive and social characteristics that are very similar to those of apes , despite having fundamentally different brain architectures. Could the unique development of HI in humans be explained by our species being the only one capable of coping with the high metabolic demand of a brain required for generating HI?Big brains are energetically costly organs. Moreover, because of its neuronal density and neuron/glial cell ratio, a human brain requires more energy than for example a rodent brain of the same size) do not require features that are only found in humans, making sufficient subsets of them also accessible to other species. Moreover, as the brain of an organism becomes bigger and more powerful, the enhanced cognitive capacities will increasingly enable this organism to implement strategies to enhance energy intake. The cognitive pay-offs of big brains should therefore allow alleviation of the associated energetic cost. In conclusion, while the high energy demand of an HI-capable brain is an important roadblock for the development of HI, the physical and intellectual strategies required to overcome this hurdle are not only accessible to the human body plan. And although the adaptations required to sustain a big brain are profound, they are paralleled, for example, by the metabolic and physical adaptations required for powered flight, which has evolved multiple times in different taxa ; external transformation of food to a more edible state ; more efficient use of existing food sources through simple tools and/or strategies ; adaptive genetic changes to improve the digestive system (and associated microflora), or to diminish body energy expenditure [such as changes in skin coating (e.g. fur or feathers) or locomotion ]; increasing foraging efficiency through intra-species organisation ; or shifting to habitats richer in high-protein food sources. A subset of these strategies was sufficient to provide the increased energy demand throughout hominid evolution , the complex compositional, hierarchical and recursive syntax, and the need to learn the complete language from scratch during an individual’s lifetime. It was therefore not the pre-existence of an articulate vocalisation, but only a physiological potential for it, that was sufficient for allowing the evolution of HI in humans.Adopting the particular viewpoint of this essay, we then have to ask whether the development of HI-supporting language would be possible for other species. Let us first consider the requirements for producing a sufficient vocabulary. On a purely anatomical or mechanistic level, a HI-supporting language might be any sort of expression not limited to speech  that can produce a sufficient vocabulary space. This requirement does not seem to be restrictive. Moreover, some evidence suggests that the increase in human brain size preceded the development of finely articulated speech. The process and the underlying neuronal circuits by which a young bird learns the songs from an adult ‘tutor’ show indeed strong parallels with speech acquisition in human infants on behavioural, neural and genetic levels. Moreover, common genetic key players have been identified, including theFOXP2 gene. The hierarchical combination of ‘words’ bears resemblance to semantic combinations in primate calls or compass headings in honeybees. It has therefore been suggested that the human language results from the combination of separate, pre-existing simple systems that may have evolved for other functional tasks.Let us now consider language syntax and acquisition with respect to human uniqueness. It has indeed been proposed that such properties of the human language are neither specific to language nor to humans: Already Darwin had recognized the similarity between birdsong and human speechIn conclusion, while the exact behavioural, neural and molecular links between language, intelligence and behaviour are still emerging and under debate, significant characteristics of human language appear accessible to other species, including non-primates, and are not tied to a specific brain anatomy or size. Thus, current evidence suggests that the capacity for developing a HI-supporting system of communication is not a feature strictly limited to humans or the human brain anatomy or speech production.en route towards HI), and (ii) to quantitate the likelihood for the occurrence of such an ensemble in one animal. Thus, we can only approximate this question by asking if the presence of HI-enabling features and capacities was uniquely found in early hominids. In other words, is HI development such a rare event because of a shortage of suitable candidate species?HI poses requirements to a candidate species beyond developing and coping with the appropriate brain anatomy, associated energy demands and language. For example, HI would be most useful in an organism that can use tools and has a complex social system that allows transmitting and accumulating acquired knowledge and culture. Importantly, these individual features synergise with each other e.g.,60 and . Many species of dinosaurs, Triassic archosaurs or marsupials were/are bipeds with free, articulate limbs, affording them great potential for tool use, many relatively small, birdlike dinosaurs, such asTroodon, possessed a grasping hand with an opposable digit, whereas dolphins use tools even though they have no limbs to grasp the tools. Child caring, intra-species communication and even cultural transmissions are documented not only in primates, but also other vertebrates (such as meerkats and fish) and maybe even in insects . Social complexity as a potential driver for enhanced brain size and social intelligence  has been reported in diverse non-human vertebrates  nor to mammals (more than 120 cases of tool use in 104 bird species have been reported). For example, despite having a smaller brain than chimpanzees and australopithecines,Homo floresiensis, the Indonesian small-bodied ‘Hobbit’ species, was capable of manufacturing tools as advanced as those produced byHomo species with a three times larger brain. Moreover, the complex cognitive abilities of some bird species  are produced by brains that are less than 10 g in weight. Thus, HI candidate species are not limited to those animals that have comparable sizes to humans.Finally, development of HI does not appear restricted to organisms with sizes similar to humans. Although the brain-to-body size  appears to correlate roughly with cognitive capacity, brains do not have to be above a particular absolute size to produce high levels of intelligenceIn summary, while it is currently impossible to evaluate the evolutionary likelihood for combining the required features into a HI-capable animal, it is clear that many organisms besides humans readily combined several characteristics that could support HI . During development towards HI, these characteristics can in principle be developed further, and completed, as it has been the case in our lineage. And although the combination of features found in early hominids before brain expansion  are not common, they are not unique either, and it is therefore unlikely that HI was developed only once because no other species would have been a suitable candidate.Homo sapiens. If HI were within reach of convergent evolution, as my survey suggests, then an intriguing possible explanation for the fact that HI nonetheless evolved only once would be that HI is normally an overall unfavourable feature that is sooner or later sanctioned by selection. Yet, the physical constraints associated with HI appear to be manageable, and the human body is not special enough to suggest that no other organism could have evolved to cope with those constraints. If there is an unfavourable aspect of HI, then it must arise from somewhere other than these physical constraints.According to the findings discussed above, the development of HI is not complex enough to fully explain that it has never been reproduced in any other species thanCebus monkeys and some birds), suggesting that it is an intrinsic hallmark of HI.Could it be that some of the same mental and behavioural characteristics that are necessary for the development of HI might become increasingly unfavourable as a species evolves towards HI, creating a negative feedback loop? There is certainly a positive correlation between the proximity of species to HI and the emotional and structural complexity of their individuals and societies . This correlation is apparent in species with very different brain structures and sizes  and in violent or lethal aggression . If a further increase in the monkey’s para-HI intelligence requires increasing the same behavioural and character features that cause counterproductive comportments, then the resulting negative feedback may block development of HI. Conversely, if a candidate species deviates too much from these characteristics, then HI may not result, despite a suitable cognitive power.Behavioural studies on capuchin monkeys may provide an anecdotal illustration of this concept. These New World monkeys independently evolved an intelligence with certain characteristics similar to that of great apes and humansHomo sapiens pays for language’. It has also been shown in animals and humans that the more polymorphic tri-nucleotide repeats are present in the geneHdh (which codes for the protein huntingtin), the higher the capacity of this gene to promote the neural tube formation required for complex brains, but also the higher the probability to develop fatal neurodegenerative Huntington’s disease. More generally, the genes regulating synaptogenesis and neuronal circuit formation have been associated with an increased risk of mental illnesses. Based on autism spectrum disorders, it was suggested that brain networks involved in HI-required cognitive skills, such as language and complex social behaviour, have less compensatory mechanisms, and are hence less robust, than more ancient biological functions. As a final example, the rise of complex diseases  has been linked to the rapid genetic, geographic, dietary and cultural changes associated with HI. The impact of neurological pathologies increases in high-cognition species, and cumulates in humans, where currently about one in four individuals is affected . The incidence of mental disorders continues to grow, and with it its individual, social and economic impacts . Accordingly, mental health costs are now the highest single source of global economic burden in the world. Thus, the increased instability and lability inherently associated with a trajectory towards HI might produce a negative feedback loop counteracting the evolution of HI.In humans, an illustration for the negative effects of HI-associated cognitive complexity is provided by the high incident of cognitive diseases. For example, schizophrenia has been suggested to be ‘the price that. The authors suggest that continuation of this pattern leads to a point where this technology is no longer beneficial or useful to the island macaques, ultimately leading to extinguishing of this technology.Additionally, there might be a different type of negative feedback loop intrinsic to HI—HI might simply allow a species to become so successful in exploiting food