Scientists are coming closer to understanding the evolutionary reason behind monogamy, with two new studies out Monday exploring different advantages of the practice that pairs mates for the long haul.
Scientists said Sunday they had discovered an unexpectedly large and active community of single-cell organisms living on the Pacific sea floor at the deepest site on Earth.
Biologists say the human hand is a wonder of evolution, providing dexterity that lets our species perform activities as diverse as bricklaying, writing, ice hockey and brain surgery.