Thursday, March 11, 2010

Mystery Pleistocene bones

Hey folks, I've been rather busy preparing for spring break (which I leave for in about 30ish hours), and I've actually gotten quite a bit accomplished - I finished preparing the whale cranium from the aforementioned post (there will be more follow up posts to that soon), and as of this afternoon, finished the second plaster/fiberglass cradle for the skull, which I will eventually be able to sink bolts through to keep the two halves together. Tommorrow I'll be attaching foam to the inside of the cradles, and then lugging the whole monstrosity to my (rather small) car. However, as this thing now weighs around 100 lbs or so, it is still only 1/3 of its original weight, so my car can do it.

Other than that, I submitted a manuscript this week (late monday night), about bite marks on some bones from the Purisima Formation; you'll hear more about it later on down the line.

Mystery marine fossils from the Pleistocene.

Anyway, as part of my mental preparation for spring break and looking at marine Pleistocene "rocks", here are some Middle Pleistocene fossils from a marine unit in California. I haven't been able to ID them, but they were originally ID'd by the collector as sea turtle claws. I'm naturally skeptical of that, but I'd like to see what you folks think, or if anyone can come up with something better (or, validate that ID).


Brian Lee Beatty said...

Hi Bobby,
Those look like what are known as "Tilly bones", which are unusual thickenings of the vertebrae and/or spines common to some teleost fishes. The oldest ones I know of are from Miocene deposits of FL, though I wouldn't be surprised if they are found in older fishes too. No one knows what causes it, but some fishes have it more than others. A nice study of it in modern teleosts was done in 1995, by Smith-Vaniz et al.

J. Velez-Juarbe said...

Hi Robert,

You should indeed be skeptical about their original id, marine turtle fingerbones are very slim and elongated as well as flattened (same as with other marine critters). Brian's id of Tilly bones is more likely.

Alton Dooley said...

We have zillions of these from Carmel Church (well, OK, not zillions, but certainly hundreds). There seems to be a variety of morphologies, but I don't know the significance of that.

Robert Boessenecker said...

Oddly enough, I visited the locality over spring break, and found one that was very well preserved, and it had that sort of 'flaky' texture typical of fish bones.

I never seriously thought these had anything to do with sea turtles, especially given the Pleistocene age (and occurrence in the Pacific NW).

RE: tilly bones, I'm basically SOL, because I hate bony fish, with a passion. So - someone who wants to work on the bony fish of this deposit can do it. I want some good, clean marine mammal material