Life history strategies are decoupled from ecomorphological convergence in two Anolis lizards

Abstract

Convergence is considered powerful evidence for adaptation to similar natural selection pressures. However, for many ecologically and morphologically convergent species, it remains unclear if convergence extends to reproductive strategies, which are particularly important because of their tight connection to fitness. Here, by measuring key life-history traits (e.g., reproductive status, egg size, oviposition frequency, reproductive effort) across a full annual cycle comprising both reproductive and non-reproductive seasons, we discover divergence in reproductive strategies in two Anolis lizards that are otherwise strikingly convergent in ecology, morphology, and behavior. The Cuban brown anole (A. sagrei) rapidly produces many small eggs during a concentrated summer reproductive season, while the Puerto Rican crested anole (A. cristatellus) produces comparatively fewer, larger eggs over a longer period. Thus, despite evolving highly convergent ecomorphological phenotypes and both being constrained to a single-egg clutch, these species exhibit marked divergence in life-history trade-off strategies along the fast-slow continuum. Our results indicate that ecomorphological convergence evolved uncoupled from life-history pathways in these species.