T exoskeleton...hard or elastic?

[kosh]

i thought that the exoskeleton was supposed to be hard because they dont have an internal skeleton??
just curious because it seems like no matter how much you feed a T/sling they can always stretch out fatter!?!?!
so is it hard or elastic or what?:?

 

[Code Monkey]

Are you talking about the abdomen or the ceph and legs? The ceph and legs are fixed in size although there is some minor wiggle room depending on internal pressure. The abdomen is just soft skin and can stretch and stretch as you have seen.

 

[kosh]

i was talking about abdomen......
why would the legs and other part be hard and not the abdomen.....isnt the abdomen one of the weakest places (internal organs and such).......seems like it would be easy for another T or predator to just munch or crunch the abdomen........

 

[Code Monkey]

Two thoughts come to mind.
One, having such a flexible storage container must give them quite a survival advantage. When times are rich, they can feed and feed far beyond what they will need in the near future. And, when times are lean, the abdomen shrinks down and they're not wasting unnecessary engery lugging around a hardened but empty storage case.
Second, ever see the pictues of a threatened T? They're not presenting the abdomen, they're presenting the business end of things.

A secondary pondering - old world species actually have much smaller abdomens on average than new worlders, they also have no urticating hairs. Perhaps the urticating hairs on the abdomen serve an additional function of making it a less desireable target so they can afford to get fatter than their Asian and African cousins who must remain lean and mean, presenting a smaller vulnerable target.

A last pondering, ancient ancestors of modern spiders did have a segmented, somewhat armored abdomen and they lost it in favor of these balloon ones.