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Fossil sharks from Capitola–
I think that the two sharks that we should put in the general study kit should be–
Megalodon
Hexancus (I wonder if we could get these from Gordon); OR perhaps we could put a call out to the myFOSSIL community (Lisa)?And, I think Victor we could do a really great other lesson plan on the one you have already done with the origin of Great whites–adapted to Capitola. Both Meg and extinct Great whites occur in the Purissima Fm.
Sean–how many crab claws do you have from Capitola?
Hi Bruce, I agree there is definitely potential for other interesting lessons. Your comment on the presence of both Megalodon and the Great White made me think of the Tamiami Formation here in Florida. When I went to SMR with Roger, I was told that both could be found there as well. I would need to go back and look at the actual ages of the Tamiami and the Purissima formations to see how well they correlate, but the two may offer an interesting comparison of the Atlantic vs. the Pacific at a time when the marine connection between the two was no longer present. Likewise, this could be expanded to other taxa as well.
Also, I believe when Sean and I went to Capitola I collected a couple of crab claws that I gave to Roger. So we should probably check our own collections here at UF to see what else we’ve got from there.
Bruce, I think Megalodon and Hexanchus would be great to include in the Capitola study. It would be beneficial for the students to be introduced to vast differences in shark dental morphology. I am just a little worried that we are going to struggle to find enough Hexanchus specimens to include, but perhaps not.
Re: Capitola crab claws. I am not sure if brought any back to the east coast with me…and if I did how many. Let me poke around a little bit and I will get back to you.
These look great, @bmacfadden! I think there are quite a few specimens in there that will be of use in the study sets. If I remember correctly the color of the enamel tended to be a deep gray with a lighter gray to tan root. Does this sound right, @vperez? I can’t remember if we saw any teeth on the trip we took to Capitola.
Hey Sean, I don’t remember what the teeth looked like. I don’t think we found any shark teeth while we were out collecting. You may have shown me the Hexanchus that you found when I helped you move, but I don’t actually recall the coloration. I may have some Hexanchus teeth from the Calvert Cliffs that could be used, but obviously they would be very different in age (not sure if that’s a problem?). The teeth I have are my parents’ house in Maryland, but I can pick them up over Thanksgiving break. We only need six of them right?
Actually, on second thought, the teeth I have from Calvert Cliffs are that of the similar looking Notorynchus primigenius. Despite their similar appearance, they are probably too different to include in the lesson.
Hi all,
Bruce invited me to join the forum – I’ve done quite a bit of field work in the Purisima Formation, mostly going after fossil vertebrates (my focus is marine mammals) but I am very familiar with the inverts as well and my master’s thesis (published last year in PLOS One) considers the marine vertebrate taphonomy of the unit. Capitola is one of the taphonomically more informative localities as it spans inner-middle shelf depositional settings. Also, I’m quite proud of the fact that in 2004 I helped others in Santa Cruz county stop a seawall from being built that would have covered over this entire locality – so I am absolutely pleased to hear that you all have started using it as a “teaching laboratory” for educational purposes.
Bruce, I see plenty of Anadara trilineata in that collection of mollusks you received. I may be able to make it down to Capitola while I’m home for Christmas, but more likely than not I’ll ask a couple of my buddies in the area who are dedicated, informed amateurs to collect some of the other more common invertebrates.
As for sharks: rare Carcharodon carcharias teeth can be found in a couple of the horizons, but no Carcharocles megalodon; only a single tooth has been collected from the Purisima, and I collected it from a different locality that is geochronologically older (~7 Ma, as opposed to the ~2.5-5 Ma section at Capitola).
I am more than happy to answer any questions you guys have – please pick my brain! This is one of my favorite localities, and I’ve been visiting the spot since I was in high school ~14 years ago. Cheers, Bobby
@rboessenecker @smoran @vperez
I had a nice meeting with Frank Perry who wrote the pub on Capitola fossils.
I also have heard from Gordon Hubbell that he does not have any Hexanchus teeth that we could use for our study sets. We may need to swap out for another species of shark that is found in the Purissima.
@vperez @smoran @rboessenecker
Capitola sharks
Hi all–I took a photo of the shark tooth exhibit at the SC Nat History Museum. It shows that there are Megs, for sure. Plus Carcharinids. Perhaps those are the two teeth we should feature in the Capitola lesson plan. Please look at the color of the teeth and lets see if we can get close.
@acurrier @smoran @cgrant @llundgren @egardner
Thanks to Aaron Currier for the offer of some Metasequoia fossils for these kits.
