3/18/2009

The littlest birds!

Good days go by, it has been beautiful out. The bikes I've kept in storage all winter are out in the living room, getting more and more use. I recently have been riding a lot of bicycles, my friend Matt said he likes to lean over the handlebars so that he can't see any parts of the bike and imagine he is soaring over the ground. He and I soared last night, it was the end of a long day punctuated by both successes and confusion, and some funny parts, too.

Every other week this semester I give presentations on some concepts in evolutionary genetics. Specifically, I learn how body-parts evolve, how species come up with new appendages, new ways to solve problems encountered in their environment. So the evolution of the creation of new traits, if you will. I think its a really great new field, people are making a lot of discoveries because we have so much more information about animals' genomes and even about individual genes. How genes interact, where they interact, the confusing webs of activation, deactivation.

I thought of an analogy: imagine a huge switch board with many light bulbs at the edges, and there are so many switches, turning the switches on and off in a variety of combinations results in maybe one light turning on somewhere, or turning off, or dimming. Now in trying to create an arm or a leg or an antenna, the precise combination of switches (genes) have to be turned on in the right way at the right time... and that's just one step. People are beginning to see these patterns, to learn how genes act on each other. I presented yesterday about developmental drift, in which two species (or even two populations) might have similar traits and similar looking body parts, but the way they arrive at the creation of that perfect adaptation, they may actually go through two completely different genetic processes. So a homologous/analogous instrument actually happens in a new way and only now with studying the individual genes in these pathways are we seeing that things happen very differently than we thought. Its like taking two different routes to arrive at the same place, or using different switches to get the same light bulb result.

I am going on a birding trip this weekend, and I hope I think about some of this stuff. Expect photos! I leave you to think about these now:


The analogies of evolution are very appropriate sometimes.

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