Combining phylogeographic data from mitochondrial DNA (mtDNA) of Nearctic and Palearctic freshwater and anadromous fishes, we used a comparative approach to assess the influence of historical events on evolutionary patterns and processes in regional fish faunas. Specifically, we (i) determined whether regional faunas differentially affected by Pleistocene glaciations show predictable differences in phylogeographic patterns; (ii) evaluated how processes of divergence and speciation have been influenced by such differential responses; and (iii) assessed the general contribution of phylogeographic studies to conservation issues. Comparisons among case studies revealed fundamental differences in phylogeographic patterns among regional faunas. Tree topologies were typically deeper for species from nonglaciated regions compared to northern species, whereas species with partially glaciated ranges were intermediate in their characteristics. Phylogeographic patterns were strikingly similar among southern species, whereas species in glaciated areas showed reduced concordance. The extent and locations of secondary contact among mtDNA lineages varied greatly among northern species, resulting in reduced intraspecific concordance of genetic markers for some northern species. Regression analysis of phylogeographic data for 42 species revealed significant latitudinal shifts in intraspecific genetic diversity. Both relative nucleotide diversity and estimates of evolutionary effective population size showed significant breakpoints matching the median latitude for the southern limit of the Pleistocene glaciations. Similarly, analysis of clade depth of phylogenetically distinct lineages vs. area occupied showed that evolutionary dispersal rates of species from glaciated and nonglaciated regions differed by two orders of magnitude. A negative relationship was also found between sequence divergence among sister species as a function of their median distributional latitude, indicating that recent bursts of speciation events have occurred in deglaciated habitats. Phylogeographic evidence for parallel evolution of sympatric northern species pairs in postglacial times suggested that differentiation of cospecific morphotypes may be driven by ecological release. Altogether, these results demonstrate that comparative phylogeography can be used to evaluate not only phylogeographic patterns but also evolutionary processes. As well as having significant implications for conservation programs, this approach enables new avenues of research for examining the regional, historical, and ecological factors involved in shaping intraspecific genetic diversity.
Molecular Ecology – Wiley
Published: Feb 1, 1998
Keywords: ; ; ; ; ;
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
Get unlimited, online access to over 18 million full-text articles from more than 15,000 scientific journals.
Read from thousands of the leading scholarly journals from SpringerNature, Wiley-Blackwell, Oxford University Press and more.
All the latest content is available, no embargo periods.
“Hi guys, I cannot tell you how much I love this resource. Incredible. I really believe you've hit the nail on the head with this site in regards to solving the research-purchase issue.”Daniel C.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud
“I must say, @deepdyve is a fabulous solution to the independent researcher's problem of #access to #information.”@deepthiw
“My last article couldn't be possible without the platform @deepdyve that makes journal papers cheaper.”@JoseServera