Andrewsarchus?

[TyrannosaurusRex]

My question is, what exactly was Andrewsarchus? I find the artwork of it to be absolutely fascinating. What all do yall know about it?

Personally I like to think of it as a massive wolf-like creature, but I've also heard it go as a ungulate.

[Auspex]

I think it has fairly strong affinities with the Entelodonts, but with the lack of skeletal material, who can say for sure?

[Pterosaur]

It is known only from a meter-long, partial skull (the upper jaw) that was found back in 1923 in the Gobi Desert, and is classified as an Artiodactyl (even-toed ungulate). Interestingly, it has been put in the Cetruminantia clade of which ruminantia and whippomorpha are members. Andrewsarchus is suspected to fall under the whippomorpha sub-group; which contains hippopotamuses and cetacea (whales, dolphins, porpoises). It was originally classified in the clade, Mesonychia, based on similar teeth and skull structure to other mesonychid species. However, recent studies have shown it to be more closely related to entelodonts and probably kin to Whippomorpha.

I've always thought Andrewsarchus was pretty neat. I have a feeling it looked WAY different than what illustrations depict, but really I have no idea. It's pretty amazing that it is suspected to be connected with hippopotamus and cetacea....

Here's a couple paragraphs from Wikipedia about Andrewsarchus:

"The appearance and behavioral patterns of Andrewsarchus are virtually unknown and have been topics of debate among paleontologists ever since it was first discovered. All that is known about Andrewsarchus comes chiefly from the single meter-long skull found in Late Eocene sediments in what is now Mongolia.

The skull of Andrewsarchus, compared to other carnivore skulls. Note the front teeth useful for piercing but the teeth further back in the jaw are large and blunted

New theories indicate that the teeth of Andrewsarchus may have been blunt and uncharacteristic of predators. Its diet could have been more omnivorous than carnivorous, consisting ofcarrion, bones, rooted plants, or mollusks rather than freshly killed meat. As a scavenger, Andrewsarchus may have gained access to freshly killed carcasses by using its formidable size to scare away other smaller predators and scavengers. Until more fossil evidence that may provide insight into these areas of uncertainty is uncovered any reconstructions remain highly speculative.

Andrewsarchus possessed some of the strongest jaws ever seen in a land mammal, able to bite through large bones if needed. To judge from its immense jaws, and the coastal location of the fossils, Andrewsarchus may have fed on beached primitive whales, shellfish and hard-shelled turtles, and contemporary large mammals at various periods during its existence. Toward the end of the Eocene very large mammals (such as the brontotheres) had evolved in the region of Central Asia.

Despite the enormous jaws and very sturdy teeth, Andrewsarchus did not have teeth adapted for the carnassial shear. Judging by its size, the animal most likely fed on large animals such as the extinct brontotheres, which were among the largest herbivorous mammals at the time, possibly both hunting them, and scavenging already dead carcasses. If plant material was also eaten, Andrewsarchus would have had a lifestyle similar toentelodonts. "

Wikipedia contributors. "Mesonychid." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 14 Aug. 2015. Web. 19 Aug. 2015.

[TyrannosaurusRex]

It is known only from a meter-long, partial skull (the upper jaw) that was found back in 1923 in the Gobi Desert, and is classified as an Artiodactyl (even-toed ungulate). Interestingly, it has been put in the Cetruminantia clade of which ruminantia and whippomorpha are members. Andrewsarchus is suspected to fall under the whippomorpha sub-group; which contains hippopotamuses and cetacea (whales, dolphins, porpoises). It was originally classified in the clade, Mesonychia, based on similar teeth and skull structure to other mesonychid species. However, recent studies have shown it to be more closely related to entelodonts and probably kin to Whippomorpha.

I've always thought Andrewsarchus was pretty neat. I have a feeling it looked WAY different than what illustrations depict, but really I have no idea. It's pretty amazing that it is suspected to be connected with hippopotamus and cetacea....

Here's a couple paragraphs from Wikipedia about Andrewsarchus:

"The appearance and behavioral patterns of Andrewsarchus are virtually unknown and have been topics of debate among paleontologists ever since it was first discovered. All that is known about Andrewsarchus comes chiefly from the single meter-long skull found in Late Eocene sediments in what is now Mongolia.

The skull of Andrewsarchus, compared to other carnivore skulls. Note the front teeth useful for piercing but the teeth further back in the jaw are large and blunted

New theories indicate that the teeth of Andrewsarchus may have been blunt and uncharacteristic of predators. Its diet could have been more omnivorous than carnivorous, consisting ofcarrion, bones, rooted plants, or mollusks rather than freshly killed meat. As a scavenger, Andrewsarchus may have gained access to freshly killed carcasses by using its formidable size to scare away other smaller predators and scavengers. Until more fossil evidence that may provide insight into these areas of uncertainty is uncovered any reconstructions remain highly speculative.

Andrewsarchus possessed some of the strongest jaws ever seen in a land mammal, able to bite through large bones if needed. To judge from its immense jaws, and the coastal location of the fossils, Andrewsarchus may have fed on beached primitive whales, shellfish and hard-shelled turtles, and contemporary large mammals at various periods during its existence. Toward the end of the Eocene very large mammals (such as the brontotheres) had evolved in the region of Central Asia.

