Here we report six cases of infanticide in the domestic cat directly observ
ed in papulations located in the rural environment. This is the first time
that infanticide in domestic cats has been witnessed directly and described
. All infanticidal males were fully adult and sexually mature unknown males
. All kittens killed were within their first week of life. The killing patt
ern was generally the same as that described in lions. All females reacted
aggressively but could not prevent the infanticide. Three hypotheses are di
scussed : (1) infanticide is a remnant of cat male reproductive strategy se
lected in the original environment; (2) the conditions of the rural environ
ment have created a selection pressure encouraging a polymorphism of infant
icidal and noninfanticidal males to evolve; (3) infanticide is an abnormal
behaviour caused by environmental conditions such as human disturbance. (C)
1999 Wiley-Liss, Inc.