Jump to content

ThePhysicist

Recommended Posts

Hey y'all. I got some peace river gravel and found some small shark teeth in it. There's a few interesting ones that I can't decide what they are. They might not be identifiable, but I'm just curious if they are. Thanks!

IMG_1527.jpg

"Argumentation cannot suffice for the discovery of new work, since the subtlety of Nature is greater many times than the subtlety of argument." - Carl Sagan

"I was born not knowing and have had only a little time to change that here and there." - Richard Feynman

 

Collections: Hell Creek Microsite | Hell Creek/Lance | Dinosaurs | Sharks | SquamatesPost Oak Creek | North Sulphur RiverLee Creek | Aguja | Permian | Devonian | Triassic | Harding Sandstone

Instagram: @thephysicist_tff

Link to comment
Share on other sites

This looks like a fairly-typical load of teeth that shows up in my sifter on any given trip to the Peace. So, your gravel material is a pretty good representation of the locality. I'm not a tooth expert and land mammals are more my thing. But, I do keep all the nicer teeth I find and keep my eyes peeled for the bigger ones like megs and large hemis, makos, or hastalis types. I use the chart below as a cheat sheet sometimes. I always get the smaller and more common species mixed up. There are so many types of teeth depending on their location in the overall dentition, and my struggling brain can't keep up and a lot of them just look the same. Hopefully this chart helps and somebody else chimes in with more expertise.

 

shark-teeth-id-chart.jpg

  • I found this Informative 4
Link to comment
Share on other sites

Thank you @Bone Daddy.  That's a helpful visual aid.  Do you (or anyone else - @digit, perhaps) know if any similar guide exists for the micro teeth found in the Peace River gravels?

Link to comment
Share on other sites

44 minutes ago, grandpa said:

Thank you @Bone Daddy.  That's a helpful visual aid.  Do you (or anyone else - @digit, perhaps) know if any similar guide exists for the micro teeth found in the Peace River gravels?

It's not perfect. It has a spelling error in it (threser versus thresher), but it covers the most common ones, except for the big chub, which I rarely see those in the river itself and those seem to be more common on dry land sites (at least in my experience). I found that on a web image search a while back and I don't recall who made it or I would give them credit.

 

I have a bunch of those micro-teeth as well (mm scale size, give or take) and I am curious about them as well. I need to snap some photos of them, but that tiny stuff can be tricky for a subpar photographer like myself.

 

Link to comment
Share on other sites

3 hours ago, grandpa said:

Do you (or anyone else - @digit, perhaps) know if any similar guide exists for the micro teeth found in the Peace River gravels?

Don't know of one but it would be great to have--though so few folks (at large) pay much attention to micro fossils so it would not be a best seller. ;) I think we have a higher per-capita interest in tiny micro-fossils here on the forum than is present in fossil hunters in general. You can find tiny versions of all of the larger species (with the possible exception of megs, makos, and whites) represented in the micro-matrix. Tiny tiger, anyone?

 

P3100890.jpg

 

 

Additionally, you'll find species from smaller sharks--most commonly the sharpnose shark(s) in the genus Rhizoprionodon which tend to top out at about a meter (3 feet) in size and consequently have some pretty small teeth. Micro-matrix picking also increases the chances of discovering the tiny teeth of rays like stingrays (Dasyatis) which are fairly common, wedgefishes (Rhinchobatus) which are less common (except in Cookiecutter Creek), and oddities like manta and devil ray teeth (Mobula).

 

I'm actually better at identifying rare little micros than many of the larger shark teeth. Just when I think I figure out how to tell one from the other the variations in tooth position (top/bottom and anterior/posterior) confuse me enough to make me toss up my hands and stop at any identification beyond just "shark tooth". I've really come to appreciate Hemipristis serra and Carcharias taurus as these species have quite distinctive teeth. :) Because of the abundance of specimens and the diversity of species in Carcharhinus as well as the difficulty of getting below the genus level, most folks tend to pick a placeholder name for those teeth--"bull shark" or "gray shark" and leave it at that. Trying to ID a partial Carcharhinus tooth to species is generally an impossible task.

 

I'm pretty sure I've seen and collected a number of hammerhead shark teeth but just when I think I understand the significant ID features of these I realize I don't have the first clue. :P I do know that thresher shark teeth are much less commonly collected than most of the other types of shark teeth. Threshers tend to be very open water (pelagic) species often found far from shore and it is not surprising that they are not found with the same abundance of those species found over near shore reef and mangrove areas. Threshers tend to have very curved roots and the can also have quite curved blades. Many species have teeth that have more pronounced curvature to the blades as you move from the central anterior teeth to the posterior teeth in the corners of the mouth. I would suspect due to the relative rarity and lack of clear curved roots that (d-f) above are probably just some sort of worn Carcharinus teeth with busted up roots rather than the more unlikely threshers.

 

Anybody wants to ask me about Cookiecutter Shark (Isistius triangulus) I'd be happy to answer as that's in my wheel house. :)

 

Cheers.

 

-Ken

 

cookie2.jpg    cookiecutter.jpg

 

2019-08-18 21-27-46.jpg    2020-01-04 09-55-01.jpg

 

 

 

  • I found this Informative 2
Link to comment
Share on other sites

7 hours ago, digit said:

larger shark teeth. Just when I think I figure out how to tell one from the other the variations in tooth position (top/bottom and anterior/posterior) confuse me enough to make me toss up my hands and stop at any identification beyond just "shark tooth"

OMG, someone of like experience/frustration with ID'ing shark teeth and willing to state it so clearly! 

I can get so frustrated with the variety of forms and lack of sources (at least in my grasp) to ID the teeth properly, along with similarity of forms across genus that I just give up. :DOH:

I thought maybe there was something wrong with me!  Maybe I was just not as "bright" as I'd thought.  (That, of course, could still be true. :headscratch:)

It's so nice to see someone whose expertise I respect claim similar difficulty.  Perhaps there's hope for me yet.(?) :shakehead:

Link to comment
Share on other sites

7 minutes ago, grandpa said:

Perhaps there's hope for me yet.(?)

Or there is no hope for the both of us. :P

 

My shark tooth knowledge ebbs and flows like the tide. Some days I think I've got things sussed and then I see a tooth that collapses my house of cards. I know enough to know that I know very little. ;) (But that leaves ample room for improvement.)

 

 

Cheers.

 

-Ken

 

P.S.: I am getting very good at identifying teeth that virtually nobody else finds--Mustelus sp. and Mobula (Manta) birostris and M. hypostoma and I'm really good with lower posterior Sphyrna tiburo (Bonnethead Shark) teeth. I'm becoming quite the king of my own little mole hill. :blink:

Link to comment
Share on other sites

Sometimes it is not easy to identify whole teeth, it is even harder to identify (with confidence) broken and worn teeth. The roots help on many IDs, but so many are missing.

They look like a bunch of broken and worn Carcharhinus teeth to me.  I've seen a lot of people call lower Carcharhinus teeth "Lemon Shark" teeth.  Lemon sharks have

no serrations and Carcharhinus do. Hammerheads can look like a Tiger Shark without serrations.

carcharhinus-shark-tooth1.jpg

carcharhinus-shark-tooth2.jpg

hammer_tooth_id.jpg

  • I found this Informative 2
Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...