A fin whale washed ashore in Anchorage and was left there for months. Then a self-described ‘wacko’ museum director made a plan

When a whale dies, its body descends to the bottom of the deep sea in a transformative phenomenon called a whale fall. A whale’s death jump-starts an explosion of life, enough to feed and sustain a deep-ocean ecosystem for decades.

There are a lot of ways whales can die. Migrating whales lose their way and, unable to find their way back from unfamiliar waters, are stranded. They can starve when prey disappears or fall to predators such as orcas. They become bycatch, tangled in fishing lines and nets. Mass whale deaths have been linked to marine heatwaves and the toxic algae blooms that follow.

Groundbreaking find makes compelling case that humans were lighting fires much earlier than originally believed

Humans mastered the art of creating fire 400,000 years ago, almost 350,000 years earlier than previously known, according to a groundbreaking discovery in a field in Suffolk.

It is known that humans used natural fire more than 1m years ago, but until now the earliest unambiguous example of humans lighting fires came from a site in northern France dating from 50,000 years ago.

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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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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