Friday, January 22, 2010

Building the Bat Family Tree

Last night we had another great Born to Do Science event here at the Stillwater Public Library.

I kicked things off with a new song called "Bat Man." (I'll get these songs posted one day, really, honest!)

Dr. Ron Van Den Bussche then guided us on how to study the tree of life. We learned that species that look alike may not actually be closely related. And visa versa: species that look very different can be closely related.

How do we know? By studying genes. The more closely related two species are, the more genes they have in common.

The physical characteristics of species (morphology) can be misleading. Studying genes can lead us to new conclusions about who's closely related to who. Then we can go back and look at morphology more closely to verify the new information.

That gives us multiple lines of evidence, or two different ways of knowing. When they agree with one another, we can feel more confident we've got it right. When they disagree, we need to do more research.

We also learned many cool things about bats. There are 1200 different kinds; the smallest is the size of a thumb; the largest has a wingspan as wide as a basketball player is tall.

At the end of the presentation, we looked at bat specimens. All the small brown bats in the photos below are members of the bat family that Dr. Van Den Bussche is trying to sort out. Each sample represents a different species.

Notice that there isn't much to go on as far as morphology is concerned! That's one reason this family of bats is the last to be organized. Dr. Van Den Bussche is the only one working on them. He's using DNA to sort them all out.

Next month, February 18 - wind energy! See you then!

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