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Thought I would share with you folks a little project I just finished up... until next field season starts. Last spring/summer I collected from two Eocene sites where I have found small mammal teeth in the past in the hopes of finding more small teeth (and bones). One site I screen wash; I quarry on site and find largeish bones and then scoop up the stuff I have excavated for screen washing. The highlight of in situ quarrying last spring was three turtle scapulae and a very small mammal maxilla. I screen wash it twice. A five gallon bag will break down to about a pint (not sure the metric equivalents) of rocks and fossils. Lots of broken pieces and lots of fish bones, and some reptile pieces such as lizard jaws and snake verts, and then a few mammal teeth. The other site is a quarry; I sit there and break rocks looking for little fossils then prep them under the microscope when I get home. I got about 30 mammal teeth and one jaw with two teeth in it that day. To organize the collection, I mount them on toothpicks and store them in 2 inch square plastic boxes. (Numbers 121 and 122 are yet to be found). Then I take photos and create stereophotos of each tooth. I am a big fan of stereophotos so get a kick out of this. Here are some pix for you all to look at. I have shown stereophotos here before, and there are instructions online on how to see them, but the basic idea is to relax your eyes let the two images merge into a middle image and then focus on that middle image. It will pop put at you in 3D. Or you can use a stereoviewer if you have laying around. (Tool's last cd came with one as one of the band members is also a 3d fan as is Brian May of Queen). I confess that my specialty is finding and prepping. I am not an expert at IDing these things, but where I can say something about the photo, I will. Each of these specimens is measured in millimeters and mounted onto a round toothpick. No scale bar, but the toothpick is about 2mm in diameter and will give you an idea of size. I take the photos through the eyepieces on my microscope. I do not have photostacking software so many have focus issues. In a perfect world I would also take pictures form the sides of some of these, but hey, there are more fossils to work on. The teeth are all seen looking at the occlusal (=chewing) surfaces The first batch of teeth are from the Washakie Fm of Sweetwater County, Wyoming. Bridgerian (middle Eocene) in age. These are the screenwashing finds 1. This is a very small upper third molar of a carnivorous or insectivorous mammal: I found this tooth in two pieces. Yo can see the glue line at the base of the high peak. 2. an upper molar 3. another upper molar 4. a rodent? sacrum; two fused verts: ( a contender for coolest fossil of the year) 5. A very interesting ungual. I have not seen this sort of toe bone before but I actually found two of these in my screen washings this fall. 6. This is the mammal maxilla that I found in the field. It includes two molars and a premolar. This is a strong candidate for my best find of 2023. 7. And this is a lower jaw with one molar. The next batch are from the quarry site in the Wind River Fm of Fremont County, Wyoming. They are early Eocene, probably Wasatchian in age. 8. another upper molar 9. a small astragalus 10. and still another upper molar 11. a very small premolar 12. A third lower molar 13. I think this one is a rodent molar And that's it for now Thanks for looking.

I noticed that in the wide world of vertebrate paleontology, not a lot of attention is given to India, despite some rather good Mesozoic (notably Triassic) vertebrate sites. I thought it would be nice to share this with the other TFF members, to promote a bit the advances in Indian vertebrate paleo: https://www.researchgate.net/project/Mesozoic-Microvertebrates Some of the papers have the full text available. What do you people think? -Christian

Hi, I recently finished processing 4kg of matrix from a horizon in the Upper Hamstead Mbr. of the Bouldnor Fm. from Bouldnor Cliff and thought I'd share the results! The White Band is definitely the most diverse vertebrate fauna I've collected so far in my short time screen washing, with at least 2/3 genera of fish, 2 genera of reptiles, and 2 genera of mammals, it also has some interesting taphonomy. The White Band refers to a thick Polymesoda shell bed in the Upper Hamstead Mbr. and dates to approximately 33 million years bp during the Rupelian. The Upper Hamstead Member is the youngest strata in the entire paleogene sequence of the Hampshire Basin (Late Palaeocene to Early Oligocene). The horizon was deposited in a shallow freshwater lacustrine environment on the low-lying Solent Group coastal plain of the southern Hampshire Basin. By the time the White Band was deposited average annual temperatures in the region were beginning to warm up again after the sudden and rapid cooling that marked the Eocene-Oligocene transition. Global sea levels were also beginning to rise. The Grande Coupure, the large scale turnover of European mammalian faunas had been and gone, and the endemic Eocene groups such as Palaeotheres, Omomyid primates, and anoplotheres had long vanished. The lake/pond system that deposited the White Band was home to aquatic plants such as Stratiotes and was fringed by patches of open woodlands of Sequoia, Pine, and broadleaf. With the post-grande coupure fauna now established the landscape was home to anthracotheres, hornless rhinos, hyaenodonts, bear-dogs, entelodonts, primitive ruminants, choeropotamids, and a myriad of smaller mammals including bats, adapid primates, rodents, insectivores, marsupials, and the otter-like pantolestids. Not to mention the alligators, birds, and freshwater turtles. 1. Worn fragment of Emys carapace 2. Possible fragment of crocodilian osteoderm? 3. Fragment of Bowfin skull bone 4. Isoptychus sp. cheek tooth. Theridomyid rodents like Isoptychus are the most commonly found micro-mammal throughout the entire Solent Group. This molar has been heavily worn which may suggest an older individual. Theridomyids were bipedal and foraged along the ground and in low trees. They also seem to have fed on the seeds of marginal aquatic plants such as Stratiotes, which may be the reason this individual was in the vicinity of the pond/lake. The Theridomyids were one of only a few Eocene mammal groups to survive the Grande Coupure and seemed to have survived fairly unscathed in terms of diversity etc. showing what hardy and adaptable rodents they probably were. 5. Fragment of M3 from a talpid, most likely Myxomygale sp. (just 1.5mm long!). Talpids (or as we call them today, Moles) were newcomers to Europe with the Grande-Coupure, arriving from Asia. Belonging to the tribe Urotrichini (Shrew-Moles) which are only found in North America and Asia today, Myxomygale may have spent most of the day underground in burrows before emerging at night to feed on invertebrates. Modern Shrew-Moles prefer moist habitats such as swampy areas, a habitat which was abundant on the low-lying coastal plain of the Oligocene Isle Of Wight. The taphonomy of the White Band is also interesting. Some specimens i.e. the Emys fragment and osteoderm are highly 'polished' and worn, suggesting transport prior to deposition. Whereas others such as the mammals and most fish material I've recovered are unworn and 'fresh' looking. I'm not sure what conditions could have caused this, and if anyone has any suggestions I'd be really interested. My take is that the mammals and fish were likely living in the immediate area, in and around the lake/pond, whereas the polished material is from animals living some distance away brought to the pond/lake by floods or streams etc. although I'm no trained geologist or palaeontologist. Thanks for reading, Theo