
Phylogeny and biogeography of liverbearers (genus Brachyrhaphis; figure credit: Ingley et al. 2015).
Biogeography is the study of patterns in distribution of fish (or other) species. Biogeography provides an understanding of where populations are currently present and can help infer evolutionary relationships at a broad scale, including historic population isolation and colonization events. Geologically, many species patterns can be tracked with plate tectonics. The study of biogeography can also complement understanding of current ecological processes to explain distribution of populations at a local scale.
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