This phenomenon occurs when two sperm fertilise a single egg, resulting in a mixture of male and female cells in the developing embryo ...

This video shows a male superb lyrebird mimicking a mobbing flock after an inspecting female leaves the male's display mound without copulating Disclaimer: AAAS and EurekAlert! are not responsible ...

The smallest is the two-inch-long bee hummingbird. Everything about the anatomy of a bird reflects its ability to fly. The wings, for example, are shaped to create lift. The leading edge is ...