Extinction Peeve

[WildCat]

The saber tooths are gone too.

No they're not, just look at my avatar!

 

[Hexxenhammer]

Bison aren't extinct. I'm not sure even hundreds of Mammoths would be killed if cornered. It would be a horrible waste of meat. Noone can butcher hundreds of mammoths before they rot.

Big, giant, prehistoric bison (bison antiquus) are extinct, of course bison bison are still around.

 

[WildCat]

Mammoth went extinct in Asia at the same time, where they had existed w/ humans for thousands of years. And they survived the end of previous ice ages. I think it was more likely some sort of virus or other disease that did them in, though I don't have any evidence to support this.

 

[richardm]

I'm not sure even hundreds of Mammoths would be killed if cornered. It would be a horrible waste of meat. Noone can butcher hundreds of mammoths before they rot.

No, but why would you (as a prehistoric hunter) care about that? All that would matter would be that you had enough to feed you and the rest of your group. After all, there are plenty of mammoths about the place, no need to fuss about a few leftovers.

If the easy way to kill mammoth is to herd them into a corner and then spear them from above, you'd do that, surely?

 

[a_unique_person]

I agree that the humans may have been a factor, but when you read about 'animals innocent of man' it just makes me wonder, why are the elephants still in Asia and Africa, I am willing to believe that modern humans with rifles can extinct a species but why only here in North America for the large megafauna, thanks all, I am trying to open my mind.

IIRC there was not a large human population in the savannah area where the mega fauna live. It is pretty harsh living, alternating between droughts and floods.

In Asia, the elephant was domesticated. There was also not a big emphasis on meat eating.

The placental's may have taken over from the mammals on the rest of the earth, but in Australia, many have adapted in ways that give them an edge in some ways. For example, the kangaroo hopping is the most efficient form of foot transport. The platypus has evolved a 'sixth sense' to detect it's food by the electrical output using it's bill.

England had many animals such as bears, etc. They all went long ago, purely due to hunting.

 

[Dancing David]

IIRC there was not a large human population in the savannah area where the mega fauna live. It is pretty harsh living, alternating between droughts and floods.

In Asia, the elephant was domesticated. There was also not a big emphasis on meat eating.

The placental's may have taken over from the mammals on the rest of the earth, but in Australia, many have adapted in ways that give them an edge in some ways. For example, the kangaroo hopping is the most efficient form of foot transport. The platypus has evolved a 'sixth sense' to detect it's food by the electrical output using it's bill.

England had many animals such as bears, etc. They all went long ago, purely due to hunting.

Hm, England was under the ice sheet for most of the last ice age, except for the south where you could walk to france.

There is also the thing about homo sap burning the forsts.

More man involved extinction.

 

[arcticpenguin]

When species get outside their natural range, they can proliferate as they didn't in their home range. We all know the examples: rabbits in Australia, kudzu in the SE USA, 'killer bees', brown tree snakes in Hawaii and other islands.

Maybe man left behind the natural checks on his population when he left Africa (malaria and other diseases? man-eating predators?)

 

[Dancing David]

Mountainn lions are very big! They find humans quite tasty.

But I agree that humans may have had a small role in the extinction of the North American mega fauna.

 

[arcticpenguin]

True, mountain lions are big enough and do sometimes kill people, but they don't hunt in packs the way African lions do.

 

[Correa Neto]

There are several points that must be considered. The first one is that quit often in natural sciences, when there are two different lines of reasoning, the truth is something between both of them. Many specialists nowdays agree that there was an anthropic component to these extinctions, as well as an envitonmental.

Wich one predominated? Each species had its own characteristics and "vulnerabilities", so its quite likely that each extincted species should be treated differently. North America megafauna was different from that of South America, and paleoindians populations in these continents had different survival strategies. Basically in North America they were hunters of big game, while here in South America, generalistic and oportunistic hunter-gatherers. Therefore the same reasoning can not be used for both continents and for every megafauna species.

One has to be carefull when comparing bisons with mammoths or mastodons. The population of big species with large gestation time and whose offspring take long times to reach sexual maturity (like elephants - OK, we are guessing that they were similar with living elephants) will suffer a greater impact once a new predator is introducted in the environment. In this case, even a small increase in the killing rate may, after some time dictate a large population decrease. This may be one of the reasons why there are still bisons in North America, but no more mastodonts

 

[Eos of the Eons]

No, but why would you (as a prehistoric hunter) care about that? All that would matter would be that you had enough to feed you and the rest of your group. After all, there are plenty of mammoths about the place, no need to fuss about a few leftovers.

