fierce debate
...that despite over a hundred years of scientific study, fierce debate still rages about how arthropods' heads are constructed?
...that despite over a hundred years of scientific study, <b id="mwCUc"><a href="./Arthropod_head_problem" id="mwCUg" rel="mw:WikiLink" title="Arthropod head problem">fierce debate</a></b> still rages about how <a href="./Arthropod" id="mwCUk" rel="mw:WikiLink" title="Arthropod">arthropods</a>' heads are <a href="./Segmentation_(biology)" id="mwCUo" rel="mw:WikiLink" title="Segmentation (biology)">constructed</a>?