resources that these resources become exhausted. A non-human example is provided by long-tailed macaques living on islands in Thailand. These monkeys developed stone tools that allow foraging on shellfish. Over time, however, this technology is so efficient that the macaques severely deplete the shellfish populations on the islands. This triggers a feedback loop where diminishing prey size results in reduced stone sizeHomo sapiens. However, all other species that have radiated into high-intelligence niches have stagnated at sub-HI levels, often for many million years; only theHomo lineage has crossed this barrier in a very short time. The fact that no other species has reached HI appears unsatisfactorily explained by physical constraints of HI. A possible additional explanation may be that the main barrier towards HI is not only the development of the required physical assets, but also that negative feedback from social, behavioural and neuroanatomical complexity, as well as negative environmental feedback make the development of HI increasingly unfavourable.A specie’s intelligence is a multidimensional characteristic adapted to maximise the specie’s survival. My analysis suggests that the genetic adaptations required for development of HI might have been within reach of more species than onlyHomo overcome this barrier? I speculate that key features may have been that our brain originated very rapidly as an exaptation, not adaptation, together with an ensemble of favourable anatomical changes , in a species with extremely low population densities . This origin may have initially allowedHomo to develop the brain structure required for HI, while circumventing or sufficiently attenuating immediate negative feedback associated with the use of HI in a socially complex populous environment where intra-species competition is the biggest threat.How could. However, globally engaging in the actions required to change our current trajectory and achieve long-term sustainability appears contrary to human nature.However, as we are becoming overly abundant, and use our brain to its full potential to succeed within our complex societies, the negative side effects become increasingly challenging. Despite the development of psychological, moral, behavioural (‘self-domestication’), pharmacological and technological solutions, we are knowingly and consciously pursuing our unsustainable development that is rapidly destroying the resources upon which we critically dependNo data are associated with this article. This interesting article speculates that the reason that human-type intelligence has not evolved in animals other than humans is that, ultimately, human intelligence is evolutionarily maladaptive.  I believe the evidence supports the contention that human-type intelligence has many maladaptive aspects, but I am not convinced that the issue is evolutionary. Moreover, much depends on what one means by “human intelligence.” Perhaps the greatest problem with the article as it now stands is the definition of human intelligence. The definition in the article is “the intelligence that enables development of advanced technology-based societies like ours.” This definition of intelligence is nonstandard and appears to be idiosyncratic relatively to standard definitions in the literature on intelligence, which tend to emphasize ability to learn, to adapt to the environment, to reason, and to process information efficiently and effectively . The problem with the author’s definition is that, for most of human history, there was no serious technology, at least not in the sense discussed in the article.  If the goal of intelligence is to enable technology, then it has to be a recent one, not one that is evolutionarily-based. Technology as we know it today is too recent. Yet, the functions of intelligence actually do change over time  and are somewhat different as a function of culture and place . If technology is the goal, and so much of technology, as we now know, is destructive, it is no surprise that intelligence could be so dangerous, whether for evolutionary or other reasons.et al., 2020), cultural intelligence , and practical intelligence . Fourth, there is the literature on wisdom, suggesting that humans need to apply their intelligence toward some kind of common good in order to thrive and create a sustainable future for themselves . Finally, dystopian novels, such asBrave New World and1984, have shown how human intelligence can lead to catastrophe as well as to success. The argument that human-type intelligence is maladaptive fits into an existing literature, which is largely not cited.  Consider some examples. First, there are notions of intelligence that are simply different from the conventional one. For example, Sternberg , in speaking of “adaptive intelligence,” has argued that current human deployment of intelligence has become destructive not only to humans, but also to many other species. It is making the environment unsustainable for human life, a point with which the author apparently agrees. Second, there are broader notions of intelligence that suggest that the conventional view of intelligence is simply too narrow —that there are multiple intelligences that do not fit conveniently into a single notion of general human intelligence. Third, there are theories of different kinds of intelligence that suggest that the conventional notion simply misses important aspects of human functioning, for example, emotional intelligence , pharmacological and technological solutions, we are knowingly and consciously pursuing our unsustainable development that is rapidly destroying the resources upon which we critically depend. However, globally engaging in the actions required to change our current trajectory and achieve long-term sustainability appears contrary to human nature.” Unless intelligence is deployed more adaptively, the world and the creatures in it are at serious risk . The question is whether we want to create a future for our progeny over many generations, or rather for many generations of viruses, bacteria, and, inevitably, the ever-present cockroaches.Cambridge handbook of intelligence .  Cambridge University Press.Ang, S., Ng, K. Y., & Rockstuhl, T. (2020).  Cultural intelligence.  In R. J. Sternberg (Ed.),Frames of mind: The theory of multiple intelligences.  Basic Books.Gardner, H. (2011). Cambridge handbook of intelligence (pp. 916-939). Cambridge University Press.Greenfield, P. M. (2020).  Historical evolution of intelligence.  In R. J. Sternberg (Ed.),Grossmann, I., Weststrate, N. M., Ardelt, M., Brienza, J. P., Dong, M., Ferrari, M., Fournier, M. A., Hu, C. S., Nusbaum, H. C., & Vervaeke, J. (2020). The science of wisdom in a polarized world: Knowns and unknowns. Psychological Inquiry, 31(2), 103–133. https://doi.org/10.1080/1047840X.2020.1750917Cambridge handbook of intelligence .  Cambridge University Press.Hedlund, J. (2020).  Practical intelligence.  In R. J. Sternberg (Ed.),Cambridge handbook of intelligence . Cambridge University Press.Rivers, S. E., Handley-Miner, I. J., Mayer, J. D., & Caruso, D. (2020).  Emotional intelligence.  In R. J. Sternberg (Ed.),Advances in cultures and psychology . New York: Oxford University Press.Sternberg, R. J. (2012). Intelligence in its cultural context. In M. Gelfand, C. -Y. Chiu, and Y. -Y. Hong (Eds.),Journal of Intelligence, https://doi.org/10.3390/jintelligence7040023Sternberg, R. J. (2019a).  A theory of adaptive intelligence and its relation to general intelligence. Cambridge Handbook of Wisdom: Race to Samarra: The critical importance of wisdom in the world today.  In R. J. Sternberg & J. Glueck (Eds.),Cambridge handbook of wisdom (pp. 3-9).  Cambridge University Press.Sternberg, R. J. (2019b).  Introduction to theCambridge handbook of intelligence .  Cambridge University Press.Sternberg, R. J. (2020a).  The augmented theory of successful intelligence.  In R. J. Sternberg (Ed.),Cambridge handbook of intelligence (2nd ed.).  New York: Cambridge University Press.Sternberg, R. J. (Ed.) (2020b). Adaptive intelligence: Surviving and thriving in a world of uncertainty.  New York: Cambridge University Press.Sternberg, R. J. (2021). Review of General Psychology, https://doi.org/10.1177/1089268020985509.  Online Version.Sternberg, R. J., & Karami, S. (2021).  What is wisdom? A unified 6P framework.  ReferencesIs the topic of the opinion article discussed accurately in the context of the current literature?NoAre arguments sufficiently supported by evidence from the published literature?PartlyAre all factual statements correct and adequately supported by citations?PartlyAre the conclusions drawn balanced and justified on the basis of the presented arguments?PartlyReviewer Expertise:IntelligenceI confirm that I have read this submission and believe that I have an appropriate level of expertise to confirm that it is of an acceptable scientific standard. I thank Prof. Sternberg for his thoughtful comments and criticism. These comments add greatly to the discussion I was hoping to engage in, and I welcome that the F1000 format allows publishing them alongside the manuscript. Below, I have represented passages from the reviewer’s report in italics. My replies are below.[…] I believe the evidence supports the contention that human-type intelligence has many maladaptive aspects, but I am not convinced that the issue is evolutionary. Moreover, much depends on what one means by “human intelligence.” Perhaps the greatest problem with the article as it now stands is the definition of human intelligence. The definition in the article is “the intelligence that enables development of advanced technology-based societies like ours.” This definition of intelligence is nonstandard and appears to be idiosyncratic relatively to standard definitions in the literature on intelligence, which tend to emphasize ability to learn, to adapt to the environment, to reason, and to process information efficiently and effectively . I agree that my definition of “HI” is non-standard, and acknowledge that this definition is “deliberately and necessarily […] very narrow and anthropocentric” in my manuscript. Indeed, this definition is specific for “HI”, formulated to fit the purpose of my manuscript. It should not be seen as an alternative definition for “general intelligence”. The main purpose of my manuscript is to ask why our particular intelligence “has never been paralleled by any other organism”. To position this discussion, I needed a definition of human intelligence that captures its unique attributes. However, many aspects of human intelligence  are also identified in other animals. In fact, our human intelligence appears to be a mix of cognitive traits that are already present in other animals. This observation is understandable because our brain is genetically and mechanistically not fundamentally different from the animal brains from which it derives. It is only the increased complexity and size of the human brain that enhance many of these traits. I also agree with Prof. Sternberg that intelligence is multidimensional and cannot be reduced to a single quantifying entity such as the IQ . Hence, I chose the “development of technology-based societies” as the uniquely human hallmark of HI. Were we to discover life on another planet, then it would be this “technology” aspect of intelligence that we would take (rightly or wrongly) as an indicator for an alien species to be our equal in terms of intelligence.Sternberg, 2020a. To clarify that my purpose-built definition of HI is not a general definition of  intelligence I have added a sentence to the ‘Introduction’: “This definition is specific for “HI”, formulated to fit the purpose of my manuscript. It should not be seen as an alternative definition for “general intelligence”, and I now citeThe problem with the author’s definition is that, for most of human history, there was no serious technology, at least not in the sense discussed in the article.  