Box 52 Nuptial feeding and other gifts

Feeding of the female by the male before, during, or after copulation has evolved independently in several different insect groups. From the female's perspective, feeding takes one of three forms:

1 receipt of nourishment from food collected, captured, or regurgitated by the male (Box 5.1); or

2 obtaining attractive chemicals (often a form of nourishment) from a glandular product (including the spermatophore) of the male; or

3 by cannibalization of males during or after copulation.

There is controversy concerning whether and how much the female typically benefits from such male-proffered gifts. In some instances nuptial gifts may exploit the sensory preferences of the female and provide little nutritional benefit, while luring the female to accept larger ejaculates or extra copulations, and thus allow male control of insemination. However, a meta-analysis showed that female lifetime egg and offspring production increased with mating rate in groups of insects that either used nuptial feeding or did not, but that egg production increased to a larger extent in insects using nuptial gifts, whereas increased mating rate tended to increase female longevity of insects with nuptial feeding but decrease longevity of species not using nuptial feeding. Thus there appears to be no negative effect of polyandry (mating of females with multiple males) on the female reproductive fitness of insects with nuptial feeding.

From the male's perspective, nuptial feeding may represent parental investment (provided that the male can be sure of his paternity), as it may increase the number or survival of the male's offspring indirectly via nutritional benefits to the female. Alternatively, courtship feeding may increase the male's fertilization success by preventing the female from interfering with sperm transfer and by inducing longer post-copulatory sexual refractory periods in females. These two hypotheses concerning the function of nuptial feeding are not necessarily mutually exclusive; their explanatory value appears to vary between insect groups and may depend, at least partly, on the nutritional status of the female at the time of mating. Studies of mating in Mecoptera, Orthoptera, and Mantodea exemplify the three nuptial feeding types seen in insects, and continuing research on these groups addresses the relative importance of the two main competing hypotheses that seek to explain the selective advantage of such feeding.

In some other insect orders, such as the Lepidoptera and Coleoptera, the female sometimes acquires metabolically essential substances or defensive chemicals from the male during copulation, but oral uptake by the female usually does not occur. The chemicals are transferred by the male with his ejaculate. Such nuptial gifts may function solely as a form of parental investment (as may be the case in puddling; see below) but may also be a form of male mating effort (Box 14.3).

Beekeeping for Beginners

Beekeeping for Beginners

The information in this book is useful to anyone wanting to start beekeeping as a hobby or a business. It was written for beginners. Those who have never looked into beekeeping, may not understand the meaning of the terminology used by people in the industry. We have tried to overcome the problem by giving explanations. We want you to be able to use this book as a guide in to beekeeping.

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