|
1-6 of 6 messages
|
Page 1 of 1
|
|
why so fat?
|
Reply
|
|
by asud on April 23, 2010
|
Mail this to a friend!
|
i've been thinking about bitis - gaboons mostly - for the last year or so and it's only now occurred to me to ask: what might be the evolutionary pressures (and advantages) to being so, um, fat?
i've read a bit about adaptive constipation, their possibly using fecoliths as strike ballast. and there's puffing out the ribs to appear bigger, right? any other reasons anyone can think of? do they have unusually large fat stores? are the organs outsized? might there be any advantages to a strictly terrestrial, tropical snake in being so thick (i'm thinking heat retention on a cool, dark forest floor)?
on a side note, if anyone lives within a day's drive of nyc and owns a particularly large gaboon and wouldn't mind letting me have a look, well, i'd be eternally grateful. (the ones at both the bronx and staten island zoo are smaller and it'd be a thrill to see a big one up close...) thanks, adam
|
| |
|
RE: why so fat?
|
Reply
|
|
by Crotalusssp on April 23, 2010
|
Mail this to a friend!
|
|
Another hypothesis to kick around would the fact that larger head and girth would allow for a wider variety of prey source size. The snake would be able to immediately feed upon larger items.
|
| |
|
RE: why so fat?
|
Reply
|
|
by asud on April 23, 2010
|
Mail this to a friend!
|
good point. still, i wonder: i feel like a lot of the boids and maybe even temperate climate snakes go longer between meals than your average gaboon. any other factors that could contribute to what seems to me an extreme body type?
come to think of it, is there any snake that's even more sluggy than the gaboon - that, overfed examples notwithstanding, has even a comparable girth to length ratio? i can't think of one...
|
| |
|
RE: why so fat?
|
Reply
|
|
by MikeB on April 23, 2010
|
Mail this to a friend!
|
|
The blood pythons have a similar body type -- not that long and very heavy girth. As I understand it gaboons (and probably the blood pythons as well) are mostly ambush predators that just lie there and wait for something to come by. Modt rattlesnakes are too . . . hence their feeding frequency would be somewhat less often than, say, a rat snake, which is alwals moving and tracking possible prey. I would therefore guess that wide girth equals large prey capacity equals a survival advantage that helps those who can get down, say, a small pig or mid-sized mammal live and reproduce more than a slimmer snake confined to rodents.
|
| |
|
RE: why so fat?
|
Reply
|
|
by FSB on April 26, 2010
|
Mail this to a friend!
|
|
I think temperature regulation could well be a factor. Heavy-bodied snakes such as gaboons tend to do better at temperatures on the lower end of the normal herp gradient, say from 76-80F. While their girth does make it possible for them to eat larger prey items, it also helps prevent the snake from becoming easy prey for a variety of other predators, including birds and other snakes. A big fat gaboon would be a far more intimidating meal than a slender colubrid.
|
| |
|
RE: why so fat?
|
Reply
|
|
by earthguy on April 26, 2010
|
Mail this to a friend!
|
|
I'm with Frederick on this one...temperature regulation could be a powerful selective pressure for poikilotherms...especially ambush predators that spend a great deal of time out of direct sunlight. Thicker bodies lead to a lower surface area:volume ratio. Of course Charles' point about wider prey selection is at least as valid. Natural selection is NOT one dimensional, so both (and probably more not mentioned) probably play a role.
|
| |
|
Email Subscription
You are not subscribed to this topic.
Subscribe!
My Subscriptions
Subscriptions Help
Check our help page for help using
, or send questions, comments, or suggestions to the
Manager.
|
