Gray Meeghan E
Program in Ecology, Evolution and Conservation Biology, University of Nevada, Reno, NV 89557, USA.
Biol Lett. 2009 Feb 23;5(1):23-5. doi: 10.1098/rsbl.2008.0571.
Infanticide by adult males occurs in a variety of species. While infanticidal attacks have been documented in several equid species in captivity, it has never been witnessed in free-roaming feral horses. I report an infanticide attempt by a free-living feral stallion on a recently born female foal. The stallion picked up the foal by the shoulders, tossed it around twice and bit in on the neck several times. The dam of the foal charged the stallion and successfully protected her foal from additional attacks. The foal survived the attack and later weaned successfully. The stallion recently took over the band and was excluded as the sire through genetic analysis. While this type of attack is rare, this case lends support to the sexual selection hypothesis and further demonstrates that equids have evolved with the risk of infanticide. Furthermore, it shows that maternal protectiveness can be successful against attacks by infanticidal males.
成年雄性动物杀婴现象在多种物种中都有发生。虽然在圈养的几种马科动物中已记录到杀婴攻击行为,但在自由放养的野马中从未目睹过。我报告了一匹自由生活的野生种马对一匹刚出生的雌性小马驹的杀婴企图。这匹种马咬住小马驹的肩部将其叼起,抛甩了两下,还多次咬其颈部。小马驹的母亲冲向种马,成功保护了自己的小马驹免受进一步攻击。小马驹在这次攻击中幸存下来,后来成功断奶。这匹种马最近接管了这个马群,通过基因分析被排除是小马驹的父亲。虽然这种攻击行为很罕见,但这个案例为性选择假说提供了支持,并进一步证明马科动物在进化过程中面临着杀婴风险。此外,它表明母性保护能够成功抵御杀婴雄性的攻击。