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Humans, Not Climate Change, Wiped Out Australian Megafauna (phys.org)
"New evidence involving the ancient poop of some of the huge and astonishing creatures that once roamed Australia indicates the primary cause of their extinction around 45,000 years ago was likely a result of humans, not climate change," reports Phys.org. schwit1 quotes their report on new analysis of a prehistoric sediment core from the Indian Ocean off the coast of Australia.
The core contains chronological layers of material blown and washed into the ocean, including dust, pollen, ash and spores from a fungus called Sporormiella that thrived on the dung of plant-eating mammals, said CU Boulder Professor Gifford Miller, who participated in the study... Fungal spores from plant-eating mammal dung were abundant in the sediment core layers from 150,000 years ago to about 45,000 years ago, when they went into a nosedive, said Miller... "The abundance of these spores is good evidence for a lot of large mammals on the southwestern Australian landscape up until about 45,000 years ago," he said. "Then, in a window of time lasting just a few thousand years, the megafauna population collapsed."
The Australian collection of megafauna some 50,000 years ago included 1,000-pound kangaroos, 2-ton wombats, 25-foot-long lizards, 400-pound flightless birds, 300-pound marsupial lions and Volkswagen-sized tortoises. More than 85 percent of Australia's mammals, birds and reptiles weighing over 100 pounds went extinct shortly after the arrival of the first humans, said Miller... "There is no evidence of significant climate change during the time of the megafauna extinction."
The article adds that last year Miller also identified the first direct evidence that humans preyed on Australian megafauna -- burned eggshells from a 400-pound bird.
The Australian collection of megafauna some 50,000 years ago included 1,000-pound kangaroos, 2-ton wombats, 25-foot-long lizards, 400-pound flightless birds, 300-pound marsupial lions and Volkswagen-sized tortoises. More than 85 percent of Australia's mammals, birds and reptiles weighing over 100 pounds went extinct shortly after the arrival of the first humans, said Miller... "There is no evidence of significant climate change during the time of the megafauna extinction."
The article adds that last year Miller also identified the first direct evidence that humans preyed on Australian megafauna -- burned eggshells from a 400-pound bird.
This reminds me of cheesy old movies and TV shows about primitive "cave men" constantly on the run from predatory dinosaurs -- Land of the Lost, Land That Time Forgot, etc. Except I think now we see that it would have been the dinosaurs doing the running, while the cave women back home got the BBQ pits warmed up.
Serene, peaceful, in tune with nature, never takes more than he gives... And wipes out numerous complete (and unique) species.
Considering that Europeans still have to suffer demands for reparation for such things as slavery, colonisation, and the crusades, one cannot help but wonder if a demand for compensation for the irreparable damage to the ecosystem made by the aboriginals is also possible.
They were probably delicious.
Mostly random stuff.
We can look to our recent history and see the same extinction process created by man. The passenger pigeon, Tasmanian tiger, the Dodo, Great auk, Quaggas, Carolina parakeet and so on. Even today there are several species who are literally on the brink of going extinct, including the northern white rhino of which the last known male of its species is under 24 hour guard to protect it from poachers. Had it not been for Teddy Roosevelt, the American bison would most likely also be extinct, slaughtered by the literal tens of thousands as short as 130 years ago.
Man-made extinction also occurs in human populations. How many different Native American tribes were exterminated either because of Europeans or their Native American allies? How about those of Central and South America or those in the Far East?
We can see the same extinction process in places like Borneo where the habitat of orangutans is being wiped out due to illegal farming or clear cutting for palm oil trees, and similar processes under way in Madagascar where many animals exist in no other place on the planet, such as the ring-tailed lemur of which only an estimated 2,500 still survive.
Anyone who says man doesn't and can't have an effect on the environment is simply blind to reality.
Tell that to the mammoths and sabretooths.
> It is possible that a short lived disaster could have caused the die off. Something like a nearby super volcano or an asteroid impact.
They found evidence of a constant decrease in populations over thousands of years, without a corresponding climatic change. It is possible, or perhaps likely that a event like that finished them off. But something other than climate change pushed these local populations to the brink first, and it started at the same time as humans showed up.
Yet, you got lied to and believed that climate change wiped out the Australian megafauna.
