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such as hangingflies and scorpionflies, go out and catch prey items to present to females, who then consume the item while their hind ends are occupied with mating. Acquiring the prey items can be risky, since they are mainly obtained from spider webs, and so in a few species of scorpionfly, males offer specially produced wads of saliva to females instead. As with the katydids, the larger the gift, the longer the female will remain paired with the male. Sometimes, however, a male will simply grab a female and attempt to mate with her without offering one of these so-called nuptial gifts. Females take a dim view of such forceful behavior and generally won't stay coupled for very long with a male arriving sans offering. They also may be able to control the rate at which sperm are delivered into their reproductive tract. A recent study of a scorpionfly native to the Caucasus region in Europe found that while gift-bearing male scorpionflies remained coupled to females only twice as long as males attempting to force copulations, they transferred almost eleven times more sperm.

Females can also eject sperm after mating. Male damselflies and dragonflies, like the scorpionflies, simply grab females and mate with them, often removing the sperm of previous mates using the scoops and spines mentioned earlier. Most scientists studying these insects had assumed that the females had little control over who fathered their offspring, but a recent study by Alex Córdoba-Aguilar from the Institute of Ecology at the Autonomous University of Mexico showed that the females might have the last word. Córdoba-Aguilar noted that in many damselfly species, females had much less sperm in their storage organs than was present in the male's ejaculate. In fact, they seemed to have discarded so much sperm that they lacked sufficient numbers to fertilize all of their eggs. This seemed puzzling, or as he put it, "If females are using such sperm for oviposition, females are bad sperm administrators." He then collected females during different stages of the mating process and measured the volume of sperm present in their reproductive tracts. Then he counted the number of eggs that were laid after the females had mated with one or more males. It seemed that the females were favoring some males' sperm over others by ejecting the less-preferred males' contributions, long after the male himself had departed.

Males do seem to engage in some extreme antics to ensure that their ejaculates are not only placed in the appropriate part of the female's reproductive tract, but will be used by the female in fertilizing her eggs. As part of his ongoing studies of the intricacies of animal genitalia, Eberhard has uncovered some pretty racy stuff. A 2006 paper on spider mating behavior by Eberhard and colleagues Alfredo Peretti and R. Daniel Briceño, published in the ordinarily staid journal Animal Behaviour, contains passages that sound like what would happen if Danielle Steel were an entomologist: "Males squeezed females rhythmically with their enlarged, powerful genitalia throughout copulation." The title of the paper is no less suggestive, containing the words copulatory dialogue, again something one imagines those in the adult film industry to have mastered. In the spider under consideration, a rather modest-looking species called the short-bodied cellar spider, females "sing" during mating by moving their pedipalps, small appendages near the jaws, and making a sound the authors describe as "resembling squeaking leather." (If there is such a thing as spider porn, this is it.) As in many insects and their relatives, females mate with more than one male, and in this case the females seem to regulate paternity according to the ability of the male to be in tune with their wants and desires, if suggesting that spiders possess such things isn't too much of a stretch. The males adjust those rhythmic squeezes according to the sounds produced by the females, and males that were more responsive to females ended up fathering a larger proportion of the offspring.

My, What Big