Seasonal Dissociation in Fossorial Activity between the Llanos' Frog Populations as a Survival Strategy in Arid Subtropical Environments

Abstract

Among amphibians, the fossorial habit is an evolutionary strategy to maintain their niches along space and time, avoiding hostile climate conditions. The fossorial frog Lepidobatrachus llanensis has evolved in temperate regions, adapted and distributed in arid subtropical environments, and is divided into two well-defined and isolated populations (northern and southern). In this study, we analyze if these two populations have adjusted their activity patterns (i.e., feeding and reproduction) as a strategy to retain their ecological niche characteristics along a semiarid latitudinal gradient. We modeled and characterized the ecological niches via Euclidean distance to the ecological niche centroid of the entire species under the false premise that the two populations are equally active throughout the year (i.e., annual niche). Then, we repeated the exercise considering the niches for the two populations (by estimating their real seasonal niche activity). We also performed comparisons between both populations via a similarity test. Our results suggest that both populations are active in similar climatic conditions but in different (dissociated) temporalities, suggesting that seasonal activity in fossorial species is a strategy to conserve their climatic niche in two different geographical areas across the year.