Spinosaurus News ~

[tigerluver]

Ibrahim et al. have just published a new study on Spinosaurus. The original 2014 specimen's tail was found. The tail is ventrally elongated, like that of newt. As such, it is a powerful swimming adaptation. The other update they have is that with this new powerful tail, Spinosaurus center of mass indicates it was bipedal if it ever came on land.

Here is the paper. In the supplement we see mass estimations.

Scroll down this page to see Spinosaurus swimming.

*This image is copyright of its original author

*This image is copyright of its original author

As I read further, there are some more changes. The weight of Spinosaurus may have increased. Take a look at this table (took it from the excel supplement and fit it into a singe image):

*This image is copyright of its original author

Spinosaurus' currently accepted weight estimates came from Henderson (2018). However, as Henderson preferred a Spinosaurus that wasn't adapted for swimming, he used a lower body density for mass estimation (3,218 kg for FSAC in the table above). Using a density closer to or greater than 1 as in swimming species, we see FSAC likely weighed at least 20% more. Consider how the bones of Spinosaurus are denser like that of penguins, FSAC likely weighed around 4,000 kg. As such, Henderson (2018) would have underestimated FSAC by 25%. 

The body length of FSAC in Ibrahim et al. (2020) is 10.37 m in natural pose and 10.93 in maximum length. The body length accepted for the largest Spinosaurus is at the lower end 15 m. Using isometry, MSNM-v4047 could be around 10-12 metric tons. Reply