Fossil Bone, Fish Vs. Reptile, Examples?

[Tony Eaton]

This may have already been posted before, but curious if anyone has handy some magnified images of fish bone versus reptile bone?

As I've read many times on the forum the difference of bone texture is a fairly clear cut diagnostic indicator of fish or reptile. I have some clear cut fish bones, and clear cut reptile bones, and as many more that are vague. Just wondering if anyone has some example pics, weblinks, or even more detailed explanation of what to look for.

Thanks!

[siteseer]

This may have already been posted before, but curious if anyone has handy some magnified images of fish bone versus reptile bone?

As I've read many times on the forum the difference of bone texture is a fairly clear cut diagnostic indicator of fish or reptile. I have some clear cut fish bones, and clear cut reptile bones, and as many more that are vague. Just wondering if anyone has some example pics, weblinks, or even more detailed explanation of what to look for.

Thanks!

Part of it depends on the preservation of the site but fish bone is generally more flaky and brittle. I know what you mean because one of the areas I've collected at has fish stuff and occasional sea turtle bones. I think I've separated it correctly but there are a couple of partial specimens that aren't clearly anything. You should post some photos of your vague specimens.

[tracer]

there are a lot of pictures of bone on this forum in various places. there are some decent pictures of fish bone and marine reptile bone on the oceans of kansas site.

but basically, the difference isn't so much between fish and reptile bone, as it is fish just being different from most other bone from most critters. and it isn't just the texture or surface look of the bone. fish bone is laminated or even sometimes fibrous in appearance, as if it was laid down in sheets or fibers and pressed together. the bones tend to be flatter and seem like they have more tensile strength, like they're designed to be thin and strong while flexing as opposed to being monolithic, weight-bearing structures. and they mineralize a bit differently. it seems like they more often have a reddish cast to them compared to the dark-brown or black color of other bones.

to me, fishbone looks different enough that even if you find a broken piece of it that doesn't have any of the normal features, you can still tell it's fishbone.

[Tony Eaton]

Thanks Siteseer and Tracer. Good explanations. I've read a few posts citing "under a microscope" which made me wonder just how obvious the difference is at that level. I need to get around to posting some of the old bone material in the ID section. Most of it was found before this forum existed and after I wore thin the patience of the experts I had access to

[siteseer]

there are a lot of pictures of bone on this forum in various places. there are some decent pictures of fish bone and marine reptile bone on the oceans of kansas site. but basically, the difference isn't so much between fish and reptile bone, as it is fish just being different from most other bone from most critters. and it isn't just the texture or surface look of the bone. fish bone is laminated or even sometimes fibrous in appearance, as if it was laid down in sheets or fibers and pressed together. the bones tend to be flatter and seem like they have more tensile strength, like they're designed to be thin and strong while flexing as opposed to being monolithic, weight-bearing structures. and they mineralize a bit differently. it seems like they more often have a reddish cast to them compared to the dark-brown or black color of other bones.

to me, fishbone looks different enough that even if you find a broken piece of it that doesn't have any of the normal features, you can still tell it's fishbone.

Yes, that is a better description but fish bone has that laminated look only where it is well-preserved. In the Sharktooth Hill Bonebed, there are sites where you get nice shiny chocolate-brown bone of mammals, birds, sea turtles, and fishes (similar to layers of the Niobrara), but at other STH sites the bone is dull, white/off-white and less-mineralized. That is where it does look and feel more fibrous. Of course, when dustinguishing fish from reptile, a basic knowledge of comparative anatomy solves a lot of mysteries. If you can recognize a partial hypural fan or a piece of plastron, you recognize the shape of the bone being more important than the look. It's when you are sorting out a day's finds down to the fragments, that you ask yourself if you can still be sure of even a basic ID.