Brown, A. (1986). An experimental test of optimal outbreeding in the harpacticoid copepod Tigriopus californicus. M.S. Thesis, Oregon State University, Corvallis, Oregon, U.S.A. 44 pp.

79635

Brown, A.

1986

44 pp.

Publication

Available for editors  

Hypotheses concerning relative costs of inbreeding and outbreeding were evaluated for the harpacticoid copepod Tigriopus californicus, which inhabits high intertidal tidepools. Field studies indicate high variation in biotic and abiotic parameters among pools. These findings coupled with previous information about very low dispersal rates and local adaptations to individual pools suggest that outbreeding (matings between non-poolmates) could be detrimental due to the break-up of adaptive gene groups. To evaluate costs of inbreeding and outbreeding, number of offspring produced by and mate choice between three different types of pairs were measured in the lab. The pairs, in increasing probability of relatedness, were non-poolmates, poolmates, and siblings. More offspring were produced from poolmate matings than from sibling matings; however, there was no significant difference found between number of offspring produced from poolmate matings and non-poolmate matings. These experiments were carried through only one generation--had they been followed through subsequent generations, an intermediate level of re)atedness (such as between poolmates) may have been shown to produce optimal fitness. These results do, however, show significant costs of inbreeding. Laboratory mate choice did not reflect the fitness differences among matings; mates were chosen at random with respect to relationship. This apparently non-optimal behavior is evaluated. It is suggested that males may not take the time or be able to assess the relationship of available females. There is probably a potential scarcity of virgin females as a result of the fact that females mate only once but males can mate more than once. Such a scarcity may make it more important for males to guard any available immature female rather than choose an adult female of the ideal relatedness.

RIS (EndNote, Reference Manager, ProCite, RefWorks)
BibTex (BibDesk, LaTeX)

[Back to search]