Talk:Andrewsarchus

From Wikipedia, the free encyclopedia

"It was probably about 4-5 metres long, standing nearly 2 metres at the shoulder, making it the largest terrestrial carnivore that has ever existed." There were plenty of carnivorous dinosaurs that were longer than 5 metres (for example, T. Rex). Should this be "largest terrestrial carnivorous mammal" or something? --Whimemsz 21:04, May 7, 2005 (UTC)

Contents

[edit] Order?

A children's book I have (ISBN 0394837371) describes Andrewsarchus as a creodont. Of course, I'm not suggesting that outdated juvenile literature is in any way authoritative, but assuming this was the accepted understanding in 1978 rather than an isolated error, perhaps the article should mention this. Someone a little better-read in the field might provide details on what, if anything, shifted Andrewsarchus from Creodonta to Mesonychia. Lusanaherandraton 08:51, 13 November 2005 (UTC)

Andrewsarchus was not a creodont, that's sure. Your book is clearly wrong. Credonts were a sister group of the true carnivores, but Andrewsarchus was not related to them as it was an ungulate (it had hooves). It was probably not a mesonychid either, but a more primitive animal (see Mikko's Phylogeny Page).--Jyril 19:19, 13 November 2005 (UTC)
If Andrewsarchus is only known by its skull, how do we know it had hooves?
The Sanity Inspector
Because it's the skull of a mesonychid and they were hooved animals. The Singing Badger 16:00, 25 April 2006 (UTC)

Not to mention, if it is only known from one specimen, how can we say it had a "good run as a species"? Sounds like a guess to me. D Mac12:00, 28 June 2006

[edit] Discovery paper

I found the original discovery paper.[1] The paper is fairly technical, so it's not much of use for me. If there's any paleontology experts around, please take a look of it. The paper is from 1924, so the illustrations are probably in public domain. Note, however, that Andrewsarchus is probably not a mesonychid, a fact that should be mentioned in the article.--JyriL talk 13:44, 6 August 2006 (UTC)

It was originally thought to be a creodont, but recent comparisons with both creodont and mesonchyd skulls strongly suggest that it was a mesonchyd, and not a creodont as originally thought.--Mr Fink 12:48, 6 October 2006 (UTC)

[edit] Rewriting

I rewrote some of the paragraphs in the Prehistory section, and deleted others. I think that given the scarcity of A. mongoliensis fossils (a skull and some bones), it's too presumptuous to say that it was a successful species that lived throughout the Eocene. Also, I deleted the references to convergent evolution, given as how it was not immediately relevent, and that the examples given lived about 20 million years after A. mongoliensis... Like talking about the Manchus' hunting habits on an article about Shi Huangdi. That, and I eliminated references to Indricotherium.--Mr Fink 15:36, 22 September 2006 (UTC)

[edit] When?

When and exactly where did Roy Chapman Andrews discover Andrewsarchus in Mongolia? Certainly, this would be a vital piece of information.--Mr Fink 16:46, 22 November 2006 (UTC)

He didn't. Andrewsarchus was found by George Olsen.[2] I haven't found the exact year so if someone knows it, please update the article.--JyriL talk 17:13, 15 April 2007 (UTC)
According to D.R. Wallace in Beasts of Eden, the head was actually discovered by a Chinese assistant of Walter Granger's in June 1923. Iblardi 22:59, 15 April 2007 (UTC)
Well, the linked paper was from 1923 and looks like Chinese assistants didn't count back then. The assistant is apparently the Kan Chuen Pao mentioned in the infobox...--JyriL talk 10:14, 16 April 2007 (UTC)

[edit] Horses

A good way to illustrate ancient mammalian predators is to compare them with horse breeds. Since horses are quadrepedal, you can get a good idea of body size as well as the potential walking/traveling speed of the animal. The Percheron for instance weighs close to what many Andrewsarchus specimens must have weighed, and probably has a similar caloric consumption. —The preceding unsigned comment was added by 63.215.27.125 (talk) 02:28, 2 April 2007 (UTC).

