California two-spot octopuses learned to track prey they could see only as a mirror reflection, then moved toward the actual hidden location of the target rather than lunging at the glass. That ...

If you were to make a case for evidence of extraterrestrial life on Earth, you would probably use octopuses as an example.

Cleaner wrasse have revealed a remarkable new side of fish intelligence. Marked with fake parasites, they used mirrors to inspect and remove the spots—far faster than seen in earlier tests. Even more ...