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@walter-stein, I went to Montana State for my undergrad–I was a (modern, not ancient!) history major though! Then I did my masters at Montana State for Science Education. I worked in the Museum of the Rockies education department throughout my undergrad and for a year during my masters before moving to Florida. Bozeman is one of my favorite places on earth!
Thanks for the info about the dry screen. That’s pretty cool to see the passage of time/work through the location of the screen. And that sounds like an amazingly productive quarry to be working in. Are there you finding a lot of teeth from different theropods, or are they from just one species?
Here’s a photo of one of my favorite finds from yesterday in Lago Alajuela, Panama (sorry for the lack of scale it’s between 2 and 3 inches)
Here is the very last fossil I found while in Panama, in the last seconds we were in the field. A beautiful, complete Megalodon tooth in situ. I was so excited by the find that I had to go collecting when I got back to Florida, so the 2nd picture is of a sand dollar from Hogtown Creek in Gainesville, FL that I found a couple days after we got back.
I took a trip to Rattlesnake Creek here in Gainesville over the weekend with some geology grad students (@smoran @bostickkw). Here’s a picture of my finds from the trip. Lots of dugong bones and shark teeth.
@vperez, @smoran, @bostickkw Nice! Looks like Hurricane Hermine was productive for Rattlesnake Creek. I was reading in some of the Facebook discussions for the Florida Fossil Hunters that it wasn’t as good for other creeks in Gainesville.
Took a trip to Hogtown Creek yesterday and found a few interesting things. Cetacean vertebra, croc tooth, echinoid, pufferfish dentary, and some cool modern bones and jaws. Attached is an overview shot and a close up of a modern pig jaw.
In honor of the “She’s A Scientist – A Girl Scout Exploration” event at FLMNH this coming Sunday, Nov 13, here is a photo from when I participated in an NSF research cruise out of Woods Hole Oceanographic Institution. I was part of a team collecting live foraminifera from seafloor sediment samples, for the purpose of conducting taphonomy experiments. The experimental results were then compared to fossil forams. The research project was headed by two women — Dr. Sue Goldstein from the Univ of Georgia and Dr. Joan Bernhard from WHOI. It was a neat experience, other than the horrible storm and resulting 18-foot waves we endured for 3 days… 😉
@vperez Victor, so are you saying the black jaws are modern as in not fossils or fossils of modern species? Jack
@jkallmeyer sorry for the confusion! I meant modern as in sub-fossil, probably hundreds of years old rather than thousands to millions of years old.
@vperez Victor, help me out here. I’m not used to Florida fossils and I was under the impression, apparently incorrectly, that all the black “fossils” were actual fossils of significant age. Since that doesn’t appear to be the case, why are these black?
Jack
@jkallmeyer. This is a pretty common misconception. The coloration of a fossil (or sub-fossil) is controlled by the surrounding sediment. The rate at which sediment becomes incorporated depends on a number of things from the porosity of the object to the chemistry of infiltrating water. You can also have superficial color changes from chemical weathering. I tend to advise against using color as a tool for identifying fossils because of how variable it can be. Here are a few tricks for determining if a bone is a fossil:
- You can a sound test. If you tap two fossil bones together, it sounds similar to tapping two ceramic pieces together. This is because fossil bone is typically ‘permineralized’, which basically means it has been infilled with minerals. Bone that hasn’t been permineralized will have a dull sound, similar to tapping two pieces of wood together.
- You can do a weight test. Another consequence of permineralization is that the bone becomes much denser. So sometimes just feeling the weight in your hand is enough to tell if you’ve got a fossil bone.
- You can do a burn test. Light a match under your bone in question. If it smells like burning hair and leaves a scorch mark, then it’s probably not fossil. Modern bones have collagen, which is what gives the burning hair smell. In fossil bones, organics like collagen are typically degraded.
These aren’t definitive methods, but they hold true in most scenarios. The section of pig jaw I found is very light and from the cross-section where it’s broken you can see the black is just a surface feature. There is no way anyone could tell that from the pictures I posted though and, I will admit, a few people at the museum thought it was fossil at first.
