Asteroid's 'bad timing' killed off dinosaurs, new evidence shows

'If the asteroid had hit a few million years earlier, or a few million years later, dinosaurs probably wouldn’t have gone extinct.' Photograph: Don Davis/AFP/Getty Images

#Dinosaurs might have survived the catastrophic impact that ended their reign had the devastating asteroid that slammed into the #Earth arrived at a "more convenient time", a scientist has claimed. As a result humans would probably not exist.

The violent collision 66m years ago, which occurred in the area that is now Mexico, triggered tsunamis across the oceans, caused powerful earthquakes and released enough heat to start many fires.

Material thrown into the air descended as acid rain, and also blocked the sun's warmth, cooling the Earth temporarily, perhaps by tens of degrees celsius. A thick blanket of dust that was thrown up darkened the globe, affecting plants and other photosynthesising life.

The devastation wrought by the impact almost certainly explains the sudden death of the land-based dinosaurs, according to fresh analysis of the latest data.

But one scientist on the team said the beasts might have prevailed had the asteroid struck earlier or later than it did.

Steve Brusatte, a paleontologist at Edinburgh University, was in an international team of researchers who reviewed the evidence on dinosaur extinction. The group looked at work done on prehistoric climate and temperatures, changes in sea levels, volcanic activity and biodiversity, before reaching a consensus that the asteroid was the prime culprit.

"The asteroid almost certainly did it but it just so happened to hit at a bad time when dinosaur ecosystems had been weakened by a loss of diversity," Brusatte said. "If the asteroid had hit a few million years earlier, or a few million years later, then dinosaurs probably wouldn't have gone extinct."

The scientists' report, published in Biological Reviews, found that while, largely, the dinosaurs were faring well at the time of the asteroid impact, the big plant-eating types, including the horned triceratops and duck-billed dinosaurs, had suffered a loss of biodiversity.

The loss of biodiversity in plant-eating dinosaurs left fewer animals at the bottom of the food chain for larger beasts to prey on.

"The decline made those ecosystems at the very end of the cretaceous [period], when the asteroid hit, considerably more vulnerable to collapse than those ecosystems that existed even a few million years before," said Brusatte. "There is strong reason to believe that if the asteroid had hit a few million years earlier dinosaurs would have been better able to cope."

Dinosaur biodiversity rose and fell throughout their time on Earth over 150m years. Brusatte said he suspected that given a few million years more the large plant-eaters would have recovered again, making the ecosystem more able to withstand a massive impact.

The asteroid, which had a diameter of about six miles struck the Yucatan peninsula and left a crater, now known as the Chicxulub, measuring 12 miles deep by 124 miles wide.

The collision wiped out about 80% of the Earth's species alive on Earth at the time. The non-avian dinosaurs were killed off completely, but others survived and became the direct ancestors of birds.

Though devastating for the dinosaurs, the asteroid strike cleared the way for other animals to gain ground and thrive on the planet.

"If the asteroid didn't hit, I have no reason to believe they'd have gone extinct. There is a good chance they would still be with us today. And if dinosaurs didn't go extinct, then mammals would have never had their opportunity to blossom. So if it wasn't for that asteroid, then humans probably wouldn't be here. It's as simple as that," Brusatte said.

Strong as the evidence is for the asteroid wiping out the dinosaurs, there are huge gaps in dinosaur experts' knowledge.

There is only one site, the Hell Creek rock formation in the US, spread across Wyoming, the Dakotas and Montana, that has a good fossil record covering the final years of the cretaceous period. To round out the picture of the dinosaurs' fate, far more fossils from other regions are needed.

Paul Barrett, a paleontologist and co-author of the paper, based at the Natural History Museum, in London, said: "The great dinosaur mass extinction has been one of the world's biggest mysteries and has captured the imaginations of many people. Although some types of dinosaurs were already declining in numbers before the famous asteroid impact, in most cases this impact was the smoking gun for the cause of the extinction.

"This new work provides the best evidence for sudden dinosaur extinction and for tying this event to the asteroid impact rather than other possible causes such as the longer-term effects of the extensive volcanic activity that occurred at the end of the cretaceous." The Guardian

More Than 20,000 Elephants Thieved In Africa In 2013

Dianne Blell via Getty Images

GENEVA (AP) — More than 20,000 elephants were poached last year in #Africa where large seizures of smuggled ivory eclipsed those in #Asia for the first time, international #wildlife regulators said Friday.

Eighty percent of the African seizures were in Kenya, Tanzania and Uganda, three of the eight nations required to draw up plans to curb ivory smuggling, officials with the Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES) reported.

The report says poaching is increasing in Central African Republic, but declining in Chad. But CITES, which regulates 35,000 species of plants and animals and which banned ivory trade in 1989, says the overall poaching numbers in 2013 dropped from the previous two years.

"We are seeing better law enforcement and demand-reduction efforts across multiple countries, as well as greater political and public attention to this unfolding crisis," said John Scanlon, the CITES secretary-general.

