Data from: Trophic niche drives the evolution of craniofacial shape in Trinidadian guppies

Diverse clades of fishes adapted to feeding on the benthos repeatedly
converge on steep craniofacial profiles and shorter, wider heads. But in
an incipient radiation, to what extent is this morphological evolution
measurable and can we distinguish the relative genetic vs. plastic
effects? We use the Trinidadian guppy (Poecilia reticulata) to test the
repeatability of adaptation and the alignment of genetic and environmental
effects shaping poecilid craniofacial morphology. We compare wild-caught
and common garden lab-reared fish to quantify the genetic and plastic
components of craniofacial morphology across four populations from two
river drainage systems (n=56 total). We first use microCT to capture 3D
morphology, then place both landmarks and semilandmarks to perform
size-corrected 3D morphometrics and quantify shape space. We find a
measurable, significant, and repeatable divergence in craniofacial shape
between high predation invertivore and low predation detritivore
populations. As predicted from previous examples of piscine adaptive
trophic divergence, we find increases in head slope and craniofacial
compression among the benthic detritivore foragers. Furthermore, the
effects of environmental plasticity among benthic detritivores produces
exaggerated craniofacial morphological change along a parallel axis to
genetic morphological adaptation from invertivore ancestors. Overall, many
of the major patterns of benthic-limnetic craniofacial evolution appear
convergent among disparate groups of teleost fishes.