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Showing results for tags 'tympanic'.
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New blog post! A guide to whale and dolphin earbones - part 1
Boesse posted a topic in General Fossil Discussion
Hi all - it's been a while, since I started on twitter and started teaching much of the itch I scratched through blog writing was taken care of by twitter - but now I've thought about returning to more long-format science communication. The blog format is certainly more informative for most fossil collectors anyway. The new post is just the first in a series on whale and dolphin earbones - the first is an introduction to the basic anatomy and function of earbones, along with basic differences between baleen whale (Mysticeti) and dolphin (Odontoceti) earbones, with comments on their preservation, discovery, and their uses in cetacean taxonomy, cladistics, and studies of diversity. The next post will be the one most anticipated by the majority of collectors - a guide to identifying dolphin periotics by family. The third post will be similar, but directed towards mysticete periotics, and the fourth will cover mysticete and odontocete tympanic bullae. Read it here: https://coastalpaleo.blogspot.com/2022/12/bobbys-guide-to-whale-dolphin-earbones.html Obligatory photo of some periotics we collected out on Charleston harbor on Dec. 1, well worth boots full of freezing cold water: -
Hi, just going through some rocks I brought back from Norfolk, UK, thinking quite a few may be fossils (I didn't have long so just grabbed anything I thought looked suspiciously organic by intuition) and as it turns out I think I was quite correct in a number of cases - I think I have quite a few pieces of whale and and a few little bits of mammoth tooth. Trying to confirm this to myself led to a lot of reading and learning online about the local geological formations involved and also whale anatomy, both new topics for me which I always enjoy delving into - part of the enjoyment of fossil hunting for me - I'm less of someone looking for beautiful specimens for display (though I'm not going to turn those down!) and more someone who loves the detective work of trying to identify obscure parts and recreate some aspect of the vanished world before us from its traces. And searching through whale anatomy and what these weird chunks could be I came across a picture of a whale periotic and realised that the weird little pot structure I had was almost definitely one of these, which if I am correct is good because I believe they are one part of a fragmented whale anatomy that is quite diagnostic. Also I then realised that a strangely hooked piece I found right next to it could well be the tympanic! The preservation here is unusual because many theorise that these kind of whale fossils were first laid down in sandstone in the Miocene when Norfolk was covered with a shallow warm sea, and then later in the Pliocene and early Pleistocene when temperatures dropped sea levels dropped too and the area became land (part of the reason the geology of this area is interesting is the constant transgression and regression of the sea over a few million years), these Miocene rocks were eroded away and the harder fossils reworked into new estuarine or nearshore sediments of this era, often but not always with a layer of hard iron-rich concretion coating them which helped protect them (I guess one question would be, is there anyway of easily removing this hard concretion layer?) So if I am right, these are bones from Miocene whales (many showing signs of shark damage), reburied in the Pliocene / Early Pleistocene and then finally eroded out again in the modern day - quite a journey! Anyway, enough background, for starters I'd love to see what people think about this periotic / tympanic. Am I right? Here's a summary of my findings (note I used a pic of dolphin periotic someone posted here for comparison so I hope that isn't too cheeky)