Megalodon not as big as we once thought!

[BorneanTiger]

(09-15-2020, 08:07 PM)GuateGojira Wrote:

(09-14-2020, 03:25 PM)BorneanTiger Wrote: I have discovered that it's not even as simple as that, because for instance, another prehistoric mega-toothed shark that is considered to be a close relative of Megalodon (hence considered to belong to the same genus as Megalodon) is Carochles angustidens / Otodus angustidens, and in 2001, the discovery of what was said to be the best-preserved angustidens specimen to date by two scientists, Michael D. Gottfried and Ewan Fordyce, had been presented by the team as evidence for close morphological ties with the extant great white, and so the team argued that angustidens (along with all other related megatooths, including Megalodon) should have been assigned to Carcharodon, as was done before by Louis Agassiz: https://www.tandfonline.com/doi/abs/10.1...2.0.CO%3B2

Basically, the issue of which shark is closely or distantly related to the Megalodon and other megatooths is a controversial topic, with different models of evolution giving different answers.

A tooth of Carcharocles / Otodus angustidens measuring 4.25 inches (10.795 cm), found in the Edisto River of South Carolina's Lowcountry, image by user Crazy Uncle Jim (16th of August, 2007):

*This image is copyright of its original author

2 teeth belonging to another species (Carcharocles / Otodus auriculatus): USNM & PAL-537807. Credit: E. Emmons (1858), North Carolina Geological Survey Report, pages 231–234, Figures 57–58; P. Bartsch & A. R. Barwick (1941), Copeia (1): 40–41; from Craven County, North Carolina; posted by The Smithsonian (2nd of June, 2009): https://collections.si.edu/search/detail...term=shark

*This image is copyright of its original author

A tooth belonging to Carcharocles / Otudus sokolovi from Dakhla (Morocco), measuring 3 inches (7.62 cm), with a feeding damage to the tip and some "lightning strikes", image by user Whodaman HD (11th of December, 2019):

*This image is copyright of its original author

A chipped tooth belonging to Carcharocles / Otodus subauriculatus (also chubutensis), which was thought to have evolved into Megalodon. Dated to the Early – Middle Miocene (~ 18–15 million years ago), it had a slant height of 2.25 " (57 mm), and was found by Jayson Kowinsky (2011) in Chesapeake Bay Area (on the border of the States of Maryland, Virginia and Delaware): https://www.fossilguy.com/sites/calvert/calv_meg.htm

*This image is copyright of its original author

Lingual and labial view of a lateral tooth belonging to a Megalodon, which was found by Kowinsky at Calvert Cliffs, in Maryland's portion of Chesapeake Bay. Dated to the same period as above, it had a slant height of 2 ⅜ " (60 mm):

*This image is copyright of its original author

A tooth of the Megalodon with 2 teeth of the great white, by user "Broken In a Glory":

*This image is copyright of its original author

Did you notice that the article is from 2001? That information is now outdated and do not apply to "megalodon" anymore. Current consensus is that "megalodon" is not related at all with the modern white shark and even they tooth are very different, as we can see in your last picture.

Though they are different, the teeth of the great white look more similar to those of C. / O. subauriculatus (chubutensis) than to those of these mako sharks (genus Isurus), and the teeth of the latter look more similar to those of a number of megatooths shown here, even though both the great white and mako are mackerel sharks (order Lamniformes) which are outside the genus Otodus, and the others are megatooths which are supposed to be in the same genus as Megalodon, that is Otodus (or formerly Carcharocles), and consensuses change over time, like about how ape-like or human-like Lucy the australopithecine was.

The jaws of a shortfin mako (Isurus oxyrinchus) from the Northern Atlantic, by Didier Descouens (8th of March, 2012):
   

The jaws of a longfin mako (Isurus paucus) from the Greater Caribbean, by D. Ross Robertson of the Smithsonian Tropical Research Institute: https://biogeodb.stri.si.edu/caribbean/e.../specie/52
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