Bateman Principle
In reproductive biology, the Bateman principle is the theory put forward by AJ Bateman in 1948, according to which males compete for the favor of females and try to fertilize as many females as possible. He sees the main reason for this in the fact that the male gametes - the sperm - are smaller and more numerous than the female gametes. This explains his experimentally determined finding that the variance of the pairing- and reproductive success in males is greater than in females, i.e. the range of reproductive success within males is greater than in females. This means that males are exposed to greater selection pressure.
In the experiment from which Bateman deduced his theory in 1948, he brought four females and four males of a fruit fly species ( Drosophila melanogaster ) together. According to the current state of science, the statistical procedures that Bateman used for his conclusions are no longer considered sufficient.
Since there are some animal species to which this principle cannot be applied in this simple form, it was subsequently expanded and generalized, in particular by Robert Trivers . In 1972 Trivers made it clear that the gender-specific form of parental investment in the offspring - and not the gender per se or the gamete size - are decisive for whether an individual behaves in the classic sense male or female.
See also
literature
- Peter M. Kappeler: Behavioral Biology. Springer Verlag, Berlin 2008 (2nd edition), ISBN 3-540-68776-9 .
- AJ Bateman: Intra-sexual selection in Drosophila. In: The Journal of Heredity. 2: 349-368, Oxford University Press, 1948.
Individual evidence
- ^ Brian F. Snyder, Patricia Adair Gowaty: A Reappraisal of Bateman's classic study of intrasexual selection. In: evolution. 61: 2457-2468, 2007