Despite the enormous jaws and very sturdy teeth, Andrewsarchus did not have teeth adapted for the carnassial shear. Judging by its size, the animal most likely fed on large animals such as the extinct brontotheres, which were among the largest herbivorous mammals at the time, possibly both hunting them, and scavenging already dead carcasses. If plant material was also eaten, Andrewsarchus would have had a lifestyle similar toentelodonts. "

Wikipedia contributors. "Mesonychid." Wikipedia, The Free Encyclopedia. Wikipedia, The Free Encyclopedia, 14 Aug. 2015. Web. 19 Aug. 2015.

Very fascinating. I prefer thinking of it as the large, carnivorous predator, (imagination plays a large role in this ) But I am wondering, rather that Enteledont, is is perhaps more closely related to the Pachyaena Ossifraga, Mesonyx Uintensis and the Symplotheium Vorax? It has an incredible similarity in the bone structure of the skull, especially the cranium. The teeth are different, however. It makes an interesting thought. Andrewsarchus is one of my favorite creatures to ever walk the earth. It's a 2 ton monster! Who wouldnt like it? (Perhaps the person being eaten by it haha?)

[jpc]

Wikipedia should always be taken with a grain of salt, and the actual sources checked. Try this... do a Google Scholar search for Andewsarchus.

[Doctor Mud]

Wikipedia should always be taken with a grain of salt, and the actual sources checked. Try this... do a Google Scholar search for Andewsarchus.

Good point JPC. Although there is the perception that Wikipedia is more reliable than other sources on the net it hasn't passed a strict peer review by scientists who are specialists in the field.

A Google scholar search will link you to studies that have. Only downside is that articles are not always available free but contacting authors is a good way to get a free copy of a paper. Most people respond well to someone wanting to read their paper - don't be shy :-)

Edited August 20, 2015 by Doctor Mud

[LordTrilobite]

There's a lifesize reconstruction in the museum Museon in The Hague, Netherlands. It's quite nice. Also huge.

[Pterosaur]

Good point JPC. Although there is the perception that Wikipedia is more reliable than other sources on the net it hasn't passed a strict peer review by scientists who are specialists in the field.

A Google scholar search will link you to studies that have. Only downside is that articles are not always available free but contacting authors is a good way to get a free copy of a paper. Most people respond well to someone wanting to read their paper - don't be shy :-)

Never thought of this, but excellent advice.

[TyrannosaurusRex]

Good point JPC. Although there is the perception that Wikipedia is more reliable than other sources on the net it hasn't passed a strict peer review by scientists who are specialists in the field.

A Google scholar search will link you to studies that have. Only downside is that articles are not always available free but contacting authors is a good way to get a free copy of a paper. Most people respond well to someone wanting to read their paper - don't be shy :-)

I definitely will try this. Thanks for the advice!

[Ridgehiker]

Good point JPC. Although there is the perception that Wikipedia is more reliable than other sources on the net it hasn't passed a strict peer review by scientists who are specialists in the field.

A Google scholar search will link you to studies that have. Only downside is that articles are not always available free but contacting authors is a good way to get a free copy of a paper. Most people respond well to someone wanting to read their paper - don't be shy :-)

Good point JPC. Although there is the perception that Wikipedia is more reliable than other sources on the net it hasn't passed a strict peer review by scientists who are specialists in the field.

A Google scholar search will link you to studies that have. Only downside is that articles are not always available free but contacting authors is a good way to get a free copy of a paper. Most people respond well to someone wanting to read their paper - don't be shy :-)

So true about the papers. In the pre digital age if receiving an inquiring letter from a keener, the author would often send out the whole publication that contained the article...with a letter, etc. Researchers are usually enthused about their subject. It's always best to ask some specific question with the request to show that you also have some enthusiasm.

An aside...what a 'blah' name for such a mean looking critter. Osborne deserves a gold medal for coming up with the name 'Tyrannosaurus rex'. What if he had named it after the finder: 'Brownosaurus'. Just wouldn't have the cultural prominence. Always adds some zip to fossils to have names like T. Rex, Velociraptor, Megalodont, Ttanothere, etc.

[siteseer]

JP, Doctor Mud, everyone

I agree that Wikipedia is something less than reliable when looking for answers to questions about science. It's great for looking back at the history of the Doobie Brothers but I wouldn't quote it when tracing the ancestry of any particular group of organisms. Some pages are better than others but the newbie researcher is always better off looking for the original journal articles or books by the authors of those articles. You always want to know what was actually said rather than the interpretation of a Wikipedia editor who passed no test nor interview to qualify for adding or changing Wikipedia content.

The value of Wikipedia is often in the reference list for each subject. You can double-check what is said in the paragraphs.

You can't expect information to be free. If fact, as in the case of Wikipedia, I have learned to be wary of free information. Most of the articles and books that have ever been written about paleontology have yet to be uploaded to the web though there is that perception that everything is out there now. Usually, you have to hunt down an article in an actual library and photocopy/scan it yourself. Most of the articles I have were either photocopied by me or they came from friends who copied them. A few years ago, I started a pdf collection as well.

Jess

Good point JPC. Although there is the perception that Wikipedia is more reliable than other sources on the net it hasn't passed a strict peer review by scientists who are specialists in the field.

A Google scholar search will link you to studies that have. Only downside is that articles are not always available free but contacting authors is a good way to get a free copy of a paper. Most people respond well to someone wanting to read their paper - don't be shy :-)