Evolution of ecological structure of anole communities in tropical rain forests from north-western South America

Abstract

The coexistence of several anoles in the same place is attributed to differential partitioning of resources. Although several mainland and island communities show a similar structure, differences in life-history traits, absence of niche complementarity, higher food supply and higher numbers of predators in mainland environments support the idea that predation, rather than competition, is a more important structuring force in mainland than in island anole communities. To analyse the pattern of ecological structure in mainland anole communities, we studied communities in three tropical rain forests of north-western South America to obtain data about the use of resources on three niche axes [spatial, thermal and morphological (as a proxy of diet)] for 17 species of anoles. We analysed the patterns of niche overlap for each axis and found that overlap on the dietary axis was less than the overlap on the other axes, indicating that species using similar spatial or thermal resources diverge strongly in their diet. In addition, we identified a niche complementarity among niche axes, suggesting that intraspecific competition is also an important process in those communities. Finally, this study revealed a similar ecological structure in different communities of mainland rain-forest anoles, which share seven ecomorphs, suggesting ecological adaptation and convergence in mainland anoles.

Claws and toepads in mainland and island Anolis (Squamata: Dactyloidae): Different adaptive radiations with intersectional morphospatial zones

“…A comparable pattern of unique regional and convergent peaks between mainland and Greater Antilles anoles can be seen also in ecological features of 17 mainland species (Moreno-Arias et al, 2020); we included all of these species in this study. Similarly, Yuan et al (2020a) suggest that differences in morpho-ecological relationships in the roquet and bimaculatus series can be explained, in part, by their different phylogenetic origin.…”

“…To evaluate the relationship of claw and toepad morphology and perch dimensions (i.e., the characteristics of diameter and height of the branch and trunk occupied by the lizard), we compiled data of height and perch diameter for 23 species of mainland Anolis (Irschick et al, 1997a; Moreno‐Arias et al, 2020; Phillips et al, 2019; Velasco & Herrel, 2007) (Table 1). We transformed perch variables and body size; since perch diameter and height were not related to body size, we employed perch dimension log data.…”

“…Additionally, we classified species according to habitat use as reviewed in Moreno‐Arias and Calderón‐Espinosa (2016) and ecological information recorded for 17 species in Moreno‐Arias et al (2020). Two species groups were defined according to their microhabitat use.…”

“…These ten morphotypes differ mostly in body size, hindlimb length, and relative number of lamellae. They may also differ in vegetation use and behavior, as suggested for 17 mainland species evaluated by Moreno-Arias et al (2020). Compared to Greater Antilles ecomorphs continental morphological diversity appears higher and includes some morphological groups that are exclusive to the mainland, although some mainland species resemble to the Greater Antilles ecomorphs (Huie et al, 2021;Moreno-Arias et al, 2020;Moreno-Arias & Calderón-Espinosa, 2016;Velasco & Herrel, 2007).…”

“…They may also differ in vegetation use and behavior, as suggested for 17 mainland species evaluated by Moreno-Arias et al (2020). Compared to Greater Antilles ecomorphs continental morphological diversity appears higher and includes some morphological groups that are exclusive to the mainland, although some mainland species resemble to the Greater Antilles ecomorphs (Huie et al, 2021;Moreno-Arias et al, 2020;Moreno-Arias & Calderón-Espinosa, 2016;Velasco & Herrel, 2007). However, Poe and Anderson (2019) analyzed 336 species, including island and mainland Anolis, and found that each radiation had a similar number of morphotypes; and like Moreno-Arias and Calderón-Espinosa (2016), observed that there were exclusive morphotypes for each radiation (islands and mainland).…”