If the goal of intelligence is to enable technology, then it has to be a recent one, not one that is evolutionarily-based. Technology as we know it today is too recent. Yet, the functions of intelligence actually do change over time  and are somewhat different as a function of culture and place . If technology is the goal, and so much of technology, as we now know, is destructive, it is no surprise that intelligence could be so dangerous, whether for evolutionary or other reasons. In my manuscript, I am following the proposition of S.J. Gould that the human brain is an exaptation, not an adaptation . Accordingly, advanced technology was not the evolutionary goal of HI—just as powered bird flight was not the evolutionary goal of feathers, which have evolved many million years before birds took off from the ground (doi: 10.1016/j.tree.2019.04.018). Of course, a bird would not be able to fly without feathers, just as humans would not be able to produce technology without their brains. Yet, just as flapping or gliding with enlarged and specialised feathers may have increased the chances of survival in the ancestors of birds, the enlarged and specialised brains may have done the same for early homo species, for example by enhancing tool use or the control of fire. Intriguingly, many bird species coexist, and many species from other genera have developed highly sophisticated adaptations to allow powered flight without feathers. Conversely, only humans have developed ”serious” technology, and only one human species survives today. Given that even complex beneficial features such as powered flight could arise many times during the past ~200 million years, why has no other species developed cognitive capabilities that ultimately produce an advanced technology?The argument that human-type intelligence is maladaptive fits into an existing literature, which is largely not cited.  Consider some examples. First, there are notions of intelligence that are simply different from the conventional one. For example, Sternberg , in speaking of “adaptive intelligence,” has argued that current human deployment of intelligence has become destructive not only to humans, but also to many other species. It is making the environment unsustainable for human life, a point with which the author apparently agrees. Second, there are broader notions of intelligence that suggest that the conventional view of intelligence is simply too narrow —that there are multiple intelligences that do not fit conveniently into a single notion of general human intelligence. Third, there are theories of different kinds of intelligence that suggest that the conventional notion simply misses important aspects of human functioning, for example, emotional intelligence , cultural intelligence , and practical intelligence . Fourth, there is the literature on wisdom, suggesting that humans need to apply their intelligence toward some kind of common good in order to thrive and create a sustainable future for themselves . Finally, dystopian novels, such as Brave New World and 1984, have shown how human intelligence can lead to catastrophe as well as to success. In my manuscript, I conclude that the development of the features needed to create HI (in my definition) is not “difficult” enough (in terms of converging evolution) to justify that no other species has ever paralleled our cognition. As a possible explanation for this conundrum, I then speculate that HI is an intrinsically unfavourable trait, meaning that “the same mental and behavioural characteristics that are necessary for the development of HI might become increasingly unfavourable as a species evolves towards HI, creating a negative feedback loop”. In my manuscript, I based the current maladaptiveness of HI (in humans) on scientific data and predictions that state that our path is unsustainable and will lead to the “destruction of the resources onto which we critically depend”. Hence, I have only cited (some of) these sources. Evidence for the unsustainable nature of our trajectory is accumulating rapidly, and I have now included the IPCC Sixth Assessment Report to add a most recent reference. The points raised by Prof. Sternberg are of course relevant, and I thank him for bringing additional aspects into this discussion. Indeed, given that our intelligence is so highly “adaptive” that it allowed us to invade and populate all continents, it is puzzling that our intelligence appears to be consciously maladaptive in the long run with respect to the environment that we have largely created ourselves. Homo sapiens is a great invasive species but lacks the wisdom to sustain itself, once there are no new territories to conquer? Is it the general nature of HI to destroy itself? This discussion extends beyond the focus of my manuscript (which is: are there intrinsic feedback loops that hamper the development of HI in other species?). Concerning the literature on the different types of intelligence, I refer to my first reply above that I hope justifies why I have chosen a specific ‘result-based’ definition of HI  for the purpose of this manuscript. The two dystopian novels deal with the author’s imaginations for how future societies contain intellectual or moral aspects of human intelligence/behaviour. Destruction of the environment was not yet an issue. With this new imminent threat to humanity in plain view, what would Huxley’s brave new world have been?I think there is good evidence that human intelligence can be maladaptive. We scarcely need laboratory experiments when we look at how humans have handled crises such as global climate change, pollution, pandemics, and income disparity.  But are the mechanisms gravitating against human intelligence in animals other than humans evolutionary? That is much less clear.  No other species has, to our knowledge, come close to destroying the environment in the way humans have. There is no evidence that, because they started destroying the environment, evolution of human-like intelligence stopped. Moreover, for an evolutionary mechanism to take hold, the maladaptive trait would likely interfere with reproductive capability, but the people who destroy the Earth are mostly professionals, from politicians to corporate leaders, who are largely past reproductive age.  By the time they succeed in destroying the environment, they are older. Serious mental illness, cited in the article, can interfere with reproduction, but it seems to apply to relatively small proportions of the human population. I agree with Prof. Sternberg’s comments and criticism above: I do not claim to have fully resolved the nature of the intrinsic negative feedback that I propose limits the development of HI in species. In fact, my main concern was to first acknowledge that “something” appears to be intrinsically limiting the development of HI in animals because producing the physiological framework for HI is not sufficiently “difficult” to justify that no other animal has ever reached it. As possible intrinsically limiting factors, I suggest the resulting fragilizing complexity (of organisms and the societies they form) and resource-depleting technology. I provide some illustrations of these concepts based on non-human animals  in my manuscript.H. sapiens, when compared to earlier homo species . Air/water pollution and mental health problems are reducing fertility. But are these evolutionary mechanisms rapid enough to change our brain and nature in time for a non-catastrophic transition? Probably not, alas. To tentatively explain that HI did evolve in humans, despite these intrinsically limiting mechanisms, I hypothesise that the human brain, and hence its HI capability, has developed rapidly as an exaptation in a low-abundance species, and thus has managed to circumvent these intrinsically limiting mechanisms. Will the same mechanisms now be able to push back future human descendants into a pre-HI stage? As mentioned in my manuscript, there are interesting signs of “self-domestication”, and the relative brain volume of humans appears to have been shrinking inAlthough I have some disagreements with the author, I agree that “Despite the development of psychological, moral, behavioural (‘self-domestication’), pharmacological and technological solutions, we are knowingly and consciously pursuing our unsustainable development that is rapidly destroying the resources upon which we critically depend. However, globally engaging in the actions required to change our current trajectory and achieve long-term sustainability appears contrary to human nature.”Unless intelligence is deployed more adaptively, the world and the creatures in it are at serious risk . The question is whether we want to create a future for our progeny over many generations, or rather for many generations of viruses, bacteria, and, inevitably, the ever-present cockroaches.deus ex machina—with amachina being created by the same technology, and adeus with the same nature, that put us (and the rest of the planet) in this dire situation. A rational person would bet on the cockroach. Unfortunately, rather than changing our ways to favour our progeny, we seemingly prefer not to change and rather wait for a The author's revision of the manuscript satisfactorily addresses all concerns raised. The responses open to the reader, together with the respective references added, provide a clear justification for the statements made and an insightful view on the process of thought that led to each statement.Is the topic of the opinion article discussed accurately in the context of the current literature?YesAre arguments sufficiently supported by evidence from the published literature?PartlyAre all factual statements correct and adequately supported by citations?YesAre the conclusions drawn balanced and justified on the basis of the presented arguments?YesReviewer Expertise:Spatial navigation, neuro-electrophysiology, behavioral psychology, consciousness, bodily self-awareness.We confirm that we have read this submission and believe that we have an appropriate level of expertise to confirm that it is of an acceptable scientific standard. The manuscript discusses the uniqueness of human intelligence (HI) despite its apparent evolutionary advantages. Although the theme has been tirelessly revisited by many authors, a new theory is offered, that higher intelligence is disadvantageous and kept from developing through negative feedback. The author briefly goes through the main molecular and ecological arguments for the appearance and