Posted by:
chris_harper2
at Sun Sep 12 21:56:58 2004 [ Email Message ] [ Show All Posts by chris_harper2 ]
Convergent evolution, or convergence, requires the traits in question to be analagous, not homologous in the two different groups.
Now what trait are we talking about here? The skin color or the stripe through the eye?
Certainly the skin and mostly likely the genes controlling coloration are homologous structures in any type of snake. In other words, the "blue skin" genes in distanly related groups of snakes are likely homologues.
However, there might be important regulatory genes controlling the distribution, pattern, etc. of different colors in different snakes that are analogues.
I think it gets a bit tricky in these situations to uncouple convergent evolution from parallel evolution. In fact I think determining convergence from parallelism get's more difficult the more closely two species are related and the less discreet the traits in question are.
This example (whichever it is) is not as straightforward as comparing bat wings to mosquito wings (an example of convergent evolution).
For the record, I also only have a BS in Biology.
-----
1.1 Gonyosoma oxycephala - (Silver/Yellow)
3.4 Gonyosoma oxycephala - (Green)
2.1 Gonyosoma janseni - (Black)
[ Hide Replies ]
|
Convergent Evolution - chris_harper2, Sun Sep 12 21:56:58 2004