The purpose of killer sperm

Email e. Killer sperm in nematode worms prevent cross-breeding between different species, according to a new study. Getting children flu shots is even more important this year. Science News. For instance, ducks don't have to contend with the diseases and predators that make life in the wild difficult. Volodymyr Krasyuk.

Rumored Sperm Killer: Smoking. Female factors can influence the result of sperm competition through a process known as "sperm choice". However, inbreeding avoidance mechanisms that operate subsequent to copulation are less well known. Males who have successfully courted a potential mate will attempt to keep them out of sight of other males before copulation. Get the truth about what really affects your fertility. Mate-guarding also exists in the fish species Neolamprologus pulcher , as some males try to "sneak" matings with females in the territory of other males.

For example, among primates, female gorillas are relatively monogamous, so gorillas have smaller testes than humans , which in turn have smaller testes than the highly promiscuous bonobos. Terlecki said. An adequate diet consisting of increased amounts of diet and sometimes more specific ratio in certain species will optimize sperm number and fertility. Inbreeding ordinarily has negative fitness consequences inbreeding depression , and as a result species have evolved mechanisms to avoid inbreeding.