advantages of high intelligence, showing that those are not especially uncommon or slow in evolutionary history. Therefore, none could fully justify the evolution of HI, suggesting it to be generally an unfavorable trait. The theory is well constructed and the references support the hypothesis. Despite that, there are a few points in the manuscript that warrant attention:Page 3 - "Brain size, structure, and complexity"In terms of genetic modifications, the development of the human brain therefore appears to be based on extending already existing features through gradual and common mechanisms, rather than being the result of a developmental quantum leap" . The example given a few lines before, of Pax6, as well as other well known genes, such as the human-specific ARHGAP11B, despite being relatively small changes, result in significant leaps in brain development. The later example of octopuses also seems to indicate a sudden change, from the moment molluscs lost their shells, which still supports the paragraph conclusion that the genetic mechanisms that allow intelligence are available to other species. The author affirms that "Page 5 - "Language and intelligence""It is therefore not the capacity for an articulate vocalization, but only a predisposition for it, that is essential to the evolution of HI"  and"current evidence suggests that the evolution of a HI-supporting language is not a feature strictly limited to humans or the human brain anatomy or speech production" . The conclusion is especially confusing when declaring "HI-supporting language" while the manuscript appears to state that language is not a prerequisite for HI. In general, this session is not clear about language being a requirement for the development of HI, a mere consequence of it, or something in between, with some contradictions. For example About the passage:"Let us now consider language syntax and acquisition with respect to human uniqueness. It has indeed been proposed that such properties of the human language are neither specific to language nor to humans " . The references cited  indicate that there may be a human-only syntax, either through universal grammar or simply an advanced form of syntax allowed by the human FLB.Page 7 - "Conclusion and outlook""the main barrier towards HI is not only the development of the required physical assets, but also that negative feedback from social, behavioural and molecular complexity, as well as negative environmental feedback make the development of HI increasingly unfavourable" . Despite mentioning the possible negative feedback from molecular complexity, I couldn't find any examination of it in the main text. For reference: I wonder if there is a link between HI and sexual selection. Although intelligence as a simple fitness indicator would be equally accessible to other animals as well, cultural and behavioral products could also have influenced mating preferences."there might be a different type of negative feedback loop intrinsic to HI—HI might simply allow a species to become so successful in exploiting food resources that these resources become exhausted"   and again on the conclusion"we are knowingly and consciously pursuing our unsustainable development that is rapidly destroying the resources upon which we critically depend" . Despite that, HI also generates powerful positive feedback with niche construction, in which the environmental changes produced by HI favor HI itself. Finally, the text mentions the possible negative feedback of niche construction: page 7,Is the topic of the opinion article discussed accurately in the context of the current literature?YesAre arguments sufficiently supported by evidence from the published literature?PartlyAre all factual statements correct and adequately supported by citations?YesAre the conclusions drawn balanced and justified on the basis of the presented arguments?YesReviewer Expertise:Spatial navigation, neuro-electrophysiology, behavioral psychology, consciousness, bodily self-awareness.We confirm that we have read this submission and believe that we have an appropriate level of expertise to confirm that it is of an acceptable scientific standard, however we have significant reservations, as outlined above. I thank Dr. Atsushi and Dr. Vieira for their time and efforts to critically evaluate my manuscript, and for their very constructive feedback. In the following I provide a point-by-point reply to their comments, outlining also the changes I have made to the manuscript. I hope that my explanations  and manuscript changes respond to the reviewer’s comments in a satisfactory manner. Should issues remain, I’d be happy to further discuss and integrate these.Reply to comment on Page 3 –“ Brain size, structure and complexity”In terms of genetic modifications, the development of the human brain, therefore, appears to be based on extending already existing features through gradual and common mechanisms, rather than being the result of a developmental quantum leap" . They note that the “relatively small changes [in genes] result in significant leaps in brain development.”The reviewers refer to my statement that "genetic quantum leap.”rather than being the result of aI thank the reviewers for this comment that identifies a poor formulation in my essay. Indeed, I argue (in agreement with the reviewers) that the apparently big anatomical and cognitive changes were caused by only relatively small genetic changes. Consequently, I have corrected the wording into: “Reply to comment on Page 5 - "Language and intelligence"this session is not clear about language being a requirement for the development of HI, a mere consequence of it, or something in between, with some contradictions”, and they give specific examples for this contradiction.The reviewers note that “                 My position is that ‘full-blown’ HI needs a powerful communication system; however, Australopithecines and very early homo forms did certainly not have the language necessary to produce modern legislation, Shakespearean theatre or comprehensive gene ontologies. Hence, although a powerful communication system is a requirement for HI, it can (and probably will) be developed while a species develops HI. I agree that some of my formulations lacked precision, and I have now amended the text to enhance the clarity of this message:development of HI-supporting language would be possible for other specieswe then have to ask whether the”.“pre-existence of an articulate vocalisation, but onlya physiological potential for it, thatwas sufficient for allowing the evolution of HIin humans”.“It was therefore not thecapacity for developing a HI-supportingsystem of communication is not a feature strictly limited to humans or the human brain anatomy or speech production.Thus, current evidence suggests that the”“I thank Dr. Atsushi and Dr. Vieira for pointing out the mismatch between references and statement in the passage “let us now consider language syntax […]47,48”. Indeed, these references should not have been mentioned at this position, because the references for this statement follow in the ensuing discussion (references 50-57). Therefore, in the revised version, I have deleted the references 47,48 at this position (they are still used in the preceding passage) and put a colon instead of the full-stop for additional clarity.Reply to comment on Page 7 - "Conclusion and outlook"Despite mentioning the possible negative feedback from molecular complexity, I couldn't find any examination of it in the main text.”. Indeed, in the initial version, ‘molecular complexity’ refers to the extension of protein-level amino-acid repeats that are linked to both, increased cognition, but also increased psychopathology. I gave the protein huntingtin as an example. However, I agree that such repeat extensions  are not adequately described as ‘molecular complexity’. Moreover, the genetics of mental illness are only emerging very slowly, with different studies often reaching different conclusions doi: 10.1038/d41586-020-00922-8). Hence, it is also premature for general correlations between complexity and psychopathology on a molecular level.The reviewers rightly ask: “https://doi.org/10.3389/fpsyt.2012.00072). My manuscript already refers to it in “HI as an intrinsically unfavourable trait”, p7, in the two sentences following the mentioning of huntingtin , and, at a more advanced stage, more attractive cultural/ornamental items. However, given the wide-spread occurrence of sexual selection across animal species, I don’t see how sexual selection would uniquely favour HI in homo, but not in any other species. Hence, while sexual selection might have an influence, this influence would not be specific enough to humans to justify that HI has only emerged in our lineage.The reviewers also ‘HI might […] allow a species to become so successful in exploiting food resources that these resources become exhausted"; and “we are knowingly and consciously pursuing our unsustainable development that is rapidly destroying the resources upon which we critically depend"]. The reviewers suggest that “despite that, HI also generates powerful positive feedback with niche construction, in which the environmental changes produced by HI favour HI itself.”In their final comment, the reviewers refer to my discussion on the possible negative feedback of niche construction. In particular, they refer to my discussion of data showing the unsustainable nature of HI in its current ‘implementation’ in modern humans, ultimately making HI a maladaptive feature [“In response, I argue that both statements do not contradict each other. Rather, they consider different effects resulting in this feedback mechanism.Niche construction theory states that acquired features that allow a species to favourably transform its environment can be selected for during evolution. If a species can use its intelligence to ‘consciously’ and favourably alter its environment, then this would certainly result in positive feedback for the development of HI. The dam-building beaver is an obvious example for ‘intelligent’ niche construction . Hence, I agree with the reviewers and existing literature (e.g. doi:10.1098/rstb.2010.0306) that ‘conscient’ niche construction can boost the development of HI. However, two aspects are important in the context of my essay:Additionally, if the competitive advantage and driving force of HI development lies in overcoming dependence of the environment 14enables favourable niche construction, then this advantage would profit many species, and hence is not a limiting factor , or. “).          Firstly, nothing indicates that the positive feedback between HI and the development of ‘conscient’ niche construction is limited to humans. Hence, niche construction would not explain the main focus of my manuscript, namely the uniqueness of HI in humans. To take into account the reviewer’s comments, and to directly clarify this point, I have added the general aspect of niche construction in my revised manuscript . However, as I note in my manuscript, available studies overwhelmingly conclude that these HI-enabled environmental changes are unsustainable because they are


