The 6th Mass Extinction

[rowan]

They apparently had a bigger brain capacity than homo sapiens and may have been more intelligent. & they existed for at least twice as long as we have so far - three or four times as long, according to some estimates. So best not revive the species via genome editing, or they might just end up taking over!

Yes to all of that; the only real surprise from the article is that Neaderthal diet has been found to range from vegan right up to rhinocerus. Like you, I'd been under the impression that it was "our" team work and blood-thirstiness from being big-game hunters that had set us apart from the small-game and fishing of the Neanderthalls.
Let's be honest though, it'll probably eventually emerge that we simply out-bred them.
We know they were more powerful, probably more intelligent, and capable of speech and weaponry (though IIRC their weapons were a little more "crude" - maybe that was the difference?)

Not sure. The big game hunters were probably in the minority among the Neanderthals, and we were probably more athletic than them, if not also more powerful. Plenty of archaeological evidence of wholesale slaughter exists, and more and more of it with Neanderthal victims as time progresses. What is really curious about the Neanderthals is that they didn't get beyond the hunter-gatherer stage, despite having a few hundred thousand years or so to figure out animal husbandry and agriculture. & although they almost certainly used some kind of language, it seems that it never evolved to a particularly complex stage either.

[morepork]

Mitochondrial DNA and maternal inheritance to the rescue again. Nice synthesis of biology and cultural identity.

http://www.nature.com/nature/journal/va ... 21416.html

Aboriginal Australians represent one of the longest continuous cultural complexes known. Archaeological evidence indicates that Australia and New Guinea were initially settled approximately 50 thousand years ago (ka); however, little is known about the processes underlying the enormous linguistic and phenotypic diversity within Australia. Here we report 111 mitochondrial genomes (mitogenomes) from historical Aboriginal Australian hair samples, whose origins enable us to reconstruct Australian phylogeographic history before European settlement. Marked geographic patterns and deep splits across the major mitochondrial haplogroups imply that the settlement of Australia comprised a single, rapid migration along the east and west coasts that reached southern Australia by 49–45 ka. After continent-wide colonization, strong regional patterns developed and these have survived despite substantial climatic and cultural change during the late Pleistocene and Holocene epochs. Remarkably, we find evidence for the continuous presence of populations in discrete geographic areas dating back to around 50 ka, in agreement with the notable Aboriginal Australian cultural attachment to their country.

[rowan]

They apparently had a bigger brain capacity than homo sapiens and may have been more intelligent. & they existed for at least twice as long as we have so far - three or four times as long, according to some estimates. So best not revive the species via genome editing, or they might just end up taking over!

Yes to all of that; the only real surprise from the article is that Neaderthal diet has been found to range from vegan right up to rhinocerus. Like you, I'd been under the impression that it was "our" team work and blood-thirstiness from being big-game hunters that had set us apart from the small-game and fishing of the Neanderthalls.
Let's be honest though, it'll probably eventually emerge that we simply out-bred them.
We know they were more powerful, probably more intelligent, and capable of speech and weaponry (though IIRC their weapons were a little more "crude" - maybe that was the difference?)

Not sure. The big game hunters were probably in the minority among the Neanderthals, and we were probably more athletic than them, if not also more powerful. Plenty of archaeological evidence of wholesale slaughter exists, and more and more of it with Neanderthal victims as time progresses. What is really curious about the Neanderthals is that they didn't get beyond the hunter-gatherer stage, despite having a few hundred thousand years or so to figure out animal husbandry and agriculture. & although they almost certainly used some kind of language, it seems that it never evolved to a particularly complex stage either.

An interesting theory was put forward a few years ago that the key to homo sapiens' success - and further evolution - was the domestication of dogs. As primarily big game hunters we pursued the same prey and gradually learned to collude with our canine counterparts; something Neanderthals, as primarily small game hunters, never got around to, judging by archaeological findings and cave paintings, etc. It's highly unlikely the homo sapien-dog relationship would have developed to the point that we could have actually used them against our enemies, but by partly domesticating them we became more successful as a species and thereby vastly more numerous. The domestication of one species also led to the eventual domestication of others, evidently.

[kk67]

Drought in sub-Sahara is getting worse. One diaspora going North and another going South. We have fecked that continent so badly.
Pure greed has created hundreds of years of rape, slavery, starvation, genocide and extinction. The Dutch, the French, and the English were there first but now everyone is joining in. The rape continues.
History will judge our treatment of Africa,......and none of us will be innocent.
We'll look just like those B+W speeded up people. With identically rubbish justifications.

[rowan]

Drought in sub-Sahara is getting worse. One diaspora going North and another going South. We have fecked that continent so badly.
Pure greed has created hundreds of years of rape, slavery, starvation, genocide and extinction. The Dutch, the French, and the English were there first but now everyone is joining in. The rape continues.
History will judge our treatment of Africa,......and none of us will be innocent.
We'll look just like those B+W speeded up people. With identically rubbish justifications.

