How CRISPR records infections in chronological order

A bacterium's CRISPR can keep a timeline of past infections

Bacteria usually add new pieces of viral DNA to one end of their CRISPR array. Because the newest pieces are added in order, the array can preserve a genetic timeline of viruses the bacterium and its ancestors encountered.

COVID-19 was linked to extra loss in smell-related brain tissue

0.2%–2% more tissue

A study found that people infected with COVID-19 had more tissue loss in brain regions connected to smell than uninfected people; most infections were mild. The average overall brain effect was equivalent to at least one extra year of normal aging. Researchers do not know whether the changes are temporary or permanent.

An octopus can flash a warning without changing color

Under ⅓ Second

A blue-ringed octopus can reveal its brilliant blue warning rings in less than a third of a second. But it does not need to create new pigment. Tiny muscles uncover reflective structures that were hidden beneath its skin. The rings were there all along—the octopus simply switches them into view.

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How CRISPR records infections in chronological order

A bacterium's CRISPR can keep a timeline of past infections

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