Lied to? By whom? Seems like Human impact has been the favoured explanation since before the turn of the century: Pleistocene Extinction of Genyornis newtoni: Human Impact on Australian Megafauna. Largely on account of the fact that climate change was modest over the period of extinction: "More than 700 dates on Genyornis eggshells from three different climate regions document the continuous presence of Genyornis from more than 100,000 years ago until their sudden disappearance 50,000 years ago, about the same time that humans arrived in Australia. Simultaneous extinction of Genyornis at all sites during an interval of modest climate change implies that human impact, not climate, was responsible."
Most people were probably not aware of this one way or another before reading this Slashdot post. Those that looked it up on Wikipedia would have found that Humans are thought to be the cause: "Analysis of oxygen and carbon isotopes from teeth of megafauna indicate the regional climates at the time of extinction were similar to arid regional climates of today and that the megafauna were well adapted to arid climates.[5] The dates derived have been interpreted as suggesting that the main mechanism for extinction was human burning of a landscape that was then much less fire-adapted; oxygen and carbon isotopes of teeth indicate sudden, drastic, non-climate-related changes in vegetation and in the diet of surviving marsupial species. However, early Australian Aborigines appear to have rapidly eliminated the megafauna of Tasmania about 41,000 years ago (following formation of a land bridge to Australia about 43,000 years ago as ice age sea levels declined) without using fire to modify the environment there,[7][8][9] implying that at least in this case hunting was the most important factor. It has also been suggested that the vegetational changes that occurred on the mainland were a consequence, rather than a cause, of the elimination of the megafauna.
So do *you* care to jive the Fourth Crusade and the Sack of Constantinople with your statement?
The world's burning. Moped Jesus spotted on I50. Details at 11.
Maybe the noble savage really is "serene, peaceful, in tune with nature, never takes more than he gives", precisely because their ancestors learned such a hard lesson and taught their descendants "don't mess up like we did". (I'm not saying it is so, just that it is consistent with the observation of prehistorical extinctions.)
Quattuor res in hoc mundo sanctae sunt: libri, liberi, libertas et liberalitas.
There was some climate change occurring as a result of the widening gap between South America an Antartica at Tierra del Fuego. The increase in water flow of the Antarctic Circumpolar Current helps with the deforestation of Australia. There was a major event that widened the gap about 100,000 to 50,000 years ago which might have led to the migration to Australia. As the water flow increases, southern Australia will get drier.
Where the hell did you get that? Yes, there were people driven by religious zeal and whatnot, but for most of the European nobility the crusades were a chance to conquer a land for themselves, for as second born they had no claim to the land the firstborn got.
If you go down the list of noble participants of the various crusades, you will come up with a handful of landed leaders who wanted to ensure that the new "owners" will swear fealty to them and a huge number of landless nobles who wanted some.
We used to have a Bill of Rights. Now, with the rights gone, all we have left is the bill.
Also to note the Crusades were not really about saving Jerusalem from those evil Muslims as some would like people to think. Jerusalem was under Arab rule starting in 638. The first Crusade was 1095. While news in the old world didn't travel fast, do you believe it took 400 years for the Christians in Europe to learn their beloved holy city was under Arab rule? Another thing to note: Jews fought along side Muslims against Christians in the Siege of Jerusalem in 1099.
Well, there's spam egg sausage and spam, that's not got much spam in it.
Volcanoes co2 emissions lessen as planet still cools, plants who depend on rich co2 die back, less o2 emitted, less breathable air, animals tend to have a small air inway, o2/fuel requirements to keep a 1000lb animal active > available resources = most don't make it
Plants are stupid. They should all die.
I laugh at the thought that some plants have suffered sub-optimal, even stunted growth in the run up to the Industrial Revolution. For many plants CO2 was almost down to 'gasping' level. It is funny to imagine plants gasping and panicking for breath. I am angry at volcanoes for helping to feed plants now and then, but at least volcanoes blot out the sun and lengthen Winter so you can imagine nasty plant things suffering in other ways too. Now Trump man comes along and wants to feed the plants with more fossil fuel and stirring up swamp gas. He should mind his own business and leave the plants alone. Did you know that if you move a house plant a little farther from the window every day it will begin to lean towards it? Then all of a sudden you turn the pot around. It's hilarious!
I hate plants. Plants are stupid.
<blink>down the rabbit hole</blink>