Inbreeding avoidance in a poeciliid fish (Heterandria formosa)

A1 Originalartikel i en vetenskaplig tidskrift (referentgranskad)

Interna författare/redaktörer

Publikationens författare: Ala-Honkola O, Tuominen L, Lindström K
Förläggare: SPRINGER
Publiceringsår: 2010
Tidskrift: Behavioral Ecology and Sociobiology
Tidskriftsakronym: BEHAV ECOL SOCIOBIOL
Volym: 64
Nummer: 9
Artikelns första sida, sidnummer: 1403
Artikelns sista sida, sidnummer: 1414
Antal sidor: 12
ISSN: 0340-5443
eISSN: 1432-0762


Polyandry is hypothesized to give females an opportunity to avoid inbreeding through postcopulatory selection mechanisms if precopulatory inbreeding avoidance is not possible, for example, because of forced matings. Here, we report a postcopulatory, prefertilization, inbreeding avoidance mechanism in the least killifish, Heterandria formosa, a species in which males can force matings. Females had 50% less sperm in their oviducts and ovarian cavities after mating with a sibling compared to a mating with a nonsibling male. Neither sex showed inbreeding avoidance in a dichotomous precopulatory mate choice test or during mating trials. Females in this species invest substantially in each offspring after fertilization (matrotrophy), whereas males invest little more than sperm. Based on theory, females should therefore be more likely than males to avoid inbreeding in this species. We suggest that females do this by reducing the amount of sibling sperm in their reproductive system. However, the possibility that males invested more sperm to nonsiblings could not be ruled out. In a fertilization success experiment, the first male to mate with a female sired all the offspring in most cases, even if it was a sibling. However, large females were more likely to carry offspring of multiple males. Possibly female sperm storage sites were filled by the first male, and only large females had space for the second male's sperm.


Heterandria formosa, Inbreeding avoidance, Poeciliidae, Polyandry, Postcopulatory sexual selection, Precopulatory sexual selection

Senast uppdaterad 2020-20-01 vid 03:39