Dinocephalian sizes

[Deleted]

Post size estimates and possible calculations about dinocephalians. Provide sources if possible.

I'm still trying to find as much papers as I can about Moschops and Tapinocephalus, I cannot provide some as of now, but some others probably can.

[creature386]

digitallibrary.amnh.org/dspace/handle/2246/1323
This paper includes lots of measurements of the single bones in Moschops. You could maybe use some of the measurements (like a 370 mm long right femur) to scale them.

[Deleted]

Sept 21, 2013 23:50:57 GMT 5 creature386 said:

digitallibrary.amnh.org/dspace/handle/2246/1323
This paper includes lots of measurements of the single bones in Moschops. You could maybe use some of the measurements (like a 370 mm long right femur) to scale them.

I already downloaded the paper. I may attempt a skeletal soon, with the help of the mounted skeleton photos.

[blaze]

That paper not only provides measurements of single bones, also of the lenght of segments of the vertebral column of the mounted skeleton, I said this in an edit to my las post on the Estemmenosuchus vs Eland thread, the mounted skeleton is ~2.7m in axial lenght, the larger specimen is around ~6% larger, approaching 3m long.

The skull of the mounted skeleton is 42cm long, that of the largest Tapinocephalus is 53cm long, assuming isometry between the two taxa, the largest Tapinocephalus is ~3.5m long.

[Deleted]

Sept 23, 2013 0:48:02 GMT 5 blaze said:

That paper not only provides measurements of single bones, also of the lenght of segments of the vertebral column of the mounted skeleton, I said this in an edit to my las post on the Estemmenosuchus vs Eland thread, the mounted skeleton is ~2.7m in axial lenght, the larger specimen is around ~6% larger, approaching 3m long.

The skull of the mounted skeleton is 42cm long, that of the largest Tapinocephalus is 53cm long, assuming isometry between the two taxa, the largest Tapinocephalus is ~3.5m long.

I know that, but what about mass? The paper has front and rear view photographs of the mounted Moschops, so a GDI may just be possible.

[creature386]

Sept 23, 2013 0:48:02 GMT 5 blaze said:

That paper not only provides measurements of single bones, also of the lenght of segments of the vertebral column of the mounted skeleton, I said this in an edit to my las post on the Estemmenosuchus vs Eland thread, the mounted skeleton is ~2.7m in axial lenght, the larger specimen is around ~6% larger, approaching 3m long.

I didn't have the tenacity for searching long, so I apologize for bad research. Thx for posting that though.

[blaze]

creature386
it's a minor thing, don´t apologize


@broly
well, yesterday I took some measurements "off-screen" of the Estemmenosuchus size chart I made a while ago, I got ~1.2m at the shoulders, ~1.5m body length and ~2.5m head body length, assuming the tail is another 50cm then it's ~3m long, as big as the biggest Moschops, eyeballing it, it doesn't seem to be more than 500kg in weight, maybe less than that, the 3.5m Tapinocephalus probably won´t be over 800kg. I could be wrong though but IMO, with this sizes I don't think weights much more over one tonne are possible.

I don't remember, the photos are perfect frontal and posterior ones? I remember that they were at an angle.

[Deleted]

Sept 23, 2013 21:15:41 GMT 5 blaze said:

@broly
well, yesterday I took some measurements "off-screen" of the Estemmenosuchus size chart I made a while ago, I got ~1.2m at the shoulders, ~1.5m body length and ~2.5m head body length, assuming the tail is another 50cm then it's ~3m long, as big as the biggest Moschops, eyeballing it, it doesn't seem to be more than 500kg in weight, maybe less than that, the 3.5m Tapinocephalus probably won´t be over 800kg. I could be wrong though but IMO, with this sizes I don't think weights much more over one tonne are possible.

I don't remember, the photos are perfect frontal and posterior ones? I remember that they were at an angle.

Well, I think it's closer to ~650 kilograms rather than ~500.



These assume that the torso width is basically the same amount as the torso depth, so that the torso volume can be calculated as 2 cylinders. I fleshed it to an amount that would be appropriate for a healthy animal.

The frontal torso section would have a volume of ~331.4 liters, while the posterior torso section would have a volume of around ~172.6 liters. Adding them together yields ~504 liters for the torso alone. Adding in the legs, neck, head, and tail, could probably get this up to ~600-700 liters. The head alone looks like it's more voluminous than the man's entire torso.

And dinocephalians aren't really known for pneumaticity. Water has a density of ~1 kilogram/liter, so we just replace liters with kilograms for mass.

[theropod]

That looks like quite a good way of roughly estimating volume.

[Deleted]

Sept 30, 2013 16:49:35 GMT 5 theropod said:

That looks like quite a good way of roughly estimating volume.

Yeah, it's a lot more time-saving than the standard GDI method, but not as precise.

The principle is finding the volume of a cylinder with differently-sized faces. Here's the formula for those who want to try:

volume = ( ? * ( ( diameter₁ / 2 ) * ( diameter₂ / 2 ) ) * length )

or

volume = ( ? * ( ( radius₁ ) * ( radius₂ ) ) * length )

[creature386]

This is not about sizes, but I have a question about Dinocephalian reconstructions. I have found this on svpow:

Dinocephalians have consistently been shown (correctly) with extended cervico-dorsal junctions and flexed cranio-cervical junctions, so those reconstructions of such things as Titanophoneus and Moschops with their necks held high and their heads at an angle are correct based on the data from living amniotes.

svpow.com/2009/06/04/necks-the-big-picture-because-there-are-other-animals-besides-sauropods/
Won't that mean Estemmenosuchus in the picture broly has shown ( i.imgur.com/8lJpWcm.png ) would have to carry it's neck more upright, like the Moschops in his (really epic) signature? Or does this apply only to Titanophoneus, Moschops and their relatives?

[Deleted]

Sept 30, 2013 17:41:09 GMT 5 creature386 said:

This is not about sizes, but I have a question about Dinocephalian reconstructions. I have found this on svpow:

Dinocephalians have consistently been shown (correctly) with extended cervico-dorsal junctions and flexed cranio-cervical junctions, so those reconstructions of such things as Titanophoneus and Moschops with their necks held high and their heads at an angle are correct based on the data from living amniotes.

svpow.com/2009/06/04/necks-the-big-picture-because-there-are-other-animals-besides-sauropods/
Won't that mean Estemmenosuchus in the picture broly has shown ( i.imgur.com/8lJpWcm.png ) would have to carry it's neck more upright, like the Moschops in his (really epic) signature? Or does this apply only to Titanophoneus, Moschops and their relatives?

Judging by the leg posture of the Estemmenosuchus, it seems to be in a walking pose, so it's good, it could be searching or stalking.

[blaze]

Or just walking, though I'm not sure but I remember reading that Moschops had vertical hindlimbs and sprawled forelimbs, that all advanced non mammalian synapdis were like that.

About the weight, Torso width equal to torso depth might be too much but that's just a "feel" completely unsubstantiated.
Anyway, if we take 650kg for that Estemmenosuchus will yield exactly 1 tonne for a 3.5m Tapinocephalus, which agrees with my original guess.

[gigadino96]

What about Titanophoneus, my favourite dinocephalian? Wikipedia said 2,85 m, but based on what? Wikipedia don't give any source at favour of this.

[creature386]

paleontologylib.ru/books/item/f00/s00/z0000001/st007.shtml

This is the best I could find. You can try to measure it.
I haven't done so, but I would guess something close to 3,4 m. The source says 3 m, but that is very likely rounded.