Question About Bones

[texaswoodie]

Out west they have dino bones that are agatized and look great cut and polished. The cells are very distinct and have a great pattern. I've noticed that the Mosasaur bones we find here have very small cells in a tight pattern and do not look all that good when cut. I mentioned this to a friend who told me he hunted whale bone while in CA and the bone looked very similar to the Mosasaur bone.

My question is

Do all marine animals have similar bone structure and does it always differ from land animals?

[Boesse]

That's largely controlled by the density of the bone. For example, whales have extremely porous bone that looks nice when tumbled or polished. Sea cows, on the other hand, have extremely dense bone (that also looks pretty nice when tumbled). These are different adaptations for maintaining bouyancy, and it all depends on the physiology and bouyancy of the ancestors of these critters.

Bobby

[tracer]

i have noted a great degree of different between the "cell structure" of cancellous bone even between different bones in the same type of animals. although there are multiple functions of cancellous bone, i believe a significant one for most animals is providing structural support with less weight than cortical bone. so then, because all animals are not in need of the same amount of bone strength, and every bone in them doesn't need to be equally strong, the cancellous "cells" differ in size. mixed in with this concept would be any need for buoyancy regulation, and all the other functions, like blood cell production, etc. reading up on what all "bone marrow" does is kind of amazing.

anyway, back to your original question. other than cell size, the reason the mosasaur material doesn't polish as well as the western agatized dino bone is because it isn't mineralized as perfectly with agate. no matter how much it's polished, examining it with a loupe will reveal micro-porosity. that is a problem with a lot of stone from a lot of places, and is why nice agate is highly prized, regardless of whether it is pseudomorphing anything originally organic.

the cancellous part of whale bone to me looks pretty "normal" to me compared to a lot of mammal bone. manatee rib bone is almost solid with little internal structure visible. fish bones look a lot different externally to me in most every way to me from land mammal bones, but i haven't looked inside a bunch of fish bones.

i think the question was a complex one, but an interesting one. the more i study certain things, the less i feel i actually know about them, because my awareness of their complexity keeps increasing.

[texaswoodie]

As far as polishing, I've found a lot of silicified bone here in NE Tx that will polish. My question is more about the bone structure.

It seems to me (I'm a rank amatuer) that marine animals would have more cancellous bone than the land animals, which means the marine bone should have a better cell pattern since it is more porus. It seems the opposite is true.

I haven't cut a lot of marine bone so I'm going by my very limited experience.

[tracer]

from a purely structural point of view, cancellous bone seems to make possible making a stiffer, wider, stronger bone of less weight than otherwise necessary, like the "honeycomb" structures humans have been fabricating for a few decades now to add lightweight strength to structures. which normally would seem less necessary under water. but the other side of that is pressure equalization in diving/ascending situation. gasses have to move in and out of voids more than dense filled areas.

but again, i feel pretty "out there" in attempting to grasp the true nature of this issue, in that i suspect it is very, very complex with numerous variables coming into play. but it is really interesting.

[tracer]

pages 124, and then 125...

link

so many good books to buy out there...

[texaswoodie]

Aha! Once I was blind, but now I see. Thanks Tracer, makes perfect sense to me. And as you said, it's a complex question, but I think you may have nailed it.