Maternal obesity is a public health issue that could affect both women’s and children’s health. This qualitative study aimed to identify barriers to weight management of pregnant women with obesity and low socioeconomic backgrounds.The current qualitative study has been conducted using a grounded theory approach by analyzing data collected from in-depth interviews with clients of Tehran’s public health care centers for prenatal care. The criteria for selecting participants were excessive weight gain during the first two trimesters of pregnancy, low socioeconomic status, and willingness to share their experiences. A semi-structured guide consisting of open-ended questions was asked in a private room. Open, axial, and selective coding were applied to the data.Four main themes emerged from data, each of which has some subcategories: 1) personal factors , 2) pregnancy status (unintended and high-risk pregnancy), 3) interpersonal relationships and support , 4) socio-cultural factors/influences .This study provides an overview of the barriers to the weight management of pregnant women from low socioeconomic backgrounds. The results could help develop appropriate health strategies for low socioeconomic women with obesity. Also, health care providers for this group of women could use these findings as a guide to consider their conditions and background. Obesity in women of childbearing age has become an epidemic in recent decades. The prevalence of obesity in women is reported to be 15% worldwide . Do not Although obesity and lifestyle-related diseases in women are on the rise worldwide, the risk factors and barriers to weight management are not the same in different cultures and socioeconomic statuses , 9. It hMaternal obesity rates in Iran indicate shortcomings in current pregnancy health services , especiaThe current qualitative study has been conducted using a grounded theory approach. The criteria for selecting participants were excessive weight gain during the first two trimesters of pregnancy, low socioeconomic status, and willingness to share their experiences. Participants were among pregnant mothers who received their prenatal care services from public health care centers of Tehran. The main researcher communicated with potential participants to explain the intentions and process of the current research. If the participants agreed to partake in the study, an interview was scheduled. To acquire participants’ views, 25 in-depth interviews were conducted from August 2018 to February 2020. An interview protocol was developed, including a list of interview questions, the procedural level of interviewing, and a script of what should be said before and at the end of the interview, prompts for the interviewer to collect informed consent, and the essential demographic information. All of the interviews, conducted by the main researcher, lasted between 1 and 3 h. A semi-structured guide consisting of open-ended questions was asked in a private room, enabling respondents to sufficiently explain their personal opinions, perceptions, and experiences. First, each participant was asked to describe their perceptions of and experiences with the main factors determining their excessive weight gain process and the main barriers to proper weight management during pregnancy. All interviews were conducted, audiotaped, transcribed, and analyzed in Persian. A qualified bilingual individual, adept in the nutritional qualitative research’s professional terminology, validated the translation quality and conceptual equivalence to establish credibility.The ethics committee of the Research Institute for Endocrine Sciences, Shahid Beheshti University of Medical Sciences, approved the study. Participants provided written informed consent before the interviews, and explicit permission was sought for audiotaping.Based on the grounded theory approach, data collection and analysis were done simultaneously and through constant comparative analysis in the current study . Open, aIn this study, the data’s credibility and confirmability were established by prolonged, in-depth engagement with participants and member checking. Choosing participants from low socioeconomic backgrounds with different age groups, educational levels, and occupations contributed to a richer variation of the phenomena under study. To confirm dependability, three other researchers scrutinize the study. Results were also checked with some of the expectant mothers, who participated in the research, and they confirmed the fitness of the results as well. All research details, including procedures, actions, and decisions, were documented for auditing purposes.A heterogeneous group of pregnant mothers with different employment, education, and reproductive histories participated in the study Table . Figure Personal characteristics included four subcategories: unpleasant emotions and feelings, personal tastes/hobbies, workload and responsibilities, and history of diseases. Pregnancy characteristics encompassed two subcategories: unintended and high-risk pregnancy. Interpersonal relationships/support included two subcategories: lack of a spouse’s support and unhealthy role modeling of relatives. Socio-cultural factors/influences included three subcategories: social norms and values, lack of access to health services, and unreliable information channels.“I always feel a big sadness in my heart, three years ago my eldest daughter got cancer and died at the age of 14. I was mourning and had no motivation for living. Sometimes I overeat and sometimes have no appetite to eat” . Accordingly, another pregnant mother described her anxiety and its repercussions on her dietary intake: “Sometimes when I am nervous, I could not eat anything for three or four days, but then I eat a lot” . Based on the mothers’ statements, fear was another emotion that could affect their eating habits during pregnancy, especially in those who were a new bride or expecting their first baby: “I’m afraid of low blood pressure. My sister felt weakness during her pregnancy and once lost her consciousness. I don’t want to have a similar experience; so I eat a lot” . Accordingly, some mothers pointed out loneliness as a determinant of their lifestyle: “Most of the time I am alone, it has been five months since we immigrated and I have not seen my relatives. I try to entertain myself by cooking and eating” . Finally, some participants referred to the hate as another influential experience: “My husband and I have to live with my husband’s mother. Once, she told me that I am not allowed to cook in the house. Although my doctor advised me to eat more protein, I always have to leave the table hungry and instead eat junk foods such as biscuits in my room because I don’t want to see her. I hate her, and I would like to die and not see her; unfortunately, due to poor nutrition, I developed gestational diabetes and became very obese.” .In the current study, a group of mothers noted that their unpleasant feelings such as sadness, anger, fear, disgust, anxiety, and loneliness affected their lifestyle and consequently weight management during pregnancy. In this regard, a mother pointed out the loss of her daughter and the burden of grief as the main influential factor on her eating habits: I think I eat a lot. I can’t stop eating anything I find at home. . This overeating has been observed for some particular foods: “I eat a lot of bread. I am very interested in Lavash bread  that I even ate that with rice and pasta, I know it is not good but I can’t help it”  and could be intensified during specific activities: “I eat more and more sweets every day, especially while reading a novel or watching T.V.“ . Another participant emphasized her taste as the important factor for choosing high-dense calorie foods and increasing the risk of overweigh: “I like greasy foods. In general, my family and I hate dry food. I believe that oil-free food is for sick people, and I don’t want to eat it” .Some pregnant mothers pointed out overeating as the leading cause of their excessive weight gain during pregnancy: ““I work 18 hours a day standing up. I do not have time to eat and sleep at all because of the customers. I work with chemicals hair colors that smell bad, especially since I got pregnant. So, when I get home, I feel starving and eat a lot and, I fall asleep right away” . Another mother complained about her heavy and challenging job, which could affect her lifestyle and result in excessive weight gain: “I am in charge of cleaning a sports club. I have to clear the whole area of the club and wash the bathrooms and toilets and carry the heavy garbage every day. So, I become famished in the evening. When I go home every day, I must eat 5-6 eggs fried in butter or jam and butter with two bread loaves. At the end of the night, when my husband comes, I also have dinner with him “.In the current study, some pregnant mothers attributed their unhealthy eating habits to their job: “I have been very obese since childhood, like my mother’s family who are all obese” . In addition, those participants who had experienced a delay in pregnancy attributed their overweight to potential hormonal imbalance, which could negatively influence their weight management efforts: “We wanted a baby, but my prolactin hormone was high, I couldn’t get pregnant. My doctor said that your weight gain was due to hormonal changes. I told myself that whatever I did to lose weight was useless” . This situation was aggravated by infertility treatments: “My weight gain is due to the hormonal injections prescribed to treat my infertility. Doctors said weight gain would be normal in this condition” . Further to hormonal effects, passing a high-risk pregnancy also exacerbated factors such as a sedentary lifestyle and increased rest time: “I was completely resting during my pregnancy because I was undergoing IVF treatment and under the supervision of a medical team. Recently a nutritionist has joined because I have gained a lot of weight. Of course, I am in the last week, and I have swelling. Maybe that’s why.” That I don’t lose weight.