Some hominid evolution items 19 Aug 2009 Two items worth reading: Mailund notes that the 2006 claim of complex speciation, involving gene exchange for some time after the chimp and hominid lineages split, has been argued against on the grounds that high rates of sperm production in humans and chimps could generate the effect. Pleiotropy discusses the Hobbit’s phylogeny, noting that the cladistics won’t determine whether it was a distinct species, because just putting the specimens into the data matrix presumes that they are: The fishy part is that in order to construct cladograms like the ones above, the authors assumed that H. floresiensis and H. sapiens are different species. Once that is done, no other conclusion can be reached. Evolution Species and systematics Species concept Systematics
Evolution Alien life in Phoenix 10 Jun 2009 I find Paul Davies, the physicist who gets quoted on everything, really annoying sometimes. This is one of those times. Davies appropriates another’s ideas (Carol Cleland’s), arguing that we should look for a “second kind of life” on earth. Then he appropriates yet another’s work (Philippa Uwin’s work on nanobes),… Read More
Ecology and Biodiversity Ecological speciation 30 Sep 201118 Sep 2017 A new paper in the Journal of Evolutionary Biology (link below) assesses the possibility of speciation by ecological differentiation in conjunction with geographical isolation. The interesting thing here is that it takes two views previously considered as antagonists and combines them into a single model. “Standard” views of speciation assume… Read More
Creationism and Intelligent Design The tautology problem 20 Aug 2009 A long time ago I wrote a not particularly good piece on the tautology problem: that natural selection is merely circular definition. I was just out of being an undergraduate when it was published, so it was at best an undergraduate piece. I have been unsatisfied with it ever since…. Read More