Second broods are usually laid in nesting territory of the first brood. Others brood their eggs and the larvae undergo metamorphosis before the eggs hatch. Pollen brought into the hive for feeding the brood is also stored. The larvae of Cyclotornidae parasitise first Homoptera and later ant brood. This is because female crabs brood fertilised eggs on their pleopods. Nurse bees have the ability to selectively transfer sterols to larvae through brood food. Summer floods can destroy nests or make fishing difficult, resulting in starvation of the brood. Females typically brood their eggs during this time, exhibiting defensive behavior against smaller predators. Colonies that do not feed on insects cease brood production entirely. Parental-care parasitism emphasizes the relationship between the host and the parasite in brood parasitism. However, some species do not brood their young, and instead have a free-swimming larval stage. Females may sometimes associate with two males and all three help in raising the brood. This has been interpreted as the earliest knowledge of brood parasitism. The queen usually nurses the first brood alone. This hypothesis revolves around host manipulations induced by behaviors of the brood parasite.