This is a video of a male and female zebrafish (Danio rerio) mating. The male (pink and slim) chases the female (black and white, round), then swims alongside her and triggers her to release her eggs into the water. The male releases his sperm into the water, and the sperm fertilize the eggs as they fall to the bottom of the tank. This is an example of external fertilization.
This video contains some slow motion video to allow you to see the fish more easily, music and sound effects when the female releases the eggs.
Filmed by Tessa Montague, PhD student in Molecular Biology at Harvard University.
