tree of life
... that Charles Darwin used a tree of life model to conceptualise his theory of evolution?
... that <a href="./Charles_Darwin" id="mwAYc" rel="mw:WikiLink" title="Charles Darwin">Charles Darwin</a> used a <b id="mwAYg"><a href="./Tree_of_life_(biology)" id="mwAYk" rel="mw:WikiLink" title="Tree of life (biology)">tree of life</a></b> model <i id="mwAYo">(sketch pictured)</i> to conceptualise his theory of evolution?