The evolutionary path of least resistance
Paleontologists typically reconstruct past behavior by assuming that function follows form. But there can be more than one function for a given form, and different forms can serve the same function. Deconstructing these relationships can be complicated. Here, we use an example from human evolution—markedly different tooth morphologies in early hominins—to show that insights about the underlying genetic architecture of form can help us to better infer function and deepen our understanding of evolution.