Biologists mapping the human microbiome expected to find new bacteria and viruses, not entities that slip through every familiar category of life. Yet that is what several research teams now say they ...

The legendary “Little Foot” fossil may be an entirely new human ancestor. An international team of scientists led by ...

Modern humans (Homo sapiens) are the sole surviving representatives of the human family tree, but we're the last sentence in an evolutionary story that began approximately 6 million years ago and ...

The question of what defines a species has vexed scientists across the ages, particularly in conservation, where decisions require a firm understanding of biodiversity. When you purchase through links ...