Indeed. Neo-colonialism. The US had picked up where the British & French et al left off. (I know, they didn't leave off entirely - if at all) . . .

[rowan]

[rowan]

Interesting update on the Cretaceous–Paleogene extinction event, which occurred approximately 66 million years ago:

No one could have seen the catastrophe coming. Dinosaurs stalked each other and munched on lush greens as they had for over 170 million years. Pterosaurs soared in the air, mosasaurs splashed in the seas, and tiny mammals scurried through the forest on what was just another day in the Late Cretaceous.

Then the world changed in an instant. A chunk of extraterrestrial rock over 6 miles wide slammed into what would eventually become known as Mexico’s Yucatan Peninsula. The shock was a planet-scale version of a gunshot. Earth would never be the same again.

But what actually happened on the day the asteroid struck? By sifting through the rock record, experts are putting together a nightmarish vision of one of the worst days in the history of our planet.

Some of the damage is easy to assess. The crater created by the impact is over 110 miles in diameter, a massive scar half covered by the Gulf of Mexico. But the devil is in the geological details at places around the world, such as signs of a massive tsunami around the Gulf coast. The impact struck with so much force and displaced so much water that within 10 hours an immense wave tore its way along to the coast.

What settled out is a geologic mess: ocean sand on what would have been dry land, and fossils of land plants in areas that should have been the ocean, in a mixed up slurry of ancient sediment. In the part of the world where the tsunami struck, these layers mark a violent boundary between the last day of the Cretaceous and the first of the following period, the Paleocene.

Not that the effects were limited to the area of impact. The blast was enough to cause geologic disturbances, such as earthquakes and landslides, as far away as Argentina—which in turn created their own tsunamis.

As dangerous as the waves were to life in the western hemisphere, however, the heat was worse.

When the asteroid plowed into the Earth, tiny particles of rock and other debris were shot high into the air. Geologists have found these bits, called spherules, in a 1/10-inch-thick layer all around the world.

“The kinetic energy carried by these spherules is colossal, about 20 million megatons total or about the energy of a one megaton hydrogen bomb at six kilometer intervals around the planet,” says University of Colorado geologist Doug Robertson. All of that energy was converted to heat as those spherules started to descend through the atmosphere 40 miles up, about 40 minutes after impact. As Robertson and colleagues wrote in a paper titled “Survival in the First Hours of the Cenozoic”: “For several hours following the Chicxulub impact, the entire Earth was bathed with intense infrared radiation from ballistically reentering ejecta.”

Earth became a world on fire. The friction of falling made each spherule an incandescent torch that quickly and dramatically heated the atmosphere. Any creature not underground or not underwater—that is, most dinosaurs and many other terrestrial organisms—could not have escaped it. Animals caught out in the open may have died directly from several sustained hours of intense heat, and the unrelenting blast was enough in some places to ignite dried-out vegetation that set wildfires raging.

On land, at least, much of Cretaceous life may have been wiped out in a matter of hours. The heat pulse and its after-effects alone severely winnowed back life’s diversity. But the situation turned out to be even more dire.

Read more: http://www.smithsonianmag.com/science-n ... zCVTYXl.99

[rowan]

That's a helluva footprint

The thousands of dinosaur footprints found at Walmadany in Australia's Kimberley region come from at least 21 Cretaceous species, a comprehensive study has revealed. Some of these, at 1.7 meters (5.6 feet) long, are candidates for the largest footprints every found. The collection is unparalleled in the world in diversity recorded at a single site, making it a good thing that plans to destroy the location forever were defeated by one of the country's largest environmental campaigns.

In 2008 the Western Australian government chose Walmadany (also known as James Price Point) as the preferred location to process natural gas from the vast fields off the coast of northwest Australia, despite the existence of cheaper and less environmentally sensitive alternatives.

The decision sparked a huge campaign to protect the site, with the giant dinosaur footprints being highlighted as one reason the area needed to be saved. The Goolarbooloo people, Walmadany's traditional custodians, contacted Dr Steve Salisbury of the University of Queensland to document the prints and reveal as much as possible about the extinct creatures that created them.

“It is extremely significant, forming the primary record of non-avian dinosaurs in the western half the continent and providing the only glimpse of Australia’s dinosaur fauna during the first half of the Early Cretaceous Period,” Dr Salisbury said in a statement. “It’s such a magical place –Australia’s own Jurassic Park, in a spectacular wilderness setting.”

Walmadany aside, Australia's dinosaur record is almost exclusively from the east coast, and millions of years younger than these footprints. Consequently, Salisbury's work provides almost the only window we have into the ecosystem that existed in the Western Australia 127-140 million years ago.

http://www.iflscience.com/plants-and-an ... t-diverse/