Sperm competition, pregnancy initiation and litter size: influence of the amount of copulatory behaviour in Mongolian gerbils, Meriones unguiculatus

doi:10.1016/S0003-3472(05)80521-4

Animal Behaviour

Volume 40, Issue 3, September 1990, Pages 417-427

https://doi.org/10.1016/S0003-3472(05)80521-4 Get rights and content

Abstract

Mongolian gerbils live in cooperative pairs or family groups, but they mate promiscuously. To investigate the reproductive outcome of alternative male and female mating strategies a series of laboratory studies was carried out. The number of ejaculations received by postpartum or cyclic oestrous females, mating with one or two males, was controlled. The paternity of juveniles was determined by the genetic marker of coat colour morph. When presented with one male, 70% of the postpartum oestrous females delivered a litter following one ejaculatory series, whereas all females delivered following two or more. When females were presented with two males in succession, and there was only one ejaculatory series, 90% of the females in postpartum oestrus, but only 35% of the cyclic oestrous females delivered a litter. Whether the sire was the cage-mate of the female or a strange male had no effect. Litter size increased significantly, and its variance decreased, with the total number of ejaculatory series. When two males copulated with the same female, the male with relatively more ejaculatory series sired a larger proportion of the litter, irrespective of mating order. When two males were allowed the same number of ejaculatory series, there was a shift from first-male advantage, to no order effect, to last-male advantage following one, to two or three, to four or five ejaculatory series from each male. The relative reproductive outcome of the first male was influenced more by the copulatory effort of the second male than by his own effort. The consequences of number and mating order of sires for average litter size and paternity are analysed.

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Sperm competition, pregnancy initiation and litter size: influence of the amount of copulatory behaviour in Mongolian gerbils, Meriones unguiculatus

Abstract

Anim. Behav.

Anim. Behav.

Anim. Behav.

Physiol. Behav.

Horm Behav.

Anim. Behav.

Anim. Behav.

Anim. Behav.

Anim. Behav.

Anim. Behav.

Physiol. Behav.

Anim. Behav.

On the mechanisms of sexual behavior and their evolutionary constraints

Social and territorial behaviour in the Mongolian gerbil (Meriones unguiculatus) under seminatural conditions

Biol. Behav.

Incest avoidance and bonding between siblings in gerbils

Behav. Ecol. Sociobiol.

Alternative mating strategies in the Mongolian gerbil

Behaviour

Mammals of the Mongolian People's Republic

Trudy mongol'. Kom.

Sexual exhaustion and recovery in the male rat

Q. Jl exp. Psychol.

Occurrence of successful multiple inseminations of females in a natural population of deer mice (Peromyscus maniculatus)

Evolution

An exteroceptive block to pregnancy in the mouse

Nature, Lond.

Pre-copulatory and copulatory behaviour in relation to stages of the oestrus cycle in the female Mongolian gerbil

Behaviour

Lifespan ontogeny and breeding success in Mongolian gerbils

Lab. Anim.

The cost of mating

Am. Nat.