When intruding male lions take over a pride of females, they often kill most or all of the infants in the group. This reduces the time until the females are again sexually receptive. This infanticide has many consequences for the biology of lions. It may be the reason, for example, that female lions band together in groups in the first place (to be better able to repel invading males). The period after the takeover of a pride by a new group of males is an uncertain time, when the stability of the pride is unpredictable. As a result, we might predict that females will delay ovulation until this uncertainty has passed. A long-term project working on the lions of Serengeti, Tanzania, measured the time to reproduction of female lions after losing cubs to infanticide and compared this to the time to reproduction of females that had lost their cubs to accidents (Packer and Pusey 1983). The data are given below in days. Does infanticide lead to a different distribution of the delay to reproduction in females than when cubs die from other causes? The data are not normally distributed within groups, and we have been unable to find a transformation that makes them normal. Perform an appropriate statistical test.

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Accidental death: 110,110, 117,117, 133,133, 135,135, 140,140, 168,168, 171,171, 238,238, 255255