Mini Mosasaur collection

A few observations:

The larger mosasaur vertebra in the upper left is a somewhat eroded specimen.  Assigning "predation marks" is very speculative.  

The lump in the middle of photo may or may not be a coprolite.  From this view it's not identifiable.  To say that it is a mosasaur coprolite is an extremely wild guess on someone's part.  I doubt that it was found in immediate, associated context with any mosasaur skeleton (if it was, then it would still have been kept with such a rare find)...in my opinion.  Lots of things pooped in the ocean; most results did not preserve.  Of those that did, I don't think there are diagnostic features that have been proven to be mosasaur poop as opposed to plesiosaur or other marine vertebrate.

I assume the label next to the Moroccan mosasaur tooth goes with the light colored vertebra at the top...it's hard to tell if that is a mosasaur bone.  

Remember, good labeling comes from good research on your own.  Everyone makes errors in ID...assuming what someone told you was the ID without checking is just hoping they were right.   

21 hours ago, JohnJ said:

A few observations:

 

The larger mosasaur vertebra in the upper left is a somewhat eroded specimen.  Assigning "predation marks" is very speculative.  

 

The lump in the middle of photo may or may not be a coprolite.  From this view it's not identifiable.  To say that it is a mosasaur coprolite is an extremely wild guess on someone's part.  I doubt that it was found in immediate, associated context with any mosasaur skeleton (if it was, then it would still have been kept with such a rare find)...in my opinion.  Lots of things pooped in the ocean; most results did not preserve.  Of those that did, I don't think there are diagnostic features that have been proven to be mosasaur poop as opposed to plesiosaur or other marine vertebrate.

 

I assume the label next to the Moroccan mosasaur tooth goes with the light colored vertebra at the top...it's hard to tell if that is a mosasaur bone.  

 

Remember, good labeling comes from good research on your own.  Everyone makes errors in ID...assuming what someone told you was the ID without checking is just hoping they were right.   

The round indent on the vertebrae is actually pretty clear in person, it's just not as good from this picture.

I'm no expert in corprolites, I don't even like them. It was just sent a bonus sent with the other stuff I bought from them. this is the same kinda thing we were talking about in that other thread. Even though it might fit other things also, if it does perfectly fit what its claimed as, and i have no reason whatsoever to doubt the claim, I just think it's kind of silly to just automatically reject every claims u can't personally verify. If it was something major and significant, I would definitely look at it differently, such as the Edaphosaurus fossil with the bite mark claimed, but unproven, to be by a dimetrodon. I mean, the person who ID'd the corprolite, or any fossil, may very well have know exactly what they were looking at, and by just doubting the claim, I just ruined the fossil in a way. It may have been a definite mosasaur fossil, and by me just stating something like "claimed to be", or anything uncertain, I suddenly destroy all credibility of the fossil, and turn it from a fossil to just something unidentified. From there anyone can change the fossils ID to whatever they believe it to be. I think there's just as much damage to fossils by erasing their possible definitive identity just because I personally can't verify it myself, and just assuming that someone didn't know what they were talking about. If there's any reason to doubt the claim, that's a totally different story, but if it fits the claim perfectly, I feel just as uncomfortable throwing out a perfect ID that is as likely to be correct than incorrect, than I do if I were to just blindly accept claims without at least looking into it myself. Again also, if it's something significant, unlike a little turd, I'd absolutely look at it very differently. I don't know, i know you're not wrong, it's really a frustrating sort of lose-lose situation, and a difficult decision, and shouldn't just be an automatic thumbs down without any actual reason. I'm very sorry, I really don't mean to be a huge pain. You may be right, and I don't want to be wrong, but I just feel differently about how to handle it:(

That being said, again, I don't know about  corprolites, so for all I know this one DOESNT fit perfectly with the claim! 

So there really isn't any realistic way to differentiate corprolites, like that? I guess that IS a good reason to doubt the claim! 

also, the small vertebrae does seem a little odd looking for a mosasaur. I'm thinking now it may be a shark vert. In the meantime I will change THAT one.

What is that large vertebra called? Is it a single one, or two, or so, per skeleton, or are there multiple of that shape along the spine?

Look at this way...by assigning an ID, you are saying to the world what YOU think something is.  If you haven't invested a reasonable effort to support the specific comments you make about a particular specimen, then you risk spreading misinformation.  Specific comments made about marks on fossil or saying this or that rock is fossil poop from this kind of animal should be supported by a lot more than hearsay.  Not doing so, leads to bogus IDs that "destroy the credibility" of the person willing to state, "This is 'X'!  Believe me!"  It's up to each person to decide; but since we are a science-based forum, fantastic claims will face polite challenges to provide evidence.   

5 minutes ago, JohnJ said:

we are a science-based forum, fantastic claims will face polite challenges to provide evidence.

^ This!

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