Suggestions for scientifically-accurate figures

[Seijun]

Air sacs on an apatosaurus? Please elaborate.

[totoro]

Aug 21, 2011 20:07:51 GMT Seijun said:

Air sacs on an apatosaurus? Please elaborate.

Vertebral pneumaticity, air sacs, and the physiology of sauropod dinosaurs

Mathew J. Wedel

Mathew J. Wedel.* Oklahoma Museum of Natural History and Department of Zoology, University of Oklahoma, Norman, Oklahoma 73072

Present address: University of California Museum of Paleontology and Department of Integrative Biology, 1101 Valley Life Sciences Building, Berkeley, California 94720-4780. [e-mail]
Abstract

The vertebrae of sauropod dinosaurs are characterized by complex architecture involving laminae, fossae, and internal chambers of various shapes and sizes. These structures are interpreted as osteological correlates of a system of air sacs and pneumatic diverticula similar to that of birds. In extant birds, diverticula of the cervical air sacs pneumatize the cervical and anterior thoracic vertebrae. Diverticula of the abdominal air sacs pneumatize the posterior thoracic vertebrae and synsacrum later in ontogeny. This ontogenetic sequence in birds parallels the evolution of vertebral pneumaticity in sauropods. In basal sauropods, only the presacral vertebrae were pneumatized, presumably by diverticula of cervical air sacs similar to those of birds. The sacrum was also pneumatized in most neosauropods, and pneumatization of the proximal caudal vertebrae was achieved independently in Diplodocidae and Titanosauria. Pneumatization of the sacral and caudal vertebrae in neosauropods may indicate the presence of abdominal air sacs. Air sacs and skeletal pneumaticity probably facilitated the evolution of extremely long necks in some sauropod lineages by overcoming respiratory dead space and reducing mass. In addition, pulmonary air sacs may have conveyed to sauropods some of the respiratory and thermoregulatory advantages enjoyed by birds, a possibility that is consistent with the observed rapid growth rates of sauropods.

www.bioone.org/doi/abs/10.1666/0094-8373%282003%29029%3C0243:VPASAT%3E2.0.CO%3B2

[Seijun]

Thanks, although I unfortunately only understood the words "the" "in" "of" and "and". Where on the Krentz apato are these "hollowed-out areas where there should be air sacs"?

[Himmapaan]

Along the top of the neck, according to Mike Taylor's blog comment (I don't know why there's a space in the word 'blog' there; I didn't include it!).

This is fascinating and entirely new to me too. Though I'm also having trouble understanding all the terms. ;D

[sfstudios]

Hey i dont want to see any of my models removed from any list!
So there! -----------lol.
I try to make them as accurate as I can and like Dan said ,the ideas and supposed new evidence changes all the time and it only takes one paleontologist to stir up the community with new ideas oh how we see the evidence so whats new is not always whats right its just another view on how to see it! thats the fun of it some things get accepted and some dont but that doesnt stop me from sculpting something i think is interesting , its just Art and my style of it with as much science in it as my little brain can cram into it. I never claim to be an authority on any thing other than model making but i take on as much knowledge as i can to help make my work look believable as possible to the fossils and the free rights we sculptors have is the outward feartures that cant be proven or disproved from the fossil evidence ,this is what makes each of us who sculpts these wonderful animals different . after all with out seeing a giraffe or horse or tiger or zebra or even a Bison, or elephants with those ears! , who would know how they looked with those distiguishing features just by seeing the bones?

[sfstudios]

Aug 22, 2011 8:16:35 GMT Seijun said:

Thanks, although I unfortunately only understood the words "the" "in" "of" and "and". Where on the Krentz apato are these "hollowed-out areas where there should be air sacs"?

If I may ,to simplify the tech talk they are saying that extinct birds showed air sacks in the neck bones and behind the hips then as Birds evolved the backbone also developed airsacks to allow lightening of the body for flight. As with sauropods the neck bones and tail bones are filled with airsacs to help lighten the animals weight as in extent birds and allowing less need for heavy muscle and allow more of the Tendons and ligiments to do the lifting of the neck which is why depecitons of Apatosaurus by many these days reflects that look in the renditions of sauropods by showing indentations between the vertabrea instead of having huge muscles covering them up! most of the Back bones had less airsacks in the weaving of the bone to allow for the support of the mass of the animal in its center of gravity which is in the sacral area and just forward of it. hope this helps.

[Seijun]

Thank you everyone, that helped a lot. I understand now!

[dinonikes]

This list is a hard thing to do- there are so many parameters that would fall within what is considered accurate- for instance on the diplo list, the Rader and Foulkes apatos look like two completely different animals- yet both would be considered accurate- so it seems like it would be easier to just keep a list of those that AREN'T accurate, ones to avoid due to real glaring flaws

[totoro]

Aug 27, 2011 18:28:32 GMT dinonikes said:

This list is a hard thing to do- there are so many parameters that would fall within what is considered accurate- for instance on the diplo list, the Rader and Foulkes apatos look like two completely different animals- yet both would be considered accurate- so it seems like it would be easier to just keep a list of those that AREN'T accurate, ones to avoid due to real glaring flaws

Well, sure seems to me like the list of inaccurate figures would be a lot longer and harder to develop. Also, for reasons already stated, a list of inaccurate figures seems more like a "worst-dressed" list, and I'm not so much seeking to cast dispersions on bad figures as create a relatively handy list of figures that have seemed to get things right. Also, a list of inaccurate figures doesn't provide collectors with a guide of where to look if you want accurate figures.

I thought it might make for some interesting discussion to call out those figures that seem most accurate based on available info - (such as the discussion just raised about Apatosaurs and air sacs.)

You're right, this leaves a lot of wiggle room, given the gaps in knowledge, but that seems fine to me. I see no problem with having two models that have different accurate interpretations of available evidence.

Finally, this isn't supposed to be a definitive list, as much as a starter list suggesting some of the available models that most accurately represent prehistoric creature. Seems like a natural fit for this forum to me.