“ . “The condition of the fetus was unsuitable. I saw spots twice. I have completely rested from the first months and gained a lot of weight” . Besides high-risk pregnancy, some mothers referred to their medical conditions as the main determinants of excessive weight gain during pregnancy: “I was thin before marriage. After marriage, I had severe headaches due to a series of mental and nervous problems, and then MRI revealed that my spinal channel was narrow in my neck. And I used melatonin because of my heart palpitations, so I was sleepy, and I had to overeat before taking my pills. Although I could prevent my stomachache, I gained 35 k” .Aside from the primary factors that emphasized mothers’ unhealthy lifestyle as the main determinant of their overweight during pregnancy, some of the mothers pointed out the pivotal role of their sustained genetic backgrounds: “Before I got pregnant, I weighed about 97 kilos, but now my weight is 115 kilos. I am not motivated to lose weight. To be honest, I intentionally did not eat properly to make the baby abort” . One of the mothers said: “Honestly, I did not intend to get pregnant quickly because my son is only 11 months old. I wish I got pregnant again at least five years after my first pregnancy because I was very overweight, and now I am pregnant again” . “I have two older daughters, and I did not expect to be pregnant again, but unfortunately, I got pregnant, and it was unintended pregnancy. At first, I tried very hard to have an abortion, but my doctor talked to me a lot. My conscience bothered me, and my husband did not want to; I am no longer able to lose weight after giving birth” .In the current study, a considerable number of mothers stated that they became pregnant unintentionally and lost their motivation to lose weight. This unpleasant situation distorted their diet, sleeping patterns, and daily activities, which resulted in more weight gain: “I have a lot of cultural differences with my husband. I was interested in studying and exercising, but my husband only cares about eating, and after a while, I became an obese woman who only cooks well. I have no motivation anymore” . Another mother spoke of her husband’s constant disregard for her: “My husband doesn’t see me at all, even if he sleeps next to me. It doesn’t matter if I’m fat or thin, happy or sad, I’m indifferent to him, and I’m having fun with the kids and cooking, and my pleasure is cooking delicious food and eating”. . Another mother said about strict rules set by her husband for doing outdoor activities as a result of his family’s traditional attitudes: “I would like to go to a good gym with a good coach to supervise my activities; however, my husband does not allow me and says, “Go to the park.”. Surprisingly, when I want to go to the park for walking, he says, “I said something, why did you take it seriously? Does a noblewoman go to the park alone? This manner comes from his inappropriate beliefs” . Another mother said her husband did not support her financially: “My husband is very stingy. If I need anything, I have to tell him many times to prepare it, especially the food ingredients, so when I go to my mother’s house, I crave a lot of food” . Another mother said her husband insisted that she eat nutritious food during pregnancy: “My husband is thrilled to be a father soon. He keeps telling me to eat walnut kernels, almonds, and figs and nutritious foods, and I’m getting heavier by the day” . “My husband also forces me to eat nutritious foods, and I get fatter day by day” . Some mothers attributed their weight gain and obesity to their husbands desires: “My husband likes my face to be fat, but whatever I eat, my body gets fat, but my face is thin. Now that I am pregnant, my face is swollen and he says you are magnificent” . Similarly, another mother stated: “My husband hates a thin woman, everyone says I want you to be fat and plump, then when he wants me to be like this, why torment myself, I can hardly lose weight” .In the current study, a number of participants referred to their marital dissatisfaction as the most critical barrier to weight control during their pregnancy. In this regard, some of them complained about their husbands’ ignorance and misbehavior, which have mainly been rooted in their different cultural backgrounds and resulted in motivation loss to a healthy lifestyle and weight control: “Honestly, when I’m with my family, I always eat and sleep, and I am pleased” . Another mother spoke of her friend’s advice: “I have a friend who tells me: “You are pregnant, and you have to eat as much as you want” . It can be said that mothers have the most significant impact on their pregnant daughters’ nutrition patterns compared to other people. “Cooking for me is desired by my mother. Since I have been pregnant, she has constantly been cooking delicious food for me. . “My mother says that natural food is the best. I used to buy dairy from the store, but now she makes cheese, yogurt, sheep’s butter, and sends it. I also use them, especially butter” . “My mother says that local oil is suitable for a pregnant woman, and you should eat it every day “.Most participants mentioned family and friends’ role as one of the most important underlying factors for their unhealthy eating habits. Some mothers believe that they eat more when they are with relatives and friends. One group attributed the cause to a sense of cheerfulness in communicating with loved ones. Another group said that others insisted on encouraging them to binge eating and reducing the activity: “In our city, this body shape is a sign of beauty and physical strength, and people do not label it as obesity “ and another participant stated: “Everyone says when the baby is a girl the body will be swollen, and you will look obese” . Also, some beliefs influenced participants’ food intake and eating habits, resulting in overeating during pregnancy. In this regard, a mother said: “Every time I have a stomach ache, I drink soda to digest food, and the pain quickly subsides”  and accordingly another pregnant mother said: “I have to eat a lot of fruit so that my body absorbs more vitamin because too much vitamin is perfect for the growth of the baby “.Besides personal and interpersonal characteristics that could affect weight management during pregnancy, some socio-cultural factors influenced mothers’ weight status. In this regard, some of the mothers referred positive attitude toward obesity which lead to a lack of desire to control weight: “To search for anything during pregnancy, I search the internet to make sure it’s not bad for my baby” . Also, another participant stated that: “During my pregnancy, many people told me to eat this and not to eat that, but I searched on the internet and ate it if it was useful” . In some cases, this obtained information was even preferred to specialists’ advice: “I search for Nini Site a lot, especially about the growth and evolvement baby or nutrition of during pregnancy, and there no need to see a nutritionist anymore.” .In the current study, most of the participants were dependent on the internet and browsed various websites to find answers for their questions: “The cost of a visit to a gynecologist is very high, and we cannot afford it, so I did not go to the clinic from the third month onwards. I went to a nutritionist in my first pregnancy, but now I get fatter because I could not go to a nutritionist. At the same time, some pregnant women in a good financial position are under the care of gynecologists, nutritionists, and dermatologists. They provide good and expensive vitamins and supplements, and this easily and without breaking their body control their weight during pregnancy. They go through times, but I have to endure these conditions, and I cannot lose weight.” . Another mother said about the importance of having free psychological services during pregnancy: “I cannot go to a psychologist or psychiatrist because it costs so much. Especially for a mother who is experiencing pregnancy for the first time, it is difficult to accept mental and physical conditions, especially to lose fitness or change her emotions, and improving my mental condition helps to improve my physical condition; even our husbands need psychological services on how to treat their wives during pregnancy properly” . Another participant spoke of non-compliance with health insurance obligations: “Unfortunately, health insurance does not cover most of the necessary medications and genetic testing, and it puts a lot of pressure on the family” .The economic burden and high cost of mental health services and medical services were among the factors that caused the most adverse conditions for most participants, forcing many mothers not to use these services, especially in cases such as expensive clinical services as well as the lack of free psychological counseling services for mothers in this period: The current study aimed to explore barriers to control weight gain during pregnancy in mothers with low socioeconomic backgrounds. Our results showed that the most prominent barriers faced by pregnant mothers could be considered into three individual, interpersonal, and community levels. Based on the participants’ statements, at individual and interpersonal levels, mothers’ unpleasant emotions, as well as inappropriate marital relationships, were the most critical factors contributing to excessive weight gain during pregnancy, which were affected by social norms and beliefs, access to health services and information.Regarding individual factors that could affect the weight gain process during pregnancy, the current results revealed factors related to both mothers’ characteristics and pregnancy status. Our findings showed that unpleasant emotions, eating based on appetite, and high workload as the predominant barriers to proper weight management in pregnant mothers at the individual level. These results are consistent with previous studies that suggested the determinants mentioned above as influential factors on expectant mothers’ lifestyles . Based oIn addition to personal characteristics, some of the current participants attributed their excessive weight gain to their pregnancy status. Pre-pregnancy overweight and the related hormonal imbalance were mentioned by current expectant mothers as obstacles to weight management. Consistent with our findings, a large body of evidence has been written on the adverse effects of pre-pregnancy overweight and its relation to women’s hormone profile and reproductive performance . Also, bBeyond individual factors, our results revealed the crucial effects of husbands, families, and friends on pregnant women’s lifestyles and weight management. Previous research has also shown that as spouses and people around expectant mothers could play a motivating role in leading a healthy lifestyle, they could negatively affect their nutritional habits and physical activity , 33. AccRegarding a broader extent than personal characteristics and interpersonal relationships, socio-cultural factors including social norms and beliefs, unreliable information channels, and lack of access to health services were identified as impediments to the weight control of pregnant women in the present study. As participants stated, their cultural context and some misconceptions about prenatal care led them to an obesogenic lifestyle. Our findings are consistent with the socialized actor theory, which assumes norms influence individuals’ choices by shaping their needs and preferences . While tThis is one of the first qualitative studies aimed to explore the main barriers to weight management in pregnant mothers with low socioeconomic backgrounds. The current findings make an excellent opportunity to understand expectant mothers’ perceptions and experiences regarding the mentioned barriers in different personal, inter-personal and socio-environmental levels in an Eastern-Mediterranean context. Volunteer participation, as well as pregnancy circumstances, resulted in some data gathering limitations. Also, selecting mothers from urban areas of Tehran does not reflect pregnant mothers’ experiences residing in suburban and rural areas. Further research is recommended in these areas.This study provides an overview of the barriers to the weight management of pregnant women from low socioeconomic backgrounds. Based on the conceptual framework that emerged from the current data, the most critical barriers to weight management in pregnant women from the lower socioeconomic classes are rooted in various factors at the individual, interpersonal and environmental-social levels. In this regard, careful attention to the most modifiable factors at all mentioned levels in the form of ecological models seems necessary. The present results can be the basis for designing the tailored models and, consequently, comprehensive programs to promote women’s health and safe pregnancy among vulnerable groups in Iran and similar societies.


