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biology

Art for "Evolutionary Math and Just-So Stories"
insights puzzle

Evolutionary Math and Just-So Stories

Evolutionary stories like the grandmother hypothesis are easy to construct from mathematical models, but how well do they reflect reality?

Abstractions blog

How Insulin Helped Create Ant Societies

Evolution may have coopted an ancient metabolic mechanism to set social insects on the path toward one of the most puzzling behaviors found in nature.

Photo of Escherichia coli under a microscope
Abstractions blog

Swarming Bacteria Create an ‘Impossible’ Superfluid

Researchers explore a loophole that extracts useful energy from a fluid’s seemingly random motion. The secret? Sugar and asymmetry.

Illustration for "To Remember, the Brain Must Actively Forget"
neuroscience

To Remember, the Brain Must Actively Forget

Researchers find evidence that neural systems actively remove memories, suggesting that forgetting may be the default mode of the brain.

Abstractions blog

Why Nature Prefers Couples, Even for Yeast

Some species have the equivalent of many more than two sexes, but most do not. A new model suggests the reason depends on how often they mate.

Art for "To Make Sense of the Present, Brains May Predict the Future"
neuroscience

To Make Sense of the Present, Brains May Predict the Future

A controversial theory suggests that perception, motor control, memory and other brain functions all depend on comparisons between ongoing actual experiences and the brain’s modeled expectations.

Photo of Physarum Polycephalum
cognitive science

Slime Molds Remember — but Do They Learn?

Evidence mounts that organisms without nervous systems can in some sense learn and solve problems, but researchers disagree about whether this is “primitive cognition.”

Photo of an axolotl
developmental biology

Salamander’s Genome Guards Secrets of Limb Regrowth

With a fully sequenced genome in hand, scientists hope they are finally poised to learn how axolotls regenerate lost body parts.

Illustation for "The Slippery Math of Causation"
insights puzzle

Solution: ‘The Slippery Math of Causation’

The all-too-intuitive picture of a straight arrow going from cause to effect is far too simplistic to describe the real world.