This would but like comparing apples to oranges: thinking all mammalian quadrapeds are the same? We really have very little info to even guess at its body size and proportions except from its skull structure and dentition which suggests that it was more like a wolf: strong bone-crushing teeth, but was more of a scavenger than a predator. Valich 06:40, 25 October 2007 (UTC)

[edit] New Commons image

I added a 3d image of the Andrewsarchus. --Carioca 03:32, 19 April 2007 (UTC)

[edit] Exaggerations of Weight and Size

There is a habitual propensity of readers/editors to keep exaggerating the weight and size of Andrewsarchus without citing any sources, and therefore this article needs to be on a high-level watch alert. Two months ago I deleted a ridiculous addition that stated they weighed 4,000 pds. The one I feet will deleted today read "Based on the proportion comparisons to mesonychids and modern day ursids, it is believed that the largest of the Andrewsarchus weighed well over a ton, about as heavy as a Percheron horse." Does this person realize that the average Grizzly Bear or Kodiak Bear only ways about 800 pds? An ursid has a variable range of between 400-1500 pds. with only the largest "ever" recorded at 2100 pds. Similarly the average horse is only 1500 pds. In both these cases the proportions are highly dissimilar to Andrewsarchus since both an ursid and a horse are taller and you can hardly base accurate proportion comparisons to these genera based on just a skull and a few bones. Valich 10:03, 17 September 2007 (UTC)

Very good point: should we leave out size estimates of the living animal entirely, or make a very brief mention of size, or even make a brief reference to the exaggerated estimates?--Mr Fink 14:42, 17 September 2007 (UTC)
Yes, I think we should leave out size estimates altogether and I have no idea where they are coming from, except by possibly doubling the largest known weight of a brown bear. The Osborn article states that "The cranium far surpasses in size that of the Alaskan brown bear (Ursus gyas), is double Ursus gyas and treble the American wolf (Canis occidentalis)," and suggests proportions similar to Mesonyx, although even this is speculation. In any case, the skull looks much more similar to that of a wolf than a bear. Our wolf article states that "extreme specimens of more than 77 kg (170 lb) have been recorded in Alaska and Canada." If Andrewsarchus is proportional to three times that of a wolf, then its maximum weight would only have been 510 pds. I'll try to get physical descriptions of Mesonyx or other mesonychids for a better proportional weight estimate if we want to even suggest one. Valich 18:08, 18 September 2007 (UTC)
If Andrewsarchus were truly of the same proportions as a wolf but three times larger in every measurement then its volume, and therefore its mass (assuming the same average density), would be twenty-seven times that of a wolf, not three. However, Andrewsarchus was not simply a scaled-up wolf; the estimates of its length and height, based on the (reasonably safe) assumption that it was proportioned similarly to Mesonyx, show it as being twice as tall at the shoulder as a large wolf but closer to three times the length (not including the tail). Also, it should be remembered that using such a simple scaling approach is useful only for obtaining a very rough estimate of mass.
I find the estimate of 250 kg ("one quarter of a metric ton") very hard to believe. This weight is rather less than that of an adult male Red Deer, which for a creature that was roughly as tall as a racehorse and quite a bit longer seems ludicrous. This would make it far leaner than a cheetah or greyhound - positively gaunt, in fact. I am still waiting to get my hands on a copy of the DVD to check the reference - and won't make any changes to the article until I have checked it - but I will note that there exists a formula that relates the approximate mass of a mesonychid to the size of its teeth which gives a mass estimate of 1250 kg for Andrewsarchus, or one and a quarter metric tons.
One thing that definitely needs changing regarding the measurements given in the article is the units used. The continuous jumping between metric and non-metric units is very confusing. —Preceding unsigned comment added by Morcar (talk • contribs) 01:22, 27 November 2007 (UTC)
(sorry, forgot to sign my comment)Morcar (talk) 01:29, 27 November 2007 (UTC)
Correction: re-reading what I wrote last night set a couple of alarm bells going. I'm not sure about 250 kg being less than the weight of a Red Deer - I got this from the Red Deer article, whereas most of the other resources I can find put its weight at about 190 kg at the most. It's possible that the Red deer article knows of larger subspecies than the local ones I'm used to, or it could point to confusion with the larger Elk, which used to be considered the same species. Either way, I still think 250 kg sound far too little for Andrewsarchus. Morcar (talk) 11:13, 27 November 2007 (UTC)

[edit] Who is Kan Chuen Pao?

Was he a Chinese paleontologist?--Mr Fink 14:40, 18 September 2007 (UTC)

He was a member of the third Asiatic expedition led by Andrews. Reference to Kan Chuen Pao is also in the Polish and Finnish Wikipedia articles. Valich 18:11, 18 September 2007 (UTC)
We should start an article about him, too, then.--Mr Fink 23:31, 18 September 2007 (UTC)

[edit] Image copyright issue

Andrewsarchus10.jpg has been deleted as a copyright violation JodyB talk 03:19, 20 November 2007 (UTC)

[edit] Brown Bears

If well fed brown bears in zoos can get over a ton, and this is documented, it is doubtful that Andresarchus could not easily weigh a ton or more. —Preceding unsigned comment added by Mtloweman (talk • contribs) 05:12, 19 February 2008 (UTC)