Decoupling in Diversification and Body Size Rates During the Radiation of Phyllodactylus: Evidence Suggests Minor Role of Ecology in Shaping Phenotypes
Por:
Ramirez-Reyes, Tonatiuh, Velasco, Julian A., Flores-Villela, Oscar, Pinero, Daniel
Publicada:
1 sep 2022
Categoría:
Ecology, evolution, behavior and systematics
Resumen:
Empirical studies have shown that several taxa exhibit a decoupled
relationship between lineage species diversification (the balance
between speciation and extinction) and phenotypic diversification. This
has been recognized by some authors as fundamental evidence for
non-adaptive radiation. In the leaf-toed geckos Phyllodactylus of North
America, there is a wide inter-specific overlap of phenotypic traits and
high intra-specific morphological variation, despite predominantly
allopatric distributions and the colonization of both insular and
continental habitats. Here we demonstrate two outstanding aspects of the
evolution of Phyllodactylus-first, that the radiation occurred with rate
decoupling (body size and diversification), and second, that the
contributions of island colonizations to the genus' diversification
(phenotypic and species) have been of the same magnitude as those of
continental habitats. Phyllodactylus diversification has proceeded with
minimal ecological influence, as suggested by the identification of
limited phenotypic diversity, evidenced by the wide representation of
one morphotype (shared in island and mainland environments) and limited
disparity (body size and shape) for long periods of time. Conversely,
some head traits like snout length have increased in disparity in recent
times. Most likely, snout length is being shaped by selective pressures
associated with the differential exploitation of insular and continental
trophic niches. The decoupling of rates (diversification and body size
evolution), long periods of morphological stasis (body size and shape),
overlapping of traits in the morphological space, and minimal ecological
influence on the evolution of body size suggest that Phyllodactylus has
proliferated following the tempo and mode of a non-adaptive radiation.
Filiaciones:
Ramirez-Reyes, Tonatiuh:
Univ Nacl Autonoma Mexico, Fac Ciencias, Museo Zool, Ciudad Univ, Ciudad De Mexico 04510, Mexico
Univ Nacl Autonoma Mexico, Inst Ecol, Dept Ecol Evolut, Ciudad De Mexico 04510, Mexico
Velasco, Julian A.:
Univ Nacl Autonoma Mexico, Inst Ciencias Atmosfera & Cambio Climat, Ciudad Univ, Ciudad De Mexico 04510, Mexico
Flores-Villela, Oscar:
Univ Nacl Autonoma Mexico, Fac Ciencias, Museo Zool, Ciudad Univ, Ciudad De Mexico 04510, Mexico
Pinero, Daniel:
Univ Nacl Autonoma Mexico, Inst Ecol, Dept Ecol Evolut, Ciudad De Mexico 04510, Mexico
|