I’m therefore thinking of expanding these kits from a more narrow focus of just the fossils from Capitola Beach to be more broader and include a set from the Santa Cruz region. And given the brainstorming with the GABI-RET teachers last weekend, the Metasequoia fossils can give them a sense of the antiquity of these beautiful trees. I’m also going to include a fossil Equus tooth. These horses were common here during the Pleistocene.
more later, Bruce
PS–could someone tell me how the “Tags:” below actually function?
@bmacfadden – This is a great development!
Regarding your question about “Tags,” as Eric has mentioned before, they are simply a way to organize posts. Here is some language from the WordPress.com support site: “Tags provide a useful way to group related posts together and to quickly tell readers what a post is about. Tags also make it easier for people to find your content. Tags are similar to, but more specific than, categories. The use of tags is completely optional.” On our wishlist of updates/improvements, we have asked Eric to add an explanatory note beside the “Tags” field so that users know how and why to use it. Hope this is helpful!
Hi–
Went out to Capitola this afternoon to look for some ghost shrimp claws for a study kit. It had just rained and there was seaweed and kelp covering everything on the beach. Could not find any.
Do you have 4 to 6 of these fossils that could be donated to the K-5 lesson plan? I know that they are common, but I’ve come up short.
Let me know please–thanks, Bruce
Could you push out the following request to the community via FB, or Twitter:
“Bruce MacFadden is looking for six fossil sand dollar (Dendraster) specimens for a elementary school fossil study kit in California. If you have these, or know of a source, let us know. Thanks–”
It would be great if this could work. Thanks–Bruce
Hi @bmacfadden – I’ll be visiting California for the holidays Dec 17-Jan 4, and might have time for a trip to pick up some supplementary fossils for your educational packages. Thalassinidean shrimp claws are fairly easy to find, but only within two bonebeds, which take a bit of practice to spot – I’m happy to pick up a bunch for you. The Dendraster request will be tough to fill, simply because A) they are present only within vertical cliff exposures that are illegal to dig into (boulders on beach OK, but cliff is off limits) and B) the matrix is notoriously difficult to remove and sort of requires abrasive preparation and sanding/polishing.
Again about the sharks – the exhibit at the SC Natural History Museum is on sharks from the stratigraphically lower Santa Margarita Sandstone in Scotts Valley – not the Purisima Formation. Carcharocles megalodon is only known from two specimens in the Purisima, one of which is in a private collection and the other of which is a specimen I collected at a separate locality that is geochronologically older – so in my opinion, it’d be better to stick with Carcharodon carcharias teeth rather than C. megalodon teeth for the kits. The sharks that are by and large the most common are Carcharodon carcharias, Hexanchus sp., and Myliobatis sp. Actually, Myliobatis is far more common than all other elasmobranchs combined. Cetorhinus gill raker fragments are found semi regularly; a single tooth has been collected. Alopias and Carcharinus are known from the Purisima Formation at Capitola by a single tooth each (SCMNH collections); I’ve found additional isolated teeth of Raja, Galeorhinus, and Dasyatis by screening bonebed matrix from Capitola. And that’s effectively the extent of the elasmobranch fauna of the Purisima at Capitola. I hope that helps.
Hi Bobby–Thanks for the response. I’m bummed because I leave for Berkeley on the 16th and then go back to Florida for the holidays. Then we are moving back to SC for 9 weeks on 9 January. So I will not see you.
If you could find some (4 to 6) ghost shrimp claws for the the fossil study kit, that would be great. There was a storm here two nights ago (lots of rain). I went to Capitola yesterday afternoon to look for the ghost shrimp, claws, and I could not see much because the beach was littered with seaweed and kelp. Or perhaps even though they are easy to find, I don’t yet have the eye for them.
I have decided to expand slightly the focus of the K-5 study kit from just Capitola to the Santa Cruz region. It allows me to bring in some other kinds of fossils to tell a broader story.
All the best, Bruce
Hi @bmacfadden, sure thing – I may be going to Santa Cruz tomorrow, and if so, will collect some calianassid claws; or, if not tomorrow, sometime later in the week. Any other requests for other invertebrates? I could probably include some whale bone fragments as well.
Also for some weird reason I can’t see any text in this text box while I’m typing – the text color comes in as white. Any tips or is it just broken?
@rboessenecker – The issue with white text or text that you cannot see while typing is a bug and we are working to fix it ASAP.
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