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What killed the cave bear? Scientists think they have the answer – CBC News

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Genetic research that reconstructed the past population dynamics of the cave bear, a prominent prehistoric denizen of Europe, implicates Homo sapiens rather than climate cooling in the Ice Age extinction of these brawny plant-loving beasts.

Scientists said on Thursday they obtained genome data from 59 cave bears from bones unearthed at 14 sites in France, Germany, Italy, Poland, Serbia, Spain and Switzerland.

Using this, they detected a population downturn roughly 50,000 years ago coinciding with the arrival of our species in eastern Europe and then a dramatic decline starting about 40,000 years ago coinciding with the spread of Homo sapiens throughout Europe. It ultimately went extinct about 20,000 years ago.

The cave bear (scientific name Ursus spelaeus) was one of the charismatic inhabitants of Ice Age Europe alongside animals like the cave lion, wooly rhino, wooly mammoth and steppe bison. It was as big as a polar bear but strictly herbivorous. Firmly in the consciousness of humans in Europe, the bear was depicted in prehistoric cave paintings.

There has been a scientific debate about whether a cooling climate doomed the bears by reducing vegetation central to their diet or whether it was human encroachment including hunting and taking over the caves where the bears hibernated and gave birth.

The steep population decline identified in the study predated climate cooling associated with the most recent Ice Age, said paleogeneticist Verena Schuenemann of the University of Zurich in Switzerland.

Survived 2 cold stretches

The bear’s population also had remained stable for long periods prior to that, including two pronounced cold stretches and multiple other cooling episodes, Schuenemann added.

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Homo sapiens originated in Africa more than 300,000 years ago, later spreading worldwide. The study offered fresh evidence that the arrival of Homo sapiens presaged doom for numerous species across Eurasia, the Americas and Australia.

“There is more and more evidence that modern humans have played a determinant role in the decline and extinction of large mammals once they spread around the planet, starting around 50,000 years ago,” biogeologist Hervé Bocherens of the University of Tuebingen in Germany said.

“This happened not just by hunting these mammals to extinction, but by causing demographic decline of keystone species, such as very large herbivores, that led to ecosystems’ collapse and a cascade of further extinctions,” Bocherens added.

Before the arrival of Homo sapiens, the bear’s population had remained robust even though it shared its territory with another human species, the Neanderthals, who also went extinct after Homo sapiens invaded Eurasia.

The research was published in the journal Scientific Reports.

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A giant full beaver moon set to dazzle Metro Vancouver skies – Vancouver Courier

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While it is getting darker earlier in Metro Vancouver, this month’s full beaver moon promises to illuminate the night sky.

The November full moon is thought to have derived its funny name because it occurred during the optimal time to trap the furry creatures. In fact, both colonial Americans as well as the Algonquin tribes referred to it as such.

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“Why this name? Back then, this was the month to set beaver traps before the swamps froze, to ensure a supply of warm winter furs,” reports Farmer’s Almanac.

While it is commonly known as the beaver moon, it was also called the Full Frost Moon by other North American Tribes.

According to the Old Farmer’s Almanac, the moon will be fullest during the day on Tuesday, Nov. 12. However, Vancouver stargazers will still be able to see the nearly-full moon in all her celestial glory the night before (Nov. 11) as well as later that night (Nov. 12).

What’s more, this full moon casts long, hauntingly beautiful shadows in the Northern Hemisphere. They are similar to those cast by the midday summer sun, as the moon is extremely high in the sky during this time.

Stargazers should opt to travel as far away from city lights as possible in order to avoid light pollution that will obscure the clarity of heavenly bodies. While this works best the in more remote places, anywhere that has a higher elevation will also provide more ideal viewing conditions.

Click here for original article.

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All-female space walk a starry-eyed achievement: The Statesman – The Straits Times

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NEW DELHI (THE STATESMAN/ASIA NEWS NETWORK) – It is a starry-eyed achievement almost literally.

Christina Koch and Jessica Meir, two NASA astronauts, have crafted space history by embarking on what they call the first all-female space walk.

Tasked with replacing a failed power control unit, their performance has been decidedly spectacular as they floated feet-first out of the International Space Station’s (ISS) Quest airlock on Friday (Oct 18).

The spacewalk, known as an extra-vehicular activity (EVA) in the jargon of astronauts, took place seven months after the originally scheduled date for an “all-female outing”, which had to be dropped because the ISS had only one medium-sized spacesuit on board.

The agency sent up a second medium spacesuit in October.

