EVOLUTION OF PAEDOMORPHOSIS IN PLETHODONTID SALAMANDERS: ECOLOGICAL CORRELATES AND RE-EVOLUTION OF METAMORPHOSIS. (1st February 2014)

• Record Type: Journal Article
• Authors: Bonett, Ronald M.; Steffen, Michael A.; Lambert, Shea M.; Wiens, John J.; Chippindale, Paul T.
• Is Part Of: Evolution. Volume 68:Number 2(2014:Feb.)
• Page Start: 466
• Page End: 482
• Publication Date: 2014-02-01
• Subjects: Amphibians -- biogeography -- climate -- development -- life history -- phylogeny; Evolution -- Periodicals; Heredity -- Periodicals; Évolution (Biologie) -- Périodiques; Hérédité -- Périodiques; 338.47004094
• DOI: 10.1111/evo.12274
• Languages: English
• ISSNs: 0014-3820

Abstract

Abstract: Life-history modes can profoundly impact the biology of a species, and a classic example is the dichotomy between metamorphic (biphasic) and paedomorphic (permanently aquatic) life-history strategies in salamanders. However, despite centuries of research on this system, several basic questions about the evolution of paedomorphosis in salamanders have not been addressed. Here, we use a nearly comprehensive, time-calibrated phylogeny of spelerpine plethodontids to reconstruct the evolution of paedomorphosis and to test if paedomorphosis is (1) reversible; (2) associated with living in caves; (3) associated with relatively dry climatic conditions on the surface; and (4) correlated with limited range size and geographic dispersal. We find that paedomorphosis arose multiple times in spelerpines. We also find evidence for re-evolution of metamorphosis after several million years of paedomorphosis in a lineage of Eurycea from the Edwards Plateau region of Texas. We also show for the first time using phylogenetic comparative methods that paedomorphosis is highly correlated with cave-dwelling, arid surface environments, and small geographic range sizes, providing insights into both the causes and consequences of this major life history transition.