Scientists have long suspected that big brains come with an evolutionary price — but now they've published the first experimental evidence to support that suspicion, based on their efforts to breed ...

In a Swedish lab, Alexander Kotrschal has deliberately moulded the intelligence of small fish called guppies. From a starting population, he picked individuals with either unusually large or small ...

From our perspective, guppies lead simple lives—eating, reproducing, and, after a couple of years, dying. Apply a little evolutionary pressure, though, and they can evolve larger brains that make them ...

Minnows and guppies are expendable. But it’s the big fish that bring in the crowds. The post When the church, like an ...

The streams of Trinidad and Tobago are home to the most unexpected of landscape gardeners. They’re guppies – tiny and beautifully coloured fish, just an inch or so long. Without tools or plans, they ...

Trinidadian guppies behave like matadors, focusing a predator's point of attack before dodging away at the last moment, new research shows. Trinidadian guppies behave like matadors, focusing a ...