About 28 percent of Africa's elephants are in eastern Africa, but most of them — close to 55 percent — are in southern Africa. Some populations of elephants continue to face an immediate threat of local extinction.

The BBC notes that though the overall poaching levels in 2013 declined, the report found that poaching levels exceeded the elephant birth rate, posing a serious threat to the survival of Africa's elephants. CITES Secretary-General John E Scanlon said "Africa's elephants continue to face an immediate threat to their survival from high levels of poaching for their ivory," according to the BBC report. More from the report can be found in a press release from CITES.

Young Bangal Tiger Died in Karachi Zoo

Screen-grab of DawnNews footage shows the dead Bengal tiger at the Karachi zoo.—DawnNews

KARACHI: A young Bengal #tiger, imported only two years ago from Belgium, died at the #Karachi Zoological Gardens on Saturday, officials said.

Zoo director Fahim Khan said the big cat, which was hardly six years old, died of a gastrointestinal problem.

The tiger, according to sources, had been suffering from a deadly disease for months. Due to digestive problems, the poor animal had reportedly stopped eating and had become unable to move freely due to weakness.

Khan said no negligence could be found on part of the zoo administration which could be attributed to the animal’s death.

Sources said the zoo administration had called quite a few experts to examine the animal but no treatment had proved effective.

The ailing tiger was bought with its mate, aged between three and four years, at a cost of Rs7.1 million from Belgium through a local animal dealer in 2012.


A Bengal tiger died at the same zoo in 2012 after having remained ill for some time. Zoo officials claimed that the ageing big cat had suffered a third attack of paralysis and couldn’t survive.

National animal of both Bangladesh and India, the Bengal tiger (Panthera tigris tigris) has been classified as endangered by the International Union for Conservation of Nature.

The total population of the endangered species is estimated at fewer than 2,500 individuals in the world.

Wandering Oregon Wolf May Have Found Mate

MEDFORD, Ore. — Oregon's famous wandering gray wolf, dubbed OR-7, may have found the mate he has trekked thousands of miles looking for, wildlife authorities said Monday. It's likely the pair spawned pups, and if confirmed, the rare predators would be the first breeding pair of wolves in the Oregon's Cascade Range since the early 1900s.

Officials said cameras in the Rogue River-Siskiyou National Forest in the southern Cascades captured several images of what appears to be a female wolf in the same area where OR-7's GPS collar shows he has been living.

U.S. Fish and Wildlife Service biologist John Stephenson said it is not proof, but it is likely the two wolves mated over the winter and are rearing pups that would have been born in April. Biologists won't start looking for a den until June, to avoid endangering the pups.

Wolf standing on the road

"It's amazing that he appears to have found a mate," Stephenson said. "I didn't think it would happen. It makes me more impressed with the ability of wolves to survive and find one another."

Young #wolves typically leave their pack and strike out for a new territory, hoping to find a mate and start a new pack.

OR-7 has been looking for a mate since leaving the Imnaha pack in northeastern Oregon in September 2011. His travels have taken him thousands of miles as he crossed highways, deserts and ranches in Oregon, moved down the spine of the Cascade Range deep into Northern California and then back to Oregon, all without getting shot, having an accident or starving.

Federal Endangered Species Act protections for wolves have been lifted in eastern Oregon, where the bulk of them reside, but they remain in force in the Cascades. Protections for the animals have also ended in the last several years in the Northern Rockies and western Great Lakes.

The #U.S. Fish and #Wildlife Service has proposed ending the listing across most of the rest of the country as populations have rebounded. A final decision is expected later this year.

If a wolf was going to start a pack in a new part of Oregon, ranchers should be glad it is OR-7, who has no history of preying on livestock, said Bill Hoyt, past president of the Oregon Cattlemen's Association. The group supports Oregon's wolf recovery plan and is looking forward to the day the predator's numbers and range expand enough for their protections to be removed.

Steve Pedery, conservation director of Oregon Wild, said the news was "spectacular." The conservation group won a court ruling barring the state from killing two members of OR-7's home pack for preying on livestock and later won a settlement strictly limiting when wolves can be killed.

"It goes to show that when we act on America's best impulses for the environment, amazing things can happen. We can bring endangered species back," he said.

Stephenson expected the battery on OR-7's GPS collar to die soon, so the biologist set up trail cameras based on the wolf's most recent whereabouts. The GPS locations also showed OR-7 was staying within a smaller area, common behavior when wolves have pups to feed.

When he checked the cameras last week, Stephenson said one had recorded a black wolf he had not seen before. An hour later, OR-7 was photographed on the same camera. The black wolf was confirmed to be female because she squatted to urinate.

Officials had planned to let OR-7's collar die, but now that he appears to have found a mate, he will be fitted with a new one this summer to monitor the pack.

Stephenson said officials had no idea where the female came from.
Source: NBC News