Do methods for predicting paleohabitats apply for mountain and insular fossil bovids?

A variety of methods have been developed to use bovid postcranial elements in the functional morphology approach to paleohabitat prediction.This study represents a first attempt at testing morphometric methods based on astragalus and phalanges on extant mountain-dwelling bovids and insular fossil bovids from Sardinia assigned to the so-called‘Nesogoral group’,already regarded as close to the Caprini tribe.We intended to answer the questions whether a classic four-habitats model could be successfully applied to extant mountain-dwelling bovids,and whether results obtained could support the hypothesis of a radiative evolution for the Sardinian bovids.Results obtained,on the one hand,highlighted some inadequacies of the method if not applied to African bovids;on the other hand,they stressed the difficulties of discriminating habitat preferences of Sardinian taxa only based on biometry of astragalus and phalanges.Nonetheless,statistical habitat predictions suggest the contemporaneous presence in Sardinia of bovids having about the same size,but inhabiting different environments,giving support to the hypothesis that Sardinian representatives of the genus Nesogoral originated from a still unknown ancestor by an adaptive radiation evolutionary process.

Lights and shadows in the evolutionary patterns of insular bovids

Endemic bovids are intriguing elements of insular faunas.The living species include the Japanese serow(Cap-ricornis crispus)and the Formosan serow(C.swinhoei),the tamaraw from Mindoro,Philippines,(Bubalus min-dorensis)and the anoas(B.depressicornis and B.quarlesi),2 species of dwarf buffalos endemic to Sulawesi,Indonesia.Fossil endemic bovids are only recorded in some Asian,North American and Western Mediterranean islands.Here we present a comprehensive overview of the changes in body size and evolutionary patterns ex-hibited by both extant and extinct insular bovids.Our appraisal indicates that each insular representative of Bo-vidae shows its own peculiar evolutionary model,albeit some parallel trends exist(e.g.reduction in body size,allometric changes in limb bones,alteration of the life history traits).Some changes in morphology(e.g.the simplification of horn cores,the increase in hypsodonty,the acquisition of a‘low-gear’locomotion),for in-stance,appear as common,albeit not general,patterns triggered by a combination of selective forces.Body size patterns support the‘generality of the island rule’and suggest that biotic interaction had/have a major role in in-fluencing body size evolution in these species,although in different ways on different islands.All things consid-ered,available evidence suggest that a major role in the evolution of insular bovids is played by the structure of the insular community,the nature of available niches and by the dynamics of ecological interactions.