The Post Pliocene Giant Macropredatory Sharks: Survivors of the Late Pliocene extinction event

[Joseph Fossil]

The era between the Miocene and Pliocene (23-2.3 Million Years ago) was, like the Carboniferous era 300 Million Years before, a golden age for the Chondricthyans. Not only was there a massive explosion in the diversity of grey sharks, but there was the emergence of perhaps the largest number of large macropredatory shark genera (sharks greater than 3 meters (10 feet) in length) currently known in Earth's geologic history. This includes the Giant Thrasher Shark Alopias grandis (which grew up to 13 meters (feet) in length) and the famous Carcharocles (Otodus) megalodon (which grew up to 17 meters (55 feet) in length).

 

https://www.science.org/doi/10.1126/sciadv.abm9424

 

But this golden era of the giant macro predatory sharks wouldn't last, for between 3.8-2.4 Million Years ago there was an extinction event of large marine fauna that killed at least 14% of large marine fauna genera, including Carcharcoles (Otodus) megalodon. Though it's not entirely clear what caused this extinction event (some have hypothesized it could've been a mild gamma ray burst), C.megalodon's decline was due to the closing of the Isthmus of Panama by 4.5 Million Years ago (an area that was a C.megalodon nursery), a decline in diatoms that caused a decline in the food sources of many whales like Cetothere whales including Cetotherium (a known food source of C. megalodon), and Competition with the recently emerged Great White Shark (Carcharodon carcharias) and Orcas (Orcinus). By the extinction events end, most of the Miocene's large predatory sharks were extinct.

 

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6377595/

 

https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0084857

 

https://www.researchgate.net/publication/318160879_The_Pliocene_marine_megafauna_extinction_and_its_impact_on_functional_diversity

 

https://royalsocietypublishing.org/doi/10.1098/rsbl.2020.0746

 

But there was a few genera that survived the extinction event 3.6-2.4 Million Years ago and lived long after it. These surviving taxon (likely surviving due to relying on different food sources then other large sharks of the miocene-pliocene) lived previously alongside C. megalodon and some survived up to at least the early Pleistocene (120,000-100,000 years ago). Here's a list of the large (non Great White Shark (Carcharodon carcharias)) macropredatory sharks of the late Pliocene-Early Pleistocene (If I'm missing any examples, let me know and I'll quickly add them).

 

 

Hemipristis serra (Hemigaleidae, grew up to 3-5 meters (10-16 feet) in length) (Miocene-Pleistocene (Pleistocene strongholds: What is now Indonesia, Taiwan, South Carolina (U.S.), Alabama (U.S.), and Florida (U.S.)), 23.03-0.012 Million Years ago)

 

Reconstruction 1 and 2

Image by artist @Tetrtophoneus, Image credit: https://www.deviantart.com/teratophoneus/art/Hemipristis-serra-871902574

 

Image by artist @HodariNundu (the two sharks below and next to the juvenile C.megalodon at the middle top are adult Hemipristis serra), Image credit: https://www.deviantart.com/hodarinundu/art/Mobbing-Meg-885731702

 

http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=83182

 

https://www.fossilguy.com/gallery/vert/fish-shark/hemipristis/hemipristis.htm

 

https://www.researchgate.net/publication/364591134_A_previously_overlooked_highly_diverse_early_Pleistocene_elasmobranch_assemblage_from_southern_Taiwan

 

 

 

Parotodus benedeni (Otodontidae, grew up to 7.6 meters (24.9 feet) in length) (Oligocene-Pleistocene (Pleistocene strongholds: What is now South Carolina (U.S.)), 33.9-0.012 Million Years ago)

 

Reconstructions 1 and 2

Image by artist @imAdro, Image credit: https://www.deviantart.com/imadro/art/Parotodus-benedeni-908901669

 

Image by artist @SameerPrehistorica, Image credit: https://www.deviantart.com/sameerprehistorica/art/Parotodus-Size-882947974

 

 

http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=389883

 

https://www.petit-fichier.fr/2013/01/27/kent-b-w-1999-taille-parotodus-benedenii/?

 

https://www.researchgate.net/publication/337937278_2019-canevet-a-review-of_the-extinct-genus-Parotodus

 

https://www.app.pan.pl/archive/published/app63/app004542018.pdf

 

http://www.fossilworks.org/cgi-bin/bridge.pl?a=collectionSearch&taxon_no=389883&max_interval=Quaternary&country=United States&state=South Carolina&is_real_user=1&basic=yes&type=view&match_subgenera=1

 

https://www.cambridge.org/core/journals/paleobiology/article/chondrichthyan-fossil-record-of-the-florida-platform-eocenepleistocene/2835CCEC27DC8EE0B24A5B62B1416618

 

 

 

Cosmopolitodus hastalis (Lamnidae, grew up to 5-7 meters (16.4-22.9 feet) in length) (Oligocene-Pleistocene (Pleistocene strongholds: What is now Japan, South Carolina (U.S.), Alabama (U.S.), and Florida (U.S.)), 30-0.012 Million Years ago)

 

Reconstruction

Image by artist @artbyjrc, Image credit: https://www.deviantart.com/artbyjrc/art/Going-to-need-a-bigger-boat-Lamnid-sharks-837971394

 

 

http://www.fossilworks.org/cgi-bin/bridge.pl?a=taxonInfo&taxon_no=265174

 

https://actapalrom.geo-paleontologica.org/Online_first/Chan_Cosmopolidus_planus.pdf

 

Note: Cosmopolitodus hastalis was an ancestor to the extant Great White Shark (Carcharodon carcharias), along with living alongside the Great White Shark (Carcharodon carcharias) between the Miocene-Pleistocene. However, Cosmopolitodus hastalis’s being a member of the genus Carcharodon has yet to be confirmed).

 

 

I hope you all find this helpful?

 

 

[Mikrogeophagus]

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