Telehealth interventions could improve pre-exposure prophylaxis (PrEP) initiation and adherence in high HIV incidence groups such as young Black sexual minority men (BSMM). However, young BSMM remain distrustful of and underrepresented in clinical trials. Therefore, ethical and culturally responsive ways are needed to build trust and improve their participation in PrEP telehealth clinical trials.To bridge this gap, this study identified ethical and culturally responsive activities to build trust and improve participation of young BSMM in PrEP telehealth clinical trials.We obtained data from 7 virtual, synchronous focus groups that were conducted from April to August 2020 and consisted of 28 BSMM aged 18-34 years. Focus groups included a brief survey distributed online via Qualtrics followed by a virtual, synchronous focus group conducted via Zoom that lasted between 50 and 75 minutes. Focus groups were stratified by age (18- to 24-year-old participants and 25- to 34-year-old participants), outlined the components of an example PrEP telehealth randomized controlled trial, and included questions on domains of the study design—research motivations, study funding, recruitment activities, informed consent details, randomization, follow-up, and end of study activities. Participants were asked targeted questions regarding the ethics and trustworthiness of the study and ways in which researchers could gain their trust through the protocol used in the PrEP telehealth clinical trial.The focus groups included 2 groups of 18- to 24-year-old participants and 5 groups of 25- to 34-year-old participants. The mean age of participants was 27.2 years (SD 4.4 years). Of the 28 participants, 10 (36%) reported a bachelor’s degree to be their highest completed education level and 6 (21%) reported some graduate degree or higher to be their highest completed education level. Most participants  reported that they worked full-time and that they were single or not in a committed relationship . Most participants  reported that they used at least one drug before sex in the 6 months prior to the study. All participants reported that they heard about PrEP and 36% (10/28) were current PrEP users. Overall, the focus groups yielded themes related to the impact of researcher intentions, study funding, recruitment activities, informed consent details, randomization, and study team interactions during and after the study on trust and participation in the clinical trial.Medical and research mistrust persists among BSMM. This study identified several ethical and culturally responsive activities to build trust and improve participation of young BSMM in PrEP telehealth clinical trials. Future studies should assess the relative impact of implementing these findings on research participation in a PrEP telehealth clinical trial. To reduce disparity in the United States, it is crucial to improve participation of young Black gay, Black bisexual, and other Black sexual minority men (BSMM) in HIV pre-exposure prophylaxis (PrEP) telehealth clinical trials ,2. WithoTelehealth refers to the use of telecommunication technology to support long-distance clinical health care, health education, and health administration ,11. TeleMedical mistrust refers to the lack of trust in the motives of and treatment by individuals and organizations associated with health care institutions ,20. MediTo bridge this gap, this study identified ethical and culturally responsive study activities to improve participation of BSMM in PrEP telehealth clinical trials. History-based models of trust ,30 proviWe collected data from 7 virtual, synchronous focus groups that were conducted from April to August 2020 and consisted of 28 BSMM aged 18-34 years. Individuals were recruited using a combination of active and passive strategies. Active recruitment included contacting participants from other research studies who provided written consent to be contacted for future research. Passive recruitment included advertising the study on Craigslist and obtaining referrals from participants in the study. Eligibility for participation in the study was defined by the following criteria: self-identification as a Black or African American man, age between 18 and 34 years, self-report of HIV-negative status, report of oral or anal intercourse with at least one male partner in the previous 6 months, or self-identification as a gay, bisexual, queer, or non-heterosexual individual.Because of COVID-19, data collection for the focus groups was updated to a virtual, synchronous format for safety. Details of the protocol for conducting the virtual, synchronous focus group have been published . Focus gATLAS.ti Scientific Software Development GmbH). Themes were identified using an adapted “pile sorting approach” , I got a pill for that too. So it’s like, no, I don’t trust the shit, right. I don’t trust any of it anymore. And it’s not that I don’t trust the research behind it. I don’t trust the way the research is being presented.P4, 20:59… I’m not stupid, like, I understand there’s a business side to all of this shit. So I’m just wondering what the--even if the true intent is to help people, I’m wondering what the gag is. I’m waiting for the shoe to drop.P2, 22:31To that point both Green and Red’s point. Y’all got to be making a shitload of money that you can just give out $75 to us for a survey. It’s a nominal cost…And to Red’s standpoint, can there be good intentions behind it? Yes. Could the pill actually be working? Yes. But it’s kind of like, at what cost? What am I really giving away?P3, 23:31Yeah. Yeah. Give a piece of your liver just in case you get drunk and fuck.P4, 25:13These sentiments suggest a dissonance in attempts to identify altruistic intentions of funding PrEP clinical trials relative to the anticipation of maltreatment because of the profitability of positive outcomes.Participants across groups shared that they would have greater trust and interest in the PrEP telehealth clinical trial if the study was led by Black researchers. They mentioned that Black researchers would provide better care during the study and interpret findings better than non-Black researchers because the participants believed that Black researchers had greater investment in the overall wellness of BSMM. When asked how researchers could gain the trust of BSMM to increase their participation in PrEP clinical trial research, participants in a 25- to 34-year-old group agreed with the man who said,Well, I think we need to see more black queer men doing these research studies, and not necessarily the face of it but--but actually running them from the start also. So don’t just put a black face on there for, you know, image purposes or, you know, recruitment purposes, but actually have someone like us running the whole damn thing.P4, 01:09:05Why?Facilitator, 01:09:34Well, like I said, going back to like I was saying before, you know, in order for me to trust you, I have to feel like you have, uh, walked similar spaces that I have. So therefore, you can--you understand where I’m coming from when I’m telling you all this information about it.P4, 01:09:37When asked how non-Black researchers could gain trust, every group mentioned the need for non-Black researchers to be “involved in the community” and collaborate with community-based organizations, including the 2 groups that suggested that the race of the investigative team did not matter if they perceived that they “cared about us.” However, 1 person in a 25- to 34-year-old group said,I feel like it’s the wrong question to ask, “how can we get black folks to trust these white researchers to come and, and, [laughter] and, and get their personal health information,” right? I think the question really should be, “how can we find more black researchers? And how can we get more black doctors? And how can we set them up for success in areas where they’re able to actually reach out with their community, right?” Like, the solution is not necessarily to place white doctors in black communities. That’s an extra barrier. And as a researcher, I don’t know why you would wanna do that.P4, 44:28Although participants shared an overall willingness to participate in a PrEP telehealth clinical trial led by Black investigators, they also shared that researchers generally should demonstrate care for the overall health and wellness of BSMM and not just recruit them for research.Despite information on how a consent form would detail the risks and privacy measures involved, every group mentioned that informed consent forms should provide more explicit, thorough, and understandable details. Participants were hesitant to believe that all known adverse effects regarding PrEP would be sufficiently outlined in a consent form for a study that was classified as an experiment. Initially, the extent to which PrEP efficacy was a part of the effectiveness of the clinical trial was not clear. Moreover, participants suggested that informed consent forms should explicitly outline intentions to not cause harm to participants. For example, one young man in a 25- to 34-year-old group said that the consent form should say, “Please. Thank you. I will not hurt you,” which would be an example of the “care” for participants that BSMM suggested that researchers should demonstrate. Regarding data privacy, the older groups alluded to the need for consent forms to further describe “Who really gets access to my data?” They believed that their survey data and health history could easily be obtained by other researchers, clinicians, or pharmaceutical companies who were not a part of the study team.Participants across groups generally perceived that having a computer-generated process that randomized individuals into 1 of 2 groups was fair. However, 2 participants in an 18- to 24-year-old group mentioned that they would not participate in the clinical trial if they were randomized to a telehealth treatment group because they lived with their family members and would have privacy challenges. Some 25- to 34-year-old participants expressed preferences for the telehealth treatment arm because of the perception that it would be a better experience than the standard of care. Others did not want to be in an experimental telehealth arm because they feared that their data or laboratory information could be compromised because of the virtual format.The 25- to 34-year-old participants suggested that randomization in this study is not fair to low-resourced BSMM who may not be able to fully participate in a long-term virtual study. They agreed with the man who thought that randomization to receive telehealth did not account for a participant’s circumstance, specifically their ability to access a safe and private space to conduct a telehealth visit, to