If the easy way to kill mammoth is to herd them into a corner and then spear them from above, you'd do that, surely?

That goes against North American Indian ways of life. They respected nature and tried to avoid waste. Spear a few, let the rest go, you know. Unless someone has proof otherwise.

That saber kitty doesn't compare to saber tooth tigers WildCat

Go figure, huge Bison aren't around, but their smaller cousins are. Sounds like what happened in the rest of the world. Life was too rough for the biggest beasts. The smaller ones took over. There MUST be environmental factors.

I'd love to see them try, but picking up the resulting mess would be soooo time consuming. Think spagetti sauce.

Good discussion everyone!

 

[arcticpenguin]

That goes against North American Indian ways of life. They respected nature and tried to avoid waste. Spear a few, let the rest go, you know. Unless someone has proof otherwise.

That myth is much disputed.

Societies in the SW USA apparently collapsed due to deforestation.

Speaking of proof, do you have any either?

http://sipapu.gsu.edu/timeline/timeline700.html

Most Anasazi groups were also almost fully sedentary, although household and village abandonments no doubt occurred frequently in response to changing climatic factors, human-induced deforestation, overuse of agricultural lands, or changing social and political contexts.

http://news.nationalgeographic.com/news/2001/06/0601_wireanasazi.html

The myth of the Anasazi as "noble savages" has been replaced by that of "bloodthirsty savages," notes Randall McGuire of Binghamton University. But neither stereotype addresses the truth—that of a culture like any other, sharing in both peaceful and violent times, he says.

 

[neutrino_cannon]

When species get outside their natural range, they can proliferate as they didn't in their home range. We all know the examples: rabbits in Australia, kudzu in the SE USA, 'killer bees', brown tree snakes in Hawaii and other islands.

Maybe man left behind the natural checks on his population when he left Africa (malaria and other diseases? man-eating predators?)

The brown tree snake was never introduced to hawaii, people killed the birds off there. The brown tree snake did get introduced to gaum, however, and killed all the birds there. Fortuantlely there are no snakes in hawaii, and if there ever are any introduced, you can bet your last dollar that the government there will do it's darndest to kill them off as soon as possible.

Whens sea levels dropped during the ice age there were a lot of migrations to other continents, especially North and South America where the exchange had severe effects on both faunas.

The climactic changes in North America changed the grasslands from tall grasses to shorter grasses. This, along with hunting can probably explain the mammoth extinctions. Smilodon too, would have required tall grasses in order to get within lethal range of it's prey (probably bison antiquas), so when the grass got shorter it was harder for it to operate.

Mastodons, on the other han,d are harder to explain. Mammoths are very different from mastodons, don't confuse them. Mastodons had simpler teeth, and were a more primative line of animals. They were adapted for forest browsing, rather than grazing like a mammoth. Mammoths have very developed teeth for grazing, they look something like a rasp.

While paleo indian hunting may have been a contributing factor for mastodon extinctions, I think it was the rapid evolution of many new types of deer that did them in. Deer and bovids diversified more than any other type of mammal during the pleistocene, and suffered the worst extinctions, probably because there were so many specialized types.

Much of the extinction events were local exterpations, that is removing animals from one continent, but having them surivive on another. There used to be camels (extinct genus) cheetahs (both acionyx and an extinct species of felis) lions, leopards, horses, storks, and other forms in north america now only found in the old world, but not totally extinct. The pleistocene envioronement was different, fundamentally. Instead of today's wide "bands" of ecosystems it was more of a patchwork of ecosystems. This led to a plethora of specialized forms that could be easily extincted by either hunting or climatic change.

What we do know is that the extictions of all the large land animals in the pacific and Indian oceans are a result of humans, either directly or indirectly. There are many species, especialy from the New World that could not have been exterminated by humans, either because they died out too early (in the case of glyptodonts and many ground sloths, as well as phorusrhacids and notoungulates) or because human hunting is implausible or absurd (in the case of terators and storks. I mean, come on, who hunts storks and vultures for food?). There are, however, many species that may have been human victems, especially among large mammals.

