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Habitat use affects morphological diversification in dragon lizards.
D C Collar1, J A Schulte, B C O'Meara
1Department of Organismic and Evolutionary Biology, Harvard University, Cambridge, MA 02138, USA. dcollar@oeb.harvard.edu
Journal of Evolutionary Biology
|March 30, 2010
Summary
Dragon lizards in different habitats show varied diversification. Ground-dwelling lizards diversify more readily than those living in trees or on rocks, influencing their limb and body evolution.
Area of Science:
- Evolutionary biology
- Comparative morphology
- Ecology
Background:
- Habitat structure influences species diversification and evolutionary trajectories.
- Dragon lizards (Agamidae) exhibit diverse ecomorphologies across various habitats.
Purpose of the Study:
- To investigate how different structural habitats affect the diversification of limb and body form in dragon lizards.
- To determine if habitat use (rock-dwelling, terrestriality, semi-arboreality, arboreality) correlates with evolutionary rates of morphological traits.
Main Methods:
- Phylogenetic analysis of 90 dragon lizard species.
- Ancestral state reconstruction to infer habitat use.
- Fitting evolutionary models to morphological trait data (size and shape).
Main Results:
- Multiple lineages independently evolved similar habitat uses.
- Rock-dwelling and arboreal habitats were found to limit diversification compared to terrestrial and semi-arboreal habitats.
- Slower rates of size and shape evolution were observed in rock-dwelling and arboreal lineages.
Conclusions:
- Habitat specialization, particularly in trees or on rocks, can impede ecomorphological diversification.
- Ground-dwelling (terrestriality) appears to facilitate greater evolutionary differentiation in dragon lizards.
- Habitat structure is a significant factor shaping evolutionary patterns in lizard morphology.
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