Here are some photos from my trip to Oregon in August, during which our main goal was collecting Metasequoia leaves for K-12 education kits. You can see the full album on the FOSSIL Project facebook page https://www.facebook.com/173936902809060/photos/?tab=album&album_id=522178957984851
@acurrier have done any more collecting recently?@vperez Thank you for your post on how to determine if a bone is a fossil. I still have some questions. Is there a different set of diagnostic tests for individual mammal teeth? If the item is a mammal tooth with enamel, and the enamel is still partially white, does that rule out the possibility of it being a fossil? Would the burn test be used? Weight would be hard to compare because enamel would be heavy to start with and the “tap” test seems like it would be dangerous to use on enamel. What tests would you use?
Also, I have a question about the nomenclature of the word “domestic” when used in the identification of a fossil. I found a tooth in Greens Mill Run several months ago and was told it was probably a Sus scrofa premolar or a domestic pig premolar. Does the “domestic” title mean domesticated by humans or domestic by location? Fossil or not fossil? I have so much to learn! Thanks for your help!
@julie-niederkorn, teeth can be a little more challenging than bone. Teeth do become denser as they incorporate more sediment, but the density difference between a modern and fossil tooth isn’t as a great as it is between modern and fossil bone. The tap test doesn’t work because enamel will make that ceramic sound regardless of it being modern or fossil. The burn test can be done by burning parts of the root rather than the enamel itself, but it doesn’t work quite as well as it does for bone. The coloration doesn’t help much for teeth either because the rate of color change is highly variable and depends more on the environment than the fossil itself. For example, if a tooth sits in the sun for a long time, it can be bleached white despite being a fossil. Long story short, it can be a lot more challenging to distinguish a fossil tooth from a modern tooth. I’ve been collecting in the Gainesville creeks which have fossils from 40 million years ago to animals that just died yesterday, so I’ve been struggling with distinguishing modern versus fossil teeth as well.
As for the domestic question, I’m not quite sure. I’m pretty sure, Sus scrofa is commonly called the wild boar and Sus scrofa domesticus is a sub-species for the modern domesticated pig (some call it a separate species Sus domesticus). It’s very hard to say if your tooth is a fossil, but it certainly seems old from the picture. Admittedly, I don’t know much about the fossil record of pigs, but perhaps some others know more. @bmacfadden @smoran @jnance any thoughts on this?
Hope this loaded! I was on a dig with the Southwest Paleontological Society in Chinle Valley, Arizona. Found some great specimen from that trip!
@mackenzie-white yes! it loaded just fine. The spot you’re in looks a bit like some of the stuff we were working on in Nebraska a few summers ago! The was in Cenozoic deposits, and we found a lot of turtle fossils, but some mammal remains, too. I attached a photo here where you can see the geology, and how the patterns on the surface kind of look like your photo. (As an aside, the person in the beige shirt near the bottom was our latest webinar presenter, @rnarducci ) I’m not very familiar with Chinle Valley. I see the post tagged with Triassic and Teeth. Is that the age of the rocks? What species of teeth did you find?
@llundgren The Chinle Formation is a Late Triassic geologic formation. I found some Metoposaur teeth as well as Phytosaur teeth. I also found a few fossilized osteoderms from early crocodiles. You can look at my fossils on my profile page. We were actually on the outskirts of a landfill in Chinle Valley, Arizona. The landfill was surprisingly beautiful with all the rich colors of the rocks. If you look at pictures of the formation you’ll know what I mean! Thank you for your feedback!
@mackenzie-white whoa! I just googled the Chinle formation, it looks stunning. Hah, when I read that you all were collecting on the outskirts of a landfill, I was immediately reminded of a field course I took with my class at Montana State University. We were in eastern Montana, close to the town of Glendive, and also found some great fossils from the late Cretaceous (one classmate found part of a Triceratops horn) on the landfill outskirts!
@egardner we need to talk with the Southwest Paleontological Society so we can do a mini conference or go to the section meeting for GSA out there! New ages of fossils, amazing looking landscape.@llundgren, @mackenzie-white: Wow, you guys are right – the Chinle Formation is stunning! I like the idea of possibly doing a mini conference with the Southwest Paleontological Society or connecting with a regional GSA section meeting. Looks like the Chinle Formation is technically in the Rocky Mountain Section of GSA, while the rest of Arizona is in the Cordilleran Section. (Weird that they split a state between sections!)
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