Thursday, September 04, 2008

A New Shiner Brain Project

Jennifer (and Alexandra?) has agreed to start work on a project to characterize brain size in telescope shiners, Notropis telescopus. We have lots of telescopes left over from last year's project, each in a tube of buffered formaldehyde sexed and measured. The interesting thing about this is that we can compare them to scarlet shiners. Scarlets are sexually dimorphic, with larger, colorful males. Telescopes are not sexually dimorphic, and I have trouble telling adult males from females. We've found pronounced differences in scarlet shiner brains between males and females. So, the question is, are similar differences present in telescopes? The two species are found in the same creeks, such as Hurricane Creek at the Walls of Jericho, so both should be well adapted to living in clear, flowing waters. But they probably have different reproductive ecologies (I realize I'm not sure exactly how telescopes spawn; I'd bet it doesn't involve alpha males defending territories, unlike scarlets.)

We're going to use the telescope shiners from May and June, what we found to be the peak of the spawning season, to compare them to scarlet shiners that we examined from the peak of their spawning season. With no pronounced sexual dimorphism, are male brains not very much larger than females, or maybe even females have bigger brains? I have no idea, which of course makes for fun research.

0 Comments:

Post a Comment

<< Home