Megalodon vertebra?

[todd lewis]

So as young as this vertabra reads it seams big but how large would a 15 year great white be on average?

[Randyw]

Male white sharks reach sexual maturity at 3.5 to 4 metres (about 11.5 to 13 feet) in length and about 10 years of age, whereas females reach sexual maturity at 4.5 to 5 metres (about 15 to 16 feet) in length and 12 to 18 years of age.

with a 20 footer being believed to be 40-50 years old from a couple of reports I’ve seen

Edited June 22, 2022 by Randyw

[ThePhysicist]

1 hour ago, todd lewis said:

So as young as this vertabra reads it seams big but how large would a 15 year great white be on average?

It seems aging a shark isn't so simple. To estimate the age via ring counting, the best way is to slice the vertebra and get a thin section - some rings are not obvious. One can also more accurately age a shark using carbon found in the collagen - carbon released during nuclear bomb testing, as indicated in the paper @Troodon referenced. 

 

I was curious to see if there was a correlation between age/vertebral size/shark length, and found this paper (PDF): https://www.mass.gov/doc/contribution-51/download#:~:text=Researchers used eight sharks of,used by Hamady et al.

 

(paywalled) Hamady et al. (2014): http://dx.doi.org/10.1071/MF14127

 

The actual "rings" are probably much finer than you are perceiving:

 

Simple linear relationship of fork length ("shark length") vs vertebral radius:

 

And a growth curve, which a:

 

So, given that your vertebra has an approx radius of 40 mm, the shark it belonged to was in the ballpark of FL 450 cm (14-16 ft). 

 

The more formal definition of the vertebral radius is given by Hamady et al. (2014): "Vertebral radius is measured at the angle of the vertebra where the intermedialia meets the corpus calcareum."

 

1 hour ago, Randyw said:

Male white sharks reach sexual maturity at 3.5 to 4 metres (about 11.5 to 13 feet) in length and about 10 years of age, whereas females reach sexual maturity at 4.5 to 5 metres (about 15 to 16 feet) in length and 12 to 18 years of age

The more recent publications I could find show that maturity is later, such as that above.

[todd lewis]

i appreciate all that great data very much.  Definately credible sounding information.  Im curious how the authors of such papers conclude thier theories in to fact based published works.  Wasnt long ago shark week was sure that sharks would drowned if not continuously in motion or that they were unable to moderate there core temp forcing them to stay in more moderate temp waters.  Later a submarine recorded a large great white bumping there port hole window at apprrox. 2500 Ft.  Have anyone ever seen a baby being made or born?  Every proclaimed profesional no matter the field must stand absolute to the most recent accepted data to that field for that time but every so often wiggle in some new correct updated data?  Kinda like title practicing physician or a docs family practice?  i simply appeciate this site with you fine people and un judgingly assisting my curiosity.  Thank you so very much!

[Boesse]

On 6/22/2022 at 12:11 PM, pachy-pleuro-whatnot-odon said:

Obviously, the answer to the question has already been provided. But I just thought that, for comparison, I'd add some photographs of Otodus megalodon material that was on display at the Sauriermuseum Aathal in Switzerland back in 2018. This material comes from Aguada de Lomas in the Arequipa Department of Peru and body fossil with a very high degree of preservation, including skin remains and a full jaw of teeth.

 

 

 

The specimen on the right is almost certainly (to some degree) a fake, those vertebrae are way too small to go with the teeth.

[Troodon]

7 minutes ago, Boesse said:

The specimen on the right is almost certainly (to some degree) a fake, those vertebrae are way too small to go with the teeth.

 

Yes we had a topic on it when it first came out

 

http://www.thefossilforum.com/index.php?/topic/84197-megalodon-skeleton-from-peru/&tab=comments#comment-902875

[pachy-pleuro-whatnot-odon]

1 hour ago, Boesse said:

The specimen on the right is almost certainly (to some degree) a fake, those vertebrae are way too small to go with the teeth.

 

I had been wondering about that. When I first saw it, I couldn't believe a specimen like that existed and it did look odd. But not knowing much about sharks the specimen is rather overwhelming, especially in person, so haven't really questioned it since.

 

1 hour ago, Troodon said:

Yes we had a topic on it when it first came out

 

http://www.thefossilforum.com/index.php?/topic/84197-megalodon-skeleton-from-peru/&tab=comments#comment-902875

 

So thanks for this link...! Quite an interesting discussion and an eye-opener (I had put the small vertebrae off as being part of the tail having gotten somewhat dispersed, and hadn't spotted the discolouration of some of the teeth)

Edited June 25, 2022 by pachy-pleuro-whatnot-odon

[Coco]

Hi,

 

15 hours ago, todd lewis said:

Wasnt long ago shark week was sure that sharks would drowned if not continuously in motion

Some species have to swim continuously in order not to die, but others can remain motionless for several hours without damage, such as Orectolobus hutchinsi or Ginglymostoma (the latter can sleep during 8 hours as well).

 

A shark’s lifestyle changes depending on its genus and/or species.

 

Coco

[MJTB]

This vertebra is far too large to be from a bony fish in my opinion (3.25 inches in greatest diameter and 1.25 inches in thickness).  I believe this is a lamnoid type shark vertebra from a Great White.     

[Fin Lover]

As indicated in your other thread, your vert is not from a shark. 

[Danielb]

Bony fish vert