586 to the rear of the female's storage organ before insemination (Simmons, 2001). Removal of old sperm prior to insemination also occurs in some beetles.

Hemocoelic Insemination. This most unusual form of insemination, used by Cimicoidea (Hemiptera) and Strepsiptera, refers to the injection of sperm into the body cavity of a female from which they migrate to specialized storage sites, conceptacula seminales (not homologous with the spermathecae of other Insecta), adjacent to the oviducts. Comparative studies of the phenomenon in Cimicoidea have led authors to propose a possible evolutionary sequence (Hinton, 1964; Carayon, 1966). Primitively, the penis is placed in the vagina but penetrates its wall, thereby injecting semen into the body cavity. At a more advanced stage, the penis penetrates the integument, though not at any predefined site, and sperm are still injected into the hemolymph. Next, the site of penetration becomes fixed, and beneath it a special structure, the spermalege, develops to receive sperm. However, the sperm must still migrate via the hemolymph to the conceptacula seminales. At the most advanced level, insemination into a spermalege occurs, and sperm move to the conceptacula along a solid core of cells. What is the functional significance of this arrangement? In all forms of hemocoelic insemination a proportion of the sperm are phagocytozed either by hemocytes or by cells of the spermalege. As a result, it has been suggested that in Cimicoidea hemocoelic insemination is a method of