Mammoths did not evolve into elephants, elelaphas and loxodonta evolved in the late pliocene and early pleistocene. Today's rhinos are not the descendants of cleodonta and elasmotherium. With the exception of the ancient bison, no large bodied animal that we have solid evidence for human hunting managed to become smaller or more adaptable. I'd say that's a smoking gun.

 

[arcticpenguin]

The brown tree snake was never introduced to hawaii, people killed the birds off there. The brown tree snake did get introduced to gaum, however, and killed all the birds there. Fortuantlely there are no snakes in hawaii, and if there ever are any introduced, you can bet your last dollar that the government there will do it's darndest to kill them off as soon as possible.

http://biology.usgs.gov/s+t/noframe/x181.htm

The many brown tree snakes on Guam make it probable that they may disperse as passive stowaways in ship and air traffic to other islands and the U.S. mainland (Fritts 1987, 1988; McCoid and Stinson 1991). To date, stowaway brown tree snakes have arrived in the northern Marianas Islands (Saipan, Rota, and Tinian); Marshall Islands (Kwajalein Atoll); Cocos Island near Guam; Okinawa; Diego Garcia in the Indian Ocean; Oahu Island, Hawaii; and Corpus Christi, Texas (Fritts 1988; unpublished manuscript).

http://inouye.senate.gov/98pr/98pr45.html

WASHINGTON, D.C. -- United States Senator Daniel K. Inouye announced today that the Senate Appropriations Committee approved $2.6 million in the Interior Department's Budget to continue and expand use of existing techniques to control brown tree snakes and prevent their introduction to Hawaii, while at the same time conducting additional research to develop and implement new and better control methods. This funding is a $1 million increase over last year's allocation, and is in addition to another $1 million that Senator Inouye obtains each year in the Defense Department's budget for brown tree snake control.

 

[Eos of the Eons]

That myth is much disputed.

Societies in the SW USA apparently collapsed due to deforestation.

Speaking of proof, do you have any either?

Nope Just heard the myths.

Mammoths did not evolve into elephants, elelaphas and loxodonta evolved in the late pliocene and early pleistocene. Today's rhinos are not the descendants of cleodonta and elasmotherium. With the exception of the ancient bison, no large bodied animal that we have solid evidence for human hunting managed to become smaller or more adaptable. I'd say that's a smoking gun.

Did those that didn't evolve from each other have common ancestors? You'd think that would explain the similiarity between Rhinos, elephants, and the larger ones you mentioned. It would just speak to the smaller more adaptable models surviving better.

We had big reptiles, and we had big mammals. They are all done in - I feel - because it is harder for huge animals to survive. The bigger you are, the harder you fall-for whatever variety of reasons from environment to hunters.

Good information in your post! From the grasses to the Indian Ocean. Lots to think about.

 

[Hexxenhammer]

We had big reptiles, and we had big mammals. They are all done in - I feel - because it is harder for huge animals to survive. The bigger you are, the harder you fall-for whatever variety of reasons from environment to hunters.

Bigger is often better. Depends on the environment. It was obviously beneficial to be be big like sauropods and mammoths or they would never have evolved that way. Sauropods were around for millions and millions of years and just kept getting bigger and bigger for awhile (brachiosaurus, seismosaurus, ultrasaurus, holyfreakinhugeasaurus (kidding with the last one))so there must have been a benefit. An obvious one is defense. Even an allosaurus isn't going to mess with a sauropod that can crush it with a little tail swipe. Same with mammoth. It's easier to stay warm when you're big, and those nasty sabertooth tigers didn't mess with you unless you had a calf.

 

[Eos of the Eons]

If it was better they would still be here. It may have been better at one time, but that obviously changed. Same with dinos.

 

[Hexxenhammer]

If it was better they would still be here. It may have been better at one time, but that obviously changed. Same with dinos.

Right. It comes and goes. In a few million years we could have giant animals again. Here's hoping for giant hamsters.

 

[Eos of the Eons]

What about us?

 

[Dancing David]

The lovingly noble native american with an intuitive understanding of natures balance,

except for the idea that they may have been the major source of wildfire in North America, apparently when needing to make a camp some tribes would just knock a hole in a fallen tree and start the sucker on fire, it burns for days....

Thanks all, one of the most civil discussions on the board.