Evolutionary history of mental glands in turtles reveals a single origin in an aquatic ancestor and recurrent losses independent of macrohabitat.

摘要: Despite the relevance of chemical communication in vertebrates, comparative examinations macroevolutionary trends signaling systems are scarce. Many turtle and tortoise species reliant on signals to communicate aquatic terrestrial macrohabitats, many these possess specialized integumentary organs, termed mental glands (MGs), involved production chemosignals. We inferred evolutionary history MGs tested impact macrohabitat their evolution. Inference ancestral states along a time-calibrated phylogeny revealed single origin ancestor subclade Testudinoidea. Thus, represent homologous structures all descending lineages. also multiple independent losses both clades. Although first appeared an (the testudinoid ancestor), seems have had little effect MG presence or absence descendants. Instead, we find clade-specific trends, with some clades showing increased gland size morphological complexity, whereas others exhibiting reduction loss. In sister inhabiting similar ecological niches, contrasting patterns (loss vs. maintenance) may occur. conclude that not been influenced by other factors affected