Reptile & Amphibian Forums

from the pics that i have seen it looks like bcc have a bigger head to body ration then bci... is this true or could it be due to feeding?

A lot of things combine to effect the size and (to a lesser extent) shape of a Boa's head.

Subspecies, locality, age, growth rate, caging, even injury all have an impact on how big, how round or square the head appears. Contrary to what many may popularly believe I do not think prey-size has anything to do with relative head size. In Boas of any locality or subspecies the dominant factors are age and rate of growth.

To answer your specific question it is without doubt true that examples of most BCC populations will have somewhat larger and more angular (appearing ) heads than BCI would.. assuming that both animals were caged and fed the same.

Hope that helps!
-----
Gus
A. Rentfro
RioBravoReptiles.com

"Quality is not an accident. Perfectly healthy animals are a minimum requirement.. everything else is just salesmanship" gus

I must disagree with Gus. I think it is clear that there is a fair amount of phenotypic plasticity, especially in the musculo-skeletel systems associated with feeding in squamates. Sure, much of the variation is heritiable, but I'd be shocked if--given equivilant caloric intakes--snakes fed singnificantly larger food items did not develop larger heads, or at least increased cranial kinesis. As an aside, this is something our lab is working on right now in wild populations of water snakes in Florida.

cheers,
Gabriel

.. that is an admirable display of vocabulary! Still, you claim only to be expecting to see your theory proven in an upcoming or ongoing investigation into growth rates of watersnakes.. Such pre-expectations can hardly contribute to unbiased laboratory models! Still, we trust your methodicity.

To continue, I was commenting largely from experience of the effects of age and growth on morphology in the Boa sp.. I'm going to have to yield to your work with the watersnakes..

BTW.. how will you determine that your subject snakes are being fed the same amounts of proteins, lipids, and so on while you are testing their cranial kinesiology with different-sized prey items? Have you concocted an homogenous product that you form into ersatz-fish of different guage(s)?

I know that last question seems a little sarcastic but I really would like to know more about the experiment.

Thanks!
-----
Gus
A. Rentfro
RioBravoReptiles.com

"Quality is not an accident. Perfectly healthy animals are a minimum requirement.. everything else is just salesmanship" gus

Look at Scot Bobak's (sp?) research in Craig Guyer's lab at Auburn. He is actually looking at differences in insular versus mainland populations in populations of Bci and Bcc including many of the popular forms seen in the trade (crawl caye, hog island etc...). Just go to auburn.edu and search for Craig's homepage, it should have all the links you need.

cheers,
gabriel