access a reliable internet connection, and to access technology.I don’t think it’s fair--only because I think you have to think of the wholeness of the situation. If you’re randomizing someone to the telehealth group, um, again, you have you have to see what type of resources that you have to give to them.P3, 36:24And they can privately be able to talk, you know? Because if they don’t, it shuts out a lot of people in the community. So if we--they want it to be truly open to all people that if someone were to want to participate in the study and they are homeless, and they’re assigned to telehealth. Then we can’t guarantee them a private space or we can’t guarantee that they have reliable internet connection. We can’t guarantee that they have access to technology. Some people just do not feel comfortable sticking a needle in themselves, or whatever other, activities they need to further participate on their own. So I think that that’s why the, the randomization, I think it’s challenging, um, because there’s so much more in consideration with this community.P3, 36:40Although only a few participants within the groups mentioned this, group members agreed that researchers could prevent a substantial subgroup of BSMM from participating in the telehealth clinical trial by not allowing them to choose their group assignment.Participants suggested that the research team  should introduce themselves and conduct occasional wellness check-ins with participants regardless of race during interim study visits to build trust along the course of the study. They suggested that this type of communication would demonstrate “care” and investment in the overall health of BSMM. When asked to provide examples of how the research team should communicate with participants during the study, the 25- to 34-year-old participants said,I believe that the researchers should make themselves available and present. I don’t think they necessarily be at every single transaction throughout the course of the project. But they need to have, like, check-ins or midpoints and touchpoints ‘cause that’s the whole point. So, like, just even a follow-up like, “Hey, thanks for coming out, really appreciate what you’re doing.” Just, just something to let the people know that you actually care. Like, treat them like humans because if I only see you at the beginning of the orientation and at the end when it’s all over, I’m gonna feel some kind of way because I feel like he didn’t really care about me as a person.P4, 56:26Okay. Does that go for a researcher of any demographic or--?Facilitator, 56:58Any demographic.P4, 57:08Yeah. I feel like you should still reach out because I feel like you have to be more personal. If you didn’t, then, I mean, I probably would never do a study with you again.P3, 57:24The 18- to 24-year-old participants said,I guess email contact, maybe text messages, or maybe emails.S2, 36:57How often?Facilitator, 37:06Whatever the person is more comfortable with. I guess you just follow up, weekly or monthly or however you feel is necessary.S2: 37:06Yeah, I think being in touch and also letting them know that you are there for their safety and their health, that, yeah, they’re going through a study, but ultimately, it’s for their health and their well-being. Um, so being able to check on their health and their well-being, their mental health, you know, um, as well while they’re doing the study just lets them know that, “Okay, you’re committed to making sure that I'm given the support I need while helping you out.” Because we’re helping each other out, basically.S3, 37:22The 25- to 34-year-old participants explicitly mentioned that PrEP should be provided for free during the study as part of the incentives because of the low prevalence of adequate insurance coverage among BSMM. They suggested that it was unreasonable to expect participants in the study to pay for the medication along with the laboratory fees associated with PrEP care and that $50 cash incentives per visit would not be sufficient or equitable. When asked if providing larger cash incentives was coercive, participants across all the groups believed that cash incentives were more equitable for their time and participation in the study. The following is an example,So what are y’all thoughts on monetary incentives for PrEP research? Like do you think people are being exploited when you give cash?Facilitator, 48:28No.P2, 48:43No.P4, 48:44No. I mean it’s mutually beneficial to both parties, you know? I don’t think that that’s exploitative.P2, 48:46I mean people naturally want to get paid for the time, whether that be with money or some other form of incentive. So I don’t think it’s exploitative.PS2, 48:59Some participants also shared that participation in PrEP telehealth clinical trials was a way for some BSMM to obtain medical or financial support via clinical care and cash incentives.Like I was saying before, a lot of people don’t have the resources to have insurance. They can’t afford insurance, some of them are only working part-time jobs. Or multiple part-time jobs that don’t pay a lot in the first place. So I think it’s kind of unfair to require that…maybe this research study is the only way I have to acquire this medication, acquire these resources because I can’t afford the insurance.P4, 55:57Um, I think that if you’re doing this on research, if you wanna include especially like LGBTQ people, gay people--P3, 57:05Young.P2, 57:18--then you should, you should, in that research program, find a way to provide, health care for free for at least a year. You know, some kind of--I don’t know. I know that’s a lot of work to get done, but I just feel like a lot of people in our community don’t have access to health care. So if that’s a requirement, then you’re gonna be missing out on a lot of the people that, you know what I’m saying--P3, 57:19Right.P4, 57:28Participants across focus groups understood that PrEP telehealth resources would end with their participation and mentioned that it would be fair if the consent form explicitly stated that they would not be receiving the same resources after a specified amount of time. However, participants in the 25- to 34-year-old groups suggested that ending the convenience of PrEP telemedicine was not fair and would lower their trust and interest in future PrEP telehealth clinical trials. When asked whether not being able to have the telehealth treatment after the study ends is fair, one person said, “No. What the fuck? You can’t get me used to something for a whole year and then just take it away.” Others in the younger group said,Not being able to have the services would definitely be, troubling if you just came to a study, and you were being helped, but now, all of a sudden, now your insurance is no longer being, paid for.P2, 44:50What do you think about being referred to another clinic for standard PrEP care once the study is over but you couldn’t get telemedicine?Facilitator, 45:14At least you will be providing them, at least referring to somewhere where you can still get your medicine, even if it’s not telemedicine.P2: 45:24I’m kinda thinking about my earlier comments about, like, you know, there’s an office there? I think it would kinda be hard for people who have been--for a year--had the support they needed, and they’re being cut off at the end of that year. So, I don’t know. I think it’s a tricky subject. I think that what they need to be sure is just to make sure they know at the end of this trial they may not have all of the support they used to have in that one year.P3, 45:34Participants viewed the study as a service provided to the community for their benefit, not necessarily an experimental treatment for a specific amount of time. They mentioned that collaborating with community-based organizations that could potentially continue similar services after the study increased their interest and trust in the study.This study explored culturally responsive study activities to build trust and improve the participation of BSMM in PrEP telehealth clinical trials. Overall, PrEP telehealth was an acceptable intervention strategy among BSMM. However, source of study funding, researchers’ cultural congruence, intentions, and interactions, along with treatment assignment and ending telehealth impacted trust and study interest among BSMM. Medical and research mistrust persists in this population. The findings suggest that mistrust in PrEP telehealth clinical trials may persist because underlying issues regarding ethical clinical research conduct for minority groups have not been sufficiently addressed for BSMM. This study allows a reassessment of the traditionally acceptable domains of ethical research conduct to build trust and improve participation of BSMM in PrEP telehealth research.The trust that BSMM have in PrEP telehealth clinical trials was assessed in part by their perception of how other and low-resourced BSMM may be treated or disregarded in the study. Concerns about the potential experiences of other in-group members is an important domain of history-based models of trust. Specifically, trust, according to this framework, is impacted by participants’ own, vicarious, or anticipated experiences ,30. CumuThis study also revealed themes that established elements of care for BSMM throughout the PrEP telehealth clinical trial protocol and greater trust in a trial led by Black investigators. Other studies have found similar themes along the lines of establishing “care” to improve trust among BSMM ,26,32. SThemes regarding the fairness of randomization to telehealth treatment groups and ending telehealth services suggest that BSMM assumed that the experimental treatment arm was inherently better than the standard of care and this impacted trust in the researchers and study. The assumption that one research group in a randomized controlled trial benefits more than the other undermines the presence of equipoise and raises questions regarding the ethical considerations of PrEP telehealth randomized controlled trial protocols . Some reImportantly, we also found that information typically documented in an informed consent form  was noted as unfair and insufficient. Guided by the Belmont Report , informeThe limitations of this study should be considered. This study did not quantify the prevalence of medical mistrust in this sample. Additionally, this convenience sample may have been biased toward a favorable attitude to PrEP telehealth generally because of participation in the virtual, synchronous focus group. Information from participants who were unwilling or unable to participate in the virtual focus group could have impacted the range of identified themes in this study. However, data from those participants are unavailable.Overall, this study still provided important ethical and culturally responsive considerations for improving participation of BSMM in PrEP telehealth research. Given the salience of medical mistrust in the group, future studies should quantify the prevalence of these domains in the attitudes and willingness to participate in a PrEP telehealth clinical trial among BSMM. Future research should also assess the relative impact of implementing these findings on research participation in a PrEP telehealth clinical trial.