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animals

evolution

Should Evolution Treat Our Microbes as Part of Us?

How does evolution select the fittest “individuals” when they are ecosystems made up of hosts and their microbiomes? Biologist debate the need to revise theories.

Abstractions blog

Complex Animals Led to More Oxygen, Says Maverick Theory

For decades, researchers have commonly assumed that higher oxygen levels led to the sudden diversification of animal life 540 million years ago. But one iconoclast argues the opposite: that new animal behaviors raised oxygen levels and remade the environment.

Illustration of life evolving to use oxygen
evolution

Oxygen and Stem Cells May Have Reshaped Early Complex Animals

An unlikely team offers a controversial hypothesis about what enabled animal life to get more complex during the Cambrian explosion.

Game Theory

Hunger Game: Is Honesty Between Animals Always the Best Policy?

Game theorists have developed a new model of communication among animals. It suggests evolution will produce a situation in which members of a species are honest most of the time, but not always.