Multigene phylogeny of the Mustelidae: Resolving relationships, tempo and biogeographic history of a mammalian adaptive radiation

Abstract

Background: Adaptive radiation, the evolution of ecological and phenotypic diversity from a common ancestor, is a central concept in evolutionary biology and characterizes the evolutionary histories of many groups of organisms. One such group is the Mustelidae, the most species-rich family within the mammalian order Carnivora, encompassing 59 species classified into 22 genera. Extant mustelids display extensive ecomorphological diversity, with different lineages having evolved into an array of adaptive zones, from fossorial badgers to semi-aquatic otters. Mustelids are also widely distributed, with multiple genera found on different continents. As with other groups that have undergone adaptive radiation, resolving the phylogenetic history of mustelids presents a number of challenges because ecomorphological convergence may potentially confound morphologically based phylogenetic inferences, and because adaptive radiations often include one or more periods of rapid cladogenesis that require a large amount of data to resolve.

Updating the evolutionary history of Carnivora (Mammalia): a new species-level supertree complete with divergence time estimates

“…It is difficult to envisage a case of taxonomic misidentification in this instance, especially given the source of the data [66], although an accidental mix up among the samples cannot be ruled out. This same sequence, however, was also used in a later analysis by the same authors [67], with no ill effects.…”

“…[67] apart from the indicated polyphyly of Galictinae. Our analyses, however, generally reconstructed older divergence times across the group than those inferred by Koepfli et al .…”

Evolutionary and biogeographic history of weasel-like carnivorans (Musteloidea)

“…A comprehensive study of Mustelidae (Koepfli et al, 2008) provided insight into this family's historical biogeography, but the power of inference in that study was limited by the fact that the method used for ancestral-area reconstruction did not allow polymorphous characters, and therefore species distributed on two or more continents were assigned to one of them on potentially arbitrary grounds.…”

“…This estimate is close to the nDNA-based ages of 16.3 MYA 15.6 MYA (Eizirik et al, 2010), though the latter authors also obtained a younger date of 13.0 MYA using a second dating method. Other estimates of this divergence event inferred by the application of multilocus molecular dating are considerably older and include ~20.2 MYA based 20 on mitochondrial nucleotide and amino acid (Árnason et al, 2007) sequences, and 26.2-20.9 MYA based on combined nDNA and mtDNA sequences (Koepfli et al, 2008). We note that †Plesictis plesictis, whose approximate geological age (24 MYA) was used by Koepfli et al (2008) to constrain the age of Mustelidae in their chronological analyses, is a stem rather than crown mustelid , which may account for older dates recovered in their analyses.…”

“…Although our Bayesian biogeographic analysis supported Asia, the parsimony analysis yielded an equivocal result, while the ML analysis favored an area involving both continents. Previous ML analyses similarly resulted in equivocal ancestral-area reconstructions (Koepfli et al, 2008).…”