For people who are interested in these things, there is a fascinating article in the Washington Post about the genetic code of the platypus. Scientists just finished mapping the odd animal’s DNA and not too surprisingly, it’s odd. What is particularly useful about this is that scientists have been able to map segments of the platypus’ genetic code which are similar to those found in birds, mammals and reptiles. Over the ages, and at crucial times in the evolution of life, there were probably many transitional animals bearing the imprint of multiple orders of animals. We are just lucky to have this one living example to give us a peak at how it worked itself out.
One of the things which I also found interesting about the article is that it repeatedly refers to evolution in anthropomorfic terms. Evolution is referred to as trying things out, working out how to do something, deciding, etc. One of the things which people often do not realize is that evolution is not nearly as random or unintelligent as it is sometimes portrayed. For example, we know that there are genetic sequences which can cause similar but different outcomes in different animals, depending on how it is tweaked. For example, the platypus makes milk which is a variation on a milky substance which its ancestors made to keep their leathery eggs from drying out. In other animals, we see that light sensing cells can evolve into organs which detect electrical currents. So rather than being a completely random process, evolution seems to have given life genetic sequences which act something like one of those tool kits with the different bits and sockets that can be changed out. The basic genetic sequence is about the same, but can be easily modified to fit different needs. This would accelerate the process of evolution as slight mutations in these genetic sequences are far more likely to be useful than completely random mutations spread over the entire genetic sequence.
Anyhow, there’s your science lesson for the day. Hopefully I didn’t mangle it too badly. 🙂