• Jacob Quentin Mullins Polzin posted a new specimen. 1 year, 10 months ago

    1 year, 10 months ago
    1 year, 10 months ago

    Jacob Quentin Mullins Polzin has contributed specimen mFeM 81855 to myFOSSIL!

    • C. perezii

    • I updated this. Can I ask why this tooth has an extended root with serrations? It doesn’t seem to match othe carcharhinus examples I’ve seen because of the odd extension. Also, do the vast majority of carcharhinus specimens from calvert belong to the species perezii? I’ve seen several species listed as being obtained there and a couple look very similar to perezii. Are they synonyms for perezii? @bill-heim

    • The old classifications were inconsistent from specimen to specimen often because they did not take into account of the teeth shape varying in different parts of the jaw. Fortunately I have jaws of the majority of Carcharhinus species (along with most other encountered sharks) to compare with. The Miocene specimens do not 100% match the modern teeth mostly in that the serrations are often not as strong (their Eocene ancestors had unserrated blades) however, they are a 95% match which is close enough. The Caribbean Reef Shark is very common tropical and subtropical shark. This along with crocodile specimens from this area indicate that the climate at the time was warm year round (crocodiles cannot endure freezing temperatures unlike alligators). This tooth has an unusual shoulder which is possibly pathologic. I have a jaw of a grey reef shark which is missing one file of teeth. The tooth file next to the missing file have similar pronounced elongated shoulders. Unfortunately, I cannot add images to illustrate my statements.

    • Awesome! Thank you so much for the info, I really appreciate it. @bill-heim