\ Visualizing Evolution: Cladograms: History, Diversity, and/or Geography

Thursday, December 11, 2008

Cladograms: History, Diversity, and/or Geography

Cladograms at their most basic level give information on which species or groups of species are most closely related--in other words, which have the most recent common ancestor. Cladograms can also give information on evolutionary history (how long ago the branching events occurred) and diversity (which branches became most 'successful').

Here is one from Nature that does both of these things:
What's more unusual is to have a phylogeny that also includes geographical information. I came across this one yesterday on the blog Living the Scientific Life:
Read the above linked blog for a summary of the article. I'm just here to show you the cladogram! This one combines the traditional phylogeny with history (in this case by color-coding the nodes and including a key) and geography, by ending each branch at the location of the modern species. In this case it seems to have worked out cleanly, with only one case of crossed lines. But, I'd imagine other attempts, perhaps with non island-dwelling species, would be much messier.

What I want to find now is a cladogram that manages to combine all three: evolutionary history, diversity, and geography, in one image. Perhaps in some cases it would even be possible to place the nodes on the geographical location where the common ancestor is thought to have lived!

No comments: