# Antartican organisms (extinct) **URL:** \ **Category:** Factual Questions\ **Created:** [June 19, 2012, 10:17pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686 "2012-06-19T22:17:38Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![griffon502](https://avatars.discourse-cdn.com/v4/letter/g/cdc98d/32.png) [@griffon502](https://boards.straightdope.com/u/griffon502)\ **Post date:** [June 21, 2012, 5:58am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/21 "2012-06-21T05:58:04Z")
> [@Colibri](#): > > That last comment [in post #17] is incorrect. You can’t consider that there are 7 independent “experiments,” but as **Blake** says, only three. Europe/Asia/Africa/North America have been effectively one land mass for most of the Cenozoic (the “World Continent”, while Australia and South America were isolated island continents. Placentals dominated the World Continent, marsupials Australia, and South America had marsupial carnivores and placental herbivores. (We don’t know much about Antarctica.) > > If there is a competitive advantage, it is between animals that have evolved on larger land masses have an advantage over those from smaller landmasses. If animals from the World Continent have an advantage over those from the island continents, it’s likely due to the fact that they come from a larger land mass. You fail to identify any mechanism. It is obvious when you compare animal to animal. I’ve already illustrated the numbat example pretty well. And I also pointed out how ruminants are more efficient than kangaroos. Your larger landmass point is without evidence, and pure speculation. ---
**Author:** ![Mewl\_Dear](https://avatars.discourse-cdn.com/v4/letter/m/d6d6ee/32.png) [@Mewl\_Dear](https://boards.straightdope.com/u/Mewl_Dear)\ **Post date:** [June 21, 2012, 6:40am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/22 "2012-06-21T06:40:54Z")
> [@Kamrusepas](#): > > Looks like I’ll have to be the first to say the obvious: > > Great Old Ones. > [URL=“[Cthulhu Mythos deities - Wikipedia](http://en.wikipedia.org/wiki/Great_Old_Ones)”] What does this even mean. Nevermind if you can add nothing, stay out and I will too. ---
**Author:** ![griffon502](https://avatars.discourse-cdn.com/v4/letter/g/cdc98d/32.png) [@griffon502](https://boards.straightdope.com/u/griffon502)\ **Post date:** [June 21, 2012, 9:25am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/23 "2012-06-21T09:25:43Z")
I just thought of something new, related to what Blake said. Blake and his marxist-eco professors or whatever, claim that placental animals somehow “wastes” more energy than marsupials. First, I am not sure about the validity of that claim. Modern ecologists, influenced by marxists, do everything to demonize so-called “non-native” species. Second, is what I am trying to present now. That is, they are ignorant of what energy is. If these so-called “ecologists” actually understand the physics taught during highschool, they might not be quick to invent such myth as “wasting energy”. Why? Because basic physics tells us, energy never disappear. They merely transform into another form. Assuming the claim that placentals somehow consume more energy than marsupials, it simply means they are more efficient energy users. Almost all energy of an organism ultimately comes from the sun. When the sun shines, the plants convert solar energy into chemical energy via photosynthesis. Then they are eaten by herbivores which consumes its own chemical energy to obtain more chemical energy from plant matters, and they are in turn eaten by carnivores who spend chemical energy in pursuit of more chemical energy from the meat of the herbivores. Therefore, energy is always there to take, but taking them require energy itself, so different organisms spend different amount of energy in order to obtain more energy. For instance, areptiles have low energy requirement compared to . They are cold-blooded (i.e. do not need energy-expensive thermoregulation), so they can require less energy to survive because their energy expenture is low. A nile crocodile can survive months without food while a lion would turned into a skeleton already. But this is done at a cost. Though reptiles do not need expensive thermoregulation, it also means they are less adaptable at colder climates than mammals. Mammals can survive in the arctic by converting chemical energy into heat energy, aided by thick coat or fat. Reptiles just freeze to death. Therefore whether a species is more “advanced” might be indicated by the level of energy it could utilize. Humans, for example, have become the master of energy, to a level not a single other species of organism have ever achieved. And within human itself such distinction is still valid. More advanced people are able to utilize more energy than the less advanced. While people in the civilized world are able to obtain chemical energy from food in a large scale cheaply, exploiting energy from sources such as electricity, and even “wasting” massive energy by burning them in a few seconds in rocket-fuels for some of the fortunate ones for space tourism, the less advanced still rely on charcoals and have to spend their own energy just to carry water from the rivers because there is no running water. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [June 21, 2012, 9:34am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/24 "2012-06-21T09:34:09Z")
> [@Kamrusepas](#): > > Looks like I’ll have to be the first to say the obvious: > > Great Old Ones. > [ I think you mean [URL=“[Elder Thing - Wikipedia](http://en.wikipedia.org/wiki/Elder_Thing)”]Elder Things]([Cthulhu Mythos deities - Wikipedia](http://en.wikipedia.org/wiki/Great_Old_Ones)) ---
**Author:** ![Frodo](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/frodo/32/302_2.png) [@Frodo](https://boards.straightdope.com/u/Frodo)\ **Post date:** [June 21, 2012, 1:45pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/25 "2012-06-21T13:45:32Z")
Tekeli-li! Tekeli-li! ---
**Author:** ![Polycarp](https://avatars.discourse-cdn.com/v4/letter/p/82dd89/32.png) [@Polycarp](https://boards.straightdope.com/u/Polycarp)\ **Post date:** [June 21, 2012, 1:59pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/26 "2012-06-21T13:59:17Z")
> [@Mewl\_Dear](#): > > What does this even mean. > Nevermind if you can add nothing, stay out and I will too. The Great Old Ones were the malign Elder Gods who, among other things, inhabited Antarctica in Days Of Yore (and Gore and Vore) in the Chulhu Mythos of H.P. Lovecraft and his circle of horror writers. It was in the nature of a recondite witticism. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [June 21, 2012, 2:12pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/27 "2012-06-21T14:12:51Z")
> [@griffon502](#): > > You fail to identify any mechanism. This is a fairly well known hypothesis. The mechanism is that animals on larger land masses are confronted by competition from a larger number of species, and thus have their competitive capacity honed. [Here’s some detailed discussion of the hypothesis.](http://www.dalecozort.com/AHNewsletter/June02/alternategeology.htm) > [@](#): > > It is obvious when you compare animal to animal. I’ve already illustrated the numbat example pretty well. And I also pointed out how ruminants are more efficient than kangaroos. No, it’s not particularly obvious. Cherry-picking examples is not evidence. > [@](#): > > Your larger landmass point is without evidence, and pure speculation. There’s as much evidence for it as your speculation. ---
**Author:** ![griffon502](https://avatars.discourse-cdn.com/v4/letter/g/cdc98d/32.png) [@griffon502](https://boards.straightdope.com/u/griffon502)\ **Post date:** [June 21, 2012, 2:50pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/28 "2012-06-21T14:50:30Z")
> [@Colibri](#): > > This is a fairly well known hypothesis. The mechanism is that animals on larger land masses are confronted by competition from a larger number of species, and thus have their competitive capacity honed. > > [Here’s some detailed discussion of the hypothesis.](http://www.dalecozort.com/AHNewsletter/June02/alternategeology.htm) > > No, it’s not particularly obvious. Cherry-picking examples is not evidence. > > There’s as much evidence for it as your speculation. How’s that cherry-picking? Seems to me you are ignoring the overwelming evidence. And for the theory, I know it very well. However you applied it wrong, which is why you came to the wrong conclusion. ---
**Author:** ![Filbert](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/filbert/32/3433_2.png) [@Filbert](https://boards.straightdope.com/u/Filbert)\ **Post date:** [June 21, 2012, 3:58pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/29 "2012-06-21T15:58:37Z")
Cane toads are a major pest in Australia, so I take it this means anurans are superior lifeforms as well? What introduced species do well is really not an indicator of some imagined subclass superiority- hell, New Zealand Flatworms are becoming a serious problem in the UK, and they’re _flatworms_. All it can possibly mean is that that single species has found a niche where it is, at least in the short term, outcompeting one or more native species, which can take place for a variety of reasons, including being more adapted to the environmental change being brought about by humans. If every time a new group came along it wiped out the previous donimant group, we wouldn’t still have birds, reptiles, amphibians, insects… Oh, and for someone who claims to be only concerned with the facts, comments like: > [@griffon502](#): > > Shame that the placentals never made it to Australia before the human influence except some bats. Just a single semi-domesticted dog (dingo) caused mass extinction of marsupials, and made the Tasmanian tigers extinct on mainland, that’s just an example on how inefficient the marsupials are when it comes to best-utilize the available resources. don’t half make it sound like you have some odd personal grudge against marsupials. Ever considered campaigning against monotremes instead? ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [June 21, 2012, 10:30pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/30 "2012-06-21T22:30:51Z")
> [@griffon502](#): > > How’s that cherry-picking? Seems to me you are ignoring the overwelming evidence. You haven’t presented any overwhelming evidence. You’ve presented a couple of examples. That’s cherry-picking. > [@](#): > > And for the theory, I know it very well. If you had heard of it, then why did you ask me to identify the mechanism? > [@](#): > > However you applied it wrong, which is why you came to the wrong conclusion. Whatever are you talking about? Please explain how I applied it wrong. And how do you know your conclusion is right and mine is wrong, exactly? ---
**Author:** ![griffon502](https://avatars.discourse-cdn.com/v4/letter/g/cdc98d/32.png) [@griffon502](https://boards.straightdope.com/u/griffon502)\ **Post date:** [June 22, 2012, 12:03am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/31 "2012-06-22T00:03:20Z")
Just found more evidence of the inefficiency of the marsupials It turned out that the top apex predator of marsupials in modern times, the tasmanian tiger, was totally incompetent, compared to placental equivalents. From wiki: “A 2011 study by the University of New South Wales using advanced computer modelling indicated that the **thylacine had surprisingly feeble jaws**. Animals usually take prey close to their own body size, but an adult thylacine of around 30 kilograms (66 lb) was found to be **incapable of handling prey much larger than 5 kilograms** (11 lb). Researchers believe thylacines **only ate small animals such as bandicoots and possums** , putting them into direct competition with the Tasmanian devil and the Tiger Quoll. Such specialisation probably made the thylacine susceptible to small disturbances to the ecosystem.[31][53]” I mean seriously, how pathetic, a marsupial as large as the wolf, can only handle such small preys. NOW THIS _IS_ inefficiency, or even inferiority, compared to placentals. You simply cannot deny it. ---
**Author:** ![Oldeb](https://avatars.discourse-cdn.com/v4/letter/o/ea666f/32.png) [@Oldeb](https://boards.straightdope.com/u/Oldeb)\ **Post date:** [June 22, 2012, 3:35am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/32 "2012-06-22T03:35:49Z")
> [@griffon502](#): > > I mean seriously, how pathetic, a marsupial as large as the wolf, can only handle such small preys. NOW THIS _IS_ inefficiency, or even inferiority, compared to placentals. You simply cannot deny it. I don’t understand how you’re defining inefficiency. Predator/Prey size relationship seems an extremely bizarre definition. By that token the baleen whales (which include nine of the ten largest mammals) are vastly inferior to anything that has ever lived. For terrestrial mammals the Giant Anteater grows to more than twice the size of the Thylacine (up to 7 ft and 140 pounds) yet eats only insects as it lacks teeth. Does that make it horrible as well? It sounds like existing on a diet of smaller than expected prey would relate first to **Blake** ’s point about metabolic efficiency being greater in marsupials and then to **Colbri** ’s point about specialization and lack of competition leading to animals that fair poorly when introduced to new species. ---
**Author:** ![Colibri](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/colibri/32/1841_2.png) [@Colibri](https://boards.straightdope.com/u/Colibri)\ **Post date:** [June 22, 2012, 3:40am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/33 "2012-06-22T03:40:00Z")
> [@griffon502](#): > > I mean seriously, how pathetic, a marsupial as large as the wolf, can only handle such small preys. NOW THIS _IS_ inefficiency, or even inferiority, compared to placentals. You simply cannot deny it. On the other hand, according to Wiki the recently extinct [_Thylacoleo_](http://en.wikipedia.org/wiki/Thylacoleo) was the most remarkable mammalian carnivore of all time: > [@](#): > > Pound for pound, Thylacoleo carnifex had the strongest bite of any mammal species living or extinct; a 100 kg (220 lb) T. carnifex had a bite comparable to that of a 250 kg (550 lb) African Lion[1] and is thought to have hunted large animals such as Diprotodon spp. and giant kangaroos. It also had extremely strong forelimbs, with retractable catlike claws, a trait previously unseen in marsupials. Thylacoleo also possessed enormous hooded claws set on large semi-opposable thumbs, which were used to capture and disembowel prey. The long muscular tail was similar to that of a kangaroo. Specialized tail bones called chevrons allowed the animal to tripod itself, and freed the front legs for slashing and grasping.[2] > Its strong forelimbs, retracting claws and incredibly powerful jaws mean that it may have been possible for Thylacoleo to climb trees and perhaps to carry carcasses to keep the kill for itself (similar to the leopard today). Due to its unique predatory morphology, scientists repeatedly claim Thylacoleo to be the most specialized mammalian carnivore of all time.[3] By your own criteria, this means that marsupials must be superior to placentals.😉 Note that the _Thylacoleo_ probably became extinct due to the arrival of humans in Australia, not because of any competition with placentals. ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [June 22, 2012, 3:53am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/34 "2012-06-22T03:53:25Z")
So back to the OP. is it still the case that no true mammal fossils have been found in Antarctica? So far both Marsupial and proto-mammalian fossils have been found but no modern mammals? Is that correct? ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [June 22, 2012, 6:02pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/35 "2012-06-22T18:02:19Z")
> [@Colibri](#): > > Note that the _Thylacoleo_ probably became extinct due to the arrival of humans in Australia, not because of any competition with placentals. Nitpick: aren’t humans placental? 😉 ---
**Author:** ![Sailboat](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/sailboat/32/461_2.png) [@Sailboat](https://boards.straightdope.com/u/Sailboat)\ **Post date:** [June 22, 2012, 6:03pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/36 "2012-06-22T18:03:43Z")
> [@griffon502](#): > > I mean seriously, how pathetic, a marsupial as large as the wolf, can only handle such small preys. NOW THIS _IS_ inefficiency, or even inferiority, compared to placentals. You simply cannot deny it. Why the terminology of value judgment? What’s “pathetic” about an animal’s diet? ---
**Author:** ![DrDeth](https://avatars.discourse-cdn.com/v4/letter/d/b487fb/32.png) [@DrDeth](https://boards.straightdope.com/u/DrDeth)\ **Post date:** [June 23, 2012, 1:46am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/37 "2012-06-23T01:46:18Z")
> [@Blake](#): > > In the real world we have three natural experiments: Australia, South America./Antarctica and the rest of the planet. In Australia marsupials dominated and placentals became completely extinct extinct. In south America, marsupials completely dominated the carnivore/omnivore niches and placentals were restricted to herbivory. In the rest of the world placentals became completely extinct. I think you meant to say “In the rest of the world \*marsupials \*became completely extinct.” Other than that, I agree with you nearly 100%. ---
**Author:** ![griffon502](https://avatars.discourse-cdn.com/v4/letter/g/cdc98d/32.png) [@griffon502](https://boards.straightdope.com/u/griffon502)\ **Post date:** [June 23, 2012, 1:55am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/38 "2012-06-23T01:55:26Z")
More evidence supporting my theory that the relatively success of South American terror birds before the Great American Exchange, was due to the inefficiency of the marsupials. from wiki: > [@](#): > > Metatherians were the only South American mammals to specialize as carnivores; their relative inefficiency created openings for nonmammalian predators to play more prominent roles than usual (similar to the situation in Australia). > **[Great American Interchange](https://en.wikipedia.org/wiki/Great_American_Interchange)** > > The Great American Biotic Interchange (commonly abbreviated as GABI), also known as the Great American Interchange and the Great American Faunal Interchange, was an important late Cenozoic paleozoogeographic biotic interchange event in which land and freshwater fauna migrated from North America to South America via Central America and vice versa, as the volcanic Isthmus of Panama rose up from the sea floor, forming a land bridge between the previously separated continents. Although earlier disper... Note the Metatherians had been regarded as marsupials, but recently it has been seperated from it but still regarded as being very closely related. Also note that it was the only carnivorous mammal in SA before the arrival of the placental carnivores with the Great Amercan Exchange, meaning the metatherians out-competed the marsupials yet got defeated by the placentals. ---
**Author:** ![MrDibble](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mrdibble/32/114_2.png) [@MrDibble](https://boards.straightdope.com/u/MrDibble)\ **Post date:** [June 23, 2012, 1:27pm UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/39 "2012-06-23T13:27:18Z")
Dude, let it go. ---
**Author:** ![griffon502](https://avatars.discourse-cdn.com/v4/letter/g/cdc98d/32.png) [@griffon502](https://boards.straightdope.com/u/griffon502)\ **Post date:** [June 28, 2012, 4:22am UTC](https://boards.straightdope.com/t/antartican-organisms-extinct/625686/40 "2012-06-28T04:22:04Z")
This slide below just freaking NAILED IT. Marsupials _are_ inferior. They deserve to be replaced by placentals. Australia should stop its overly-protective policies. Heck, you can’t even own a freaking HAMSTER because it is feared that these “foreign” animals would “devastate” the marsupials. LOL. Bring it on. No mercy for the losers. You don’t deserve tears when you lose the evolutionary race. [http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=2&ved=0CEwQFjAB&url=http%3A%2F%2Fplanet.botany.uwc.ac.za%2FNISL%2FGwen’s%2520Files%2FBiodiversity%2FEvolution%2520of%2520Biodiversity%2Flecture8.ppt&ei=X9frT8nlG-2QiAfmpaXEBQ&usg=AFQjCNF0k2acSTBoNPAkVI7O5W1QShFF\_Q](http://www.google.com/url?sa=t&rct=j&q=&esrc=s&frm=1&source=web&cd=2&ved=0CEwQFjAB&url=http%3A%2F%2Fplanet.botany.uwc.ac.za%2FNISL%2FGwen's%2520Files%2FBiodiversity%2FEvolution%2520of%2520Biodiversity%2Flecture8.ppt&ei=X9frT8nlG-2QiAfmpaXEBQ&usg=AFQjCNF0k2acSTBoNPAkVI7O5W1QShFF_Q) Some important parts in the slide: II. Are marsupials inferior? A. Lines of reasoning that they are: 1. Less diversity of habitat types 2. Less diversity of locomotion 3. Less diversity of foraging 4. No really big marsupials 5. Social organization is less complex 6. Not as speciose 7. Most diverse and numerous in Australia, where there is negligible competition with eutherians B. Is the competitive disadvantage the result of their mode of reproduction? Maybe. Their mode of reproduction limits the environments in which they can live. Maybe not. Other factors include: Cerebral cortex of marsupials is smaller and develops more slowly Learning and behavioral flexibility is less developed in marsupials. Behavior is less diverse. They have a small number of chromosomes, which may make them less evolutionarily flexible. Their reproductive rate is lower. C. An alternate view is that marsupials are not necessarily at a competitive disadvantage in all circumstances. Possible advantages of a marsupial reproductive stratgey include: Low energy requirements, spread out of a long period of time Can quickly replace lost young [Previous page](https://boards.straightdope.com/t/antartican-organisms-extinct/625686.md?page=1) [Next page](https://boards.straightdope.com/t/antartican-organisms-extinct/625686.md?page=3)