From space to ground zero, the happiest thought at the moment must be that both the achievement and empowerment of women are now manifest in the rarified atmosphere of space.

Very appropriately has the significance of the spacewalk been summed up by Christina: “I think it’s important because of the historical nature of what we’re doing,” she said ahead of the spacewalk.

“In the past, women haven’t always been at the table. It’s wonderful to be contributing to the space programme at a time when all contributions are being accepted, when everyone has a role. That can lead in turn to increased chance for success.”

On closer reflection, more than the space-walk, it is the assignment that is historic to fix a failed power control unit.

Previously, 14 women and 213 men had carried out spacewalks. The first woman was the Russian cosmonaut Svetlana Savitskaya, who went outside the USSR’s Salyut 7 space station in 1984.

Video footage from the astronauts’ helmet cameras, as they dangled 260 miles above Earth, provided a live stream of the painstaking operation to carry the new hardware, install it and then return the faulty battery to the airlock for a postmortem back on Earth into why it failed.

Their work in space will, therefore, be followed up by the labs on Earth.

Exceptional must be the projected coordination between space science and pure science as the world knows it.

At 40, Christina is due to remain on the ISS until February, bringing her total time in space to 328 days, the longest single spaceflight by a woman and just short of Scott Kelly’s 340-day record.

Researchers are collecting extensive biomedical data on the impact of spaceflight on her system.

The majority of data available is on male astronauts, but there is some evidence that there are sex differences in response to a space environment.

One study found that women are more likely than men to suffer faintness as a result of “orthostatic hypotension”, a cardiovascular issue.

Men appear more prone to vision changes caused by spaceflight associated neuroocular syndrome (Sans).

A flight to space has a lot to bear on human health. The contretemps notwithstanding, NASA has reached a milestone.

The Statesman is a member of The Straits Times media partner Asia News Network, an alliance of 24 news media entities.

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NASA Invites Media to Next SpaceX Space Station Cargo Launch – PRNewswire

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WASHINGTON, Oct. 22, 2019 /PRNewswire/ — Media accreditation is open for the launch of the next SpaceX delivery of science investigations, supplies, and equipment to the International Space Station.

A SpaceX Dragon cargo spacecraft is scheduled to launch on a Falcon 9 rocket from Space Launch Complex 40 at Cape Canaveral Air Force Station (CCAFS) in Florida no earlier than Wednesday, Dec. 4 at 12:48 p.m. EST.

Media prelaunch and launch activities will take place at NASA’s Kennedy Space Center and neighboring CCAFS. Credentialing deadlines are as follows:

  • International media without U.S. citizenship must apply by 4:30 p.m. EDT Sunday, Oct. 27.
  • U.S. media must apply by 4:30 p.m. EST Friday, Nov. 15.

All media accreditation requests should be submitted online at:

https://media.ksc.nasa.gov

For questions about accreditation, please email ksc-media-accreditat@mail.nasa.gov. For other questions, contact Kennedy’s newsroom at 321-867-2468.

Each resupply mission to the station delivers scientific investigations in the areas of biology and biotechnology, physical sciences, Earth and space science. Advances in these areas will help to keep astronauts healthy during long-duration space travel and demonstrate technologies for future human and robotic exploration beyond low-Earth orbit to the Moon and Mars. Space station research through the ISS National Lab also provides opportunities for other U.S. government agencies, private industry, and academic and research institutions, to conduct microgravity research that leads to new technologies, medical treatments, and products that improve life on Earth.

Highlights of space station research that will be facilitated by research aboard this SpaceX Dragon mission include testing the effectiveness of a device to separate and capture water droplets suspended in an air stream, delivering a next-generation spaceborne system to image Earth in higher spectral resolution than currently possible onboard the TERRA satellite, and testing conditions to develop an inexpensive and scalable process to manufacture optical materials in space.

Cargo resupply from U.S. companies ensures a national capability to deliver critical science research to the space station, significantly increasing NASA’s ability to conduct new investigations at the only laboratory in space. This is the 19th SpaceX mission under NASA’s Commercial Resupply Services contract.

The International Space Station is a convergence of science, technology and human innovation that demonstrates new technologies and enables research not possible on Earth. The space station has been occupied continuously since November 2000. In that time, 239 people and a variety of international and commercial spacecraft have visited the orbiting laboratory. The space station remains the springboard to NASA’s next great leap in exploration, including future missions to the Moon and eventually to Mars.

For launch countdown coverage, NASA’s launch blog, and more information about the mission, visit:

https://www.nasa.gov/spacex

SOURCE NASA

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