Induced abortion and social factors in wild horses

  title={Induced abortion and social factors in wild horses},
  author={Joel Berger},
  • J. Berger
  • Published 5 May 1983
  • Environmental Science, Biology
  • Nature
Much evidence now suggests that the postnatal killing of young in primates1–4 and carnivores5,6, and induced abortions in some rodents7–9, are evolved traits exerting strong selective pressures on adult male and female behaviour. Among ungulates it is perplexing that either no species have developed convergent tactics or that these behaviours are not reported, especially as ungulates have social systems similar to those of members of the above groups10,11. Only in captive horses (Equus caballus… 

Conditional fetal and infant killing by male baboons

The results provide strong evidence for the existence of both sexually selected feticide and infanticide in the population of male baboons of the Amboseli basin in Kenya, and indicate that feticides andinfanticide are conditional male behavioural strategies employed under particular circumstances.

Behavioral Factors Affecting Reproduction in Domestic Horses: Sociobiological Approach

Results of three consecutive studies considering infanticide as a male's reproductive strategy and a mare’s counter strategies against it are summarized to explain substantial part of the high incidence of domestic horse fetal loss.

A Bruce Effect in Wild Geladas

A strong Bruce effect is reported in a wild primate, the gelada (Theropithecus gelada), where female geladas terminate 80% of pregnancies in the weeks after a dominant male is replaced, and data on interbirth intervals suggest that pregnancy termination offers fitness benefits for females whose offspring would otherwise be susceptible to infanticide.

Male infanticide in captive plains zebra, Equus burchelli

It is suggested that captive plains zebra show the highest occurrence of infanticide reported among ungulates, as reported for horses, Equus caballus, and tested the following hypothesis.

Evidence of infanticide in the Cape mountain zebra (Equus zebra zebra)

An infanticide attempt is reported in Cape mountain zebra (Equus zebra zebra) and the injuries sustained by the foals are consistent withinfanticide-based injuries documented in other equids species, providing the most conclusive evidence to date that infanticides takes place within mountain zaffe.

Infanticide as sexual conflict: coevolution of male strategies and female counterstrategies.

  • R. Palombit
  • Biology, Psychology
    Cold Spring Harbor perspectives in biology
  • 2015
Two bodies of evidence addressing coevolved strategies of males and females are reviewed, providing compelling evidence of sexually antagonistic coevolution surrounding the phenomenon of infanticide.

The Bruce effect revisited: is pregnancy termination in female rodents an adaptation to ensure breeding success after male turnover in low densities?

It is shown that overwintered and primiparous females, the most abundant cohort during population lows in the increase phase of cyclic rodent populations, were more likely to delay births after turnover of the male than year-born and multiparous Female.



A block to pregnancy in the mouse caused by proximity of strange males.

  • H. M. Bruce
  • Biology
    Journal of reproduction and fertility
  • 1960
It is suggested that the presence of other females may even help towards stabilizing a pregnancy, and the histology of the ovaries from females having blocked pregnancies showed a varying degree of pituitary-gonadotrophin stimulation.

Infanticide and other reproductive strategies in the collared lemming, Dicrostonyx groenlandicus

Postparturition effects of unfamiliar males in the collared lemming (Dicrostonyx groenlandicus) are reported and the significance of these effects on reproductive strategies in this species is discussed.

Reproduction in the zebra mare Equus burchelli antiquorum from the Kruger National Park

Zebra mares are seasonally polyoestrous, with an average of 85 of all mating and foaling occurring during the wet summer months (October to March), and full reproductive capacity is attained at three years.


Introduction to Quantitative Genetics is an important book for professionals, as it gives an overview of quantitative genetics, its successes and its lacunae, by one of its preeminent investigators, and an excellent summary of the field, and a tribute to the achievements of a creative and far-thinking group of quantitative geneticists.

An introduction to behavioural ecology

This chapter discusses natural selection, Ecology and Behaviour Testing Hypotheses in Behavioural Ecology, and the design of Signals in Ecology and Evolution.

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Resume Dans la population equine de l‘ile de Shacklesford Banks au large de la cote est est USA, des changements majeurs de l'organisation sociale sont apparus. Au lieu de vivre classiquement en

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