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Geographical distribution and ecological diversification of S outh A merican octodontid rodents
Author(s) -
Ojeda A. A.,
Novillo A.,
Ojeda R. A.,
RoigJuñent S.
Publication year - 2013
Publication title -
journal of zoology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.915
H-Index - 96
eISSN - 1469-7998
pISSN - 0952-8369
DOI - 10.1111/jzo.12008
Subject(s) - biological dispersal , biology , biogeography , vicariance , ecology , evolutionary biology , diversification (marketing strategy) , philopatry , phylogenetics , phylogeography , demography , population , biochemistry , marketing , sociology , gene , business
Caviomorph rodents represent one of the most distinctive groups of mammals in southern S outh A merica drylands; they colonized S outh A merica from A frica via trans‐oceanic dispersions in the E ocene (40–50 Ma ) and underwent an extraordinary ecological radiation after their arrival, thus making this group of great interest for biogeographic and evolutionary studies. The aim of this article was to provide a working hypothesis regarding the biogeographical history and ecological diversification of one of its conspicuous families, the O ctodontidae. We reconstruct the evolutionary theater where their ecological diversification took place, and potential events of dispersal, vicariance and extinctions. We analyzed the historical biogeography of the O ctodontidae across the eight ecoregions where they occur, based on species phylogeny and divergence times. Four approaches were used to reconstruct ancestral area: (1) S tatistical D ispersal– V icariance S nalysis ( S ‐ DIVA ); (2) B ayesian binary Markov chain Monte Carlo (MCMC) analysis implemented in R econstruct A ncestral S tate in P hylogenies ( RASP ); (3) F itch optimization method; and (d) weighted ancestral area analysis ( WAAA ). Parsimony ancestral state reconstructions were implemented in order to explore the evolutionary history of an ecological character, mode of life. We propose the northern portion of the M onte desert ecoregion as the ancestral area in the evolution of the O ctodontidae, with subsequent dispersal and enlargement of the family geographic range. The evolution of their ecological specialization (i.e. modes of life) suggests an ambiguous ancestral condition (saxicolous, generalist terrestrial, semifossorial) linked to species adaptation to arid environments, with fossoriality appearing later in octodontid evolution. The evolution of the O ctodontidae is associated with contrasting environmental conditions (i.e. climate and vegetation) produced by the A ndean U plift between eastern and western sides.