The fossil and genetic evidence agree that modern humans originated in Africa. The most genetically diverse human populations—the groups that have had the longest time to pick up novel mutations—live there today. But the history of what went on within Africa between our origins and the present day is a bit murky.

That’s partly because DNA doesn’t survive long in the conditions typical of most of the continent, which has largely limited us to trying to reconstruct the past using data from present-day populations. The other part is that many of those present-day populations have been impacted by the vast genetic churn caused by the Bantu expansion, which left its traces across most of the populations south of the Sahara.

But a new study has managed to extract genomes from ancient samples in southern Africa. While all of these are relatively recent, dating from after the end of the most recent glacial period, they reveal a distinct southern African population that was relatively large, outside of the range of previously described human variation, and it remained isolated until only about 1,000 years ago.

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Many dog breeds are noted for their personalities and behavioral traits, from the distinctive vocalizations of huskies to the herding of border collies. People have worked to identify the genes associated with many of these behaviors, taking advantage of the fact that dogs can interbreed. But that creates its own experimental challenges, as it can be difficult to separate some behaviors from physical traits distinctive to the breed—small dog breeds may seem more aggressive simply because they feel threatened more often.

To get around that, a team of researchers recently did the largest gene/behavior association study within a single dog breed. Taking advantage of a population of over 1,000 golden retrievers, they found a number of genes associated with behaviors within that breed. A high percentage of these genes turned out to correspond to regions of the human genome that have been associated with behavioral differences as well. But, in many cases, these associations have been with very different behaviors.

Gone to the dogs

The work, done by a team based largely at Cambridge University, utilized the Golden Retriever Lifetime Study, which involved over 3,000 owners of these dogs filling out annual surveys that included information on their dogs’ behavior. Over 1,000 of those owners also had blood samples obtained from their dogs and shipped in; the researchers used these samples to scan the dogs’ genomes for variants. Those were then compared to ratings of the dogs’ behavior on a range of issues, like fear or aggression directed toward strangers or other dogs.

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AI systems have recently had a lot of success in one key aspect of biology: the relationship between a protein’s structure and its function. These efforts have included the ability to predict the structure of most proteins and to design proteins structured so that they perform useful functions. But all of these efforts are focused on the proteins and amino acids that build them.

But biology doesn’t generate new proteins at that level. Instead, changes have to take place in nucleic acids before eventually making their presence felt via proteins. And information at the DNA level is fairly removed from proteins, with lots of critical non-coding sequences, redundancy, and a fair degree of flexibility. It’s not necessarily obvious that learning the organization of a genome would help an AI system figure out how to make functional proteins.

But it now seems like using bacterial genomes for the training can help develop a system that can predict proteins, some of which don’t look like anything we’ve ever seen before.

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A young woolly mammoth now known as Yuka was frozen in the Siberian permafrost for about 40,000 years before it was discovered by local tusk hunters in 2010. The hunters soon handed it over to scientists, who were excited to see its exquisite level of preservation, with skin, muscle tissue, and even reddish hair intact. Later research showed that, while full cloning was impossible, Yuka’s DNA was in such good condition that some cell nuclei could even begin limited activity when placed inside mouse eggs.

Now, a team has successfully sequenced Yuka’s RNA—a feat many researchers once thought impossible. Researchers at Stockholm University carefully ground up bits of muscle and other tissue from Yuka and nine other woolly mammoths, then used special chemical treatments to pull out any remaining RNA fragments, which are normally thought to be much too fragile to survive even a few hours after an organism has died. Scientists go to great lengths to extract RNA even from fresh samples, and most previous attempts with very old specimens have either failed or been contaminated.

A different view

The team used RNA-handling methods adapted for ancient, fragmented molecules. Their scientific séance allowed them to explore information that had never been accessible before, including which genes were active when Yuka died. In the creature’s final panicked moments, its muscles were tensing and its cells were signaling distress—perhaps unsurprising since Yuka is thought to have died as a result of a cave lion attack.

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