Speciation
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Category archives for Speciation
All those types of speciation
Posted by RPM on December 16, 2008 Over at Wilkins’ cabana, there’s a post (Some new work on speciation and species) on a paper by Nitin Phadnis and Allen Orr (doi:10.1126/science.1163934). Phadnis and Orr isolated a gene responsible for both reproductive isolation and sex-ratio distortion between two populations of Drosophila pseudoobscura. Wilkins doesn’t like speciation genes, and he’s rails on the concept…
Evidence that Men Think With Their Junk
Posted by RPM on April 8, 2008 Us dudes are always accused of thinking with our dicks. Perhaps it’s because the genes expressed in our brains are similar to those expressed in our ‘nads: Among the 17 tissues, the highest similarity in gene expression patterns was between human brain and testis, based on DDD and clustering analysis. Genes contributing to the similarity…
Cleaning Up the Browser Window
Posted by RPM on July 8, 2007 I’ve got far too many tabs open in my browser window, and I gotta blog them ASAP so that I can clean up the ol’ computer. Here are a few things I’ve been meaning to blog, in list form: Nature Genetics has published an issue devoted to structural variation in genomes. There appears to be…
Attack of the Hybrids
Posted by RPM on May 25, 2007 For some reason, I have been collecting links to articles involving hybridization. That, on its own, would call for a massive link dump, but a recent news item makes for a nice contrast. First, the hybrids: Where better to start than this review of hybrid speciation — a topic I’ve discussed previously. The take home…
Genetics of Speciation
Posted by RPM on April 27, 2007 The most recent issue of the Journal of Heredity contains a bunch of articles from a symposium on the “Genetics of Speciation” organized by Loren Rieseberg. Included in the collection is an article by Allen Orr and two of his students on speciation in Drosophila, which discusses mapping speciation genes, the role of meiotic drive…
Phylogeny Friday – 27 April 2007
Posted by RPM on April 27, 2007 This week’s phylogeny comes from this paper on molecular dating of speciation events. I won’t be addressing molecular dating per se, but I will be dealing with what molecular clocks tell us. Like, do they actually reveal the speciation time of a pair of species?
A Blow Against Hybrid Speciation?
Posted by RPM on April 5, 2007 A recent flurry of papers (reviewed here) have presented evidence for homoploid hybrid speciation in insects — one in Rhagoletis (a fruit fly) and two in butterflies (one in Heliconius and one in Lycaeides). The Rhagoletis paper showed that a hybrid species formed from two other species — one that feeds on snowberries and one…
Speciation, Natural Selection, and Karyotypes
Posted by RPM on February 5, 2007 I’ve been chatting up Wilkins about the role of natural selection in speciation (and when I say “speciation” I mean “reproductive isolation”). Wilkins listed a few cases where speciation would occur independently of natural selection. Amongst the mechanisms in Wilkins’s list was speciation via karyotypic changes (polyploidy, inversions, fusions or fissions). I cried shenanigans, and…
Of Genes and Species
Posted by RPM on January 30, 2007 I straddle the line between being a population biologist and a molecular geneticist. That’s a self-congratulatory way of saying that I am an expert in neither field. But existing in the state I do allows me to observe commonalities shared by both. For example, both fields have terminology (or what the uninitiated would call jargon)…
Wilkins Replies
Posted by RPM on January 24, 2007 Wilkins has replied to my post on species concepts. The gist: there are a bunch of species concepts, many of which are pretty darn good. My reply: that’s awesome as long as they guide future research. The BSC provides a framework for studying reproductive isolation. Ecological species concepts are useful when studying adaptation to niches.…