Month: September 2016

375 top scientists warn of ‘real, serious, immediate’ climate threat

Yesterday, 375 of the world’s top scientists, including 30 Nobel Prize winners, published an open letter regarding climate change. In the letter, the scientists report that the evidence is clear: humans are causing climate change. We are now observing climate change and its affect across the globe. The seas are rising, the oceans are warming, the lower atmosphere is warming, the land is warming, ice is melting, rainfall patterns are changing and the ocean is becoming more acidic.

These facts are incontrovertible. No reputable scientist disputes them. It is the truth.

Despite these facts, the letter reports that the US presidential campaign has seen claims that the earth isn’t warming, or it is only a natural warming, or that climate change is a hoax. These claims are false. The claims are made by politicians or real estate developers with no scientific experience. These people who deny the reality of climate change are not scientists.

The Guardian

A Single Migration From Africa Populated the World, Studies Find

Modern humans evolved in Africa roughly 200,000 years ago. But how did our species go on to populate the rest of the globe?

The question, one of the biggest in studies of human evolution, has intrigued scientists for decades. In a series of extraordinary genetic analyses published on Wednesday, researchers believe they have found an answer.

In the journal Nature, three separate teams of geneticists survey DNA collected from cultures around the globe, many for the first time, and conclude that all non-Africans today trace their ancestry to a single population emerging from Africa between 50,000 and 80,000 years ago.

“I think all three studies are basically saying the same thing,” said Joshua M. Akey of the University of Washington, who wrote a commentary accompanying the new work. “We know there were multiple dispersals out of Africa, but we can trace our ancestry back to a single one.”NYTimes

Cats crossed continents to be close to us, says gene study

Cats like to think they don’t need us, but a new study into feline genetics has indicated that the global kitty population only boomed when they moved in with humans. The research, presented last week and reported by Nature, seems to show two distinct waves of growth in cat numbers: first around 10,000 years ago as humans first started cultivating crops, and second as we started taking to the seas.

CAT FAMILIES FROM EGYPT ENDED UP IN BULGARIA

The researchers behind the study sequenced DNA from more than 200 cats of various generations discovered in tombs, burial sites, and other archaeological sites, from as far back as 15,000 years ago, to animals born in the 1700s. Even among this limited sample, they found links in mitochondrial DNA, genetic information passed down through the maternal line only — suggesting that cat families had either moved or been taken near to human civilizations. This mitochondrial connection was spotted between wild cats found in the Middle East and creatures discovered close to the fertile east Mediterranean, a region well-known for its early agriculture. Researchers also found connections between cats that lived millennia later, linking mummified kitties discovered in Egyptian tombs with cats found as far away as Bulgaria, Turkey, and sub-Sarahan Africa.

TheVerge

Turning off this newly discovered brain pathway could help us block fearful memories

Scientists now know how to make you forget your fears — at least if you’re a mouse. By turning off a newly discovered brain pathway, scientists were able to make mice lose their fear of a shock. It’s early research, but it may point toward methods that could help people with anxiety and PTSD.

After finding a new pathway in the brain important for creating fearful memories, scientists trained mice to fear a high-pitched tone by shocking the rodents every time they heard it, according to a study published today in Nature Neuroscience. They waited til the rodents would freeze in fear even without the shock before proceeding to the next stage: viewing the mouse brains. Using a specialized microscopy technique, the scientists observed that there was growth in the neurons along that pathway. So what would happen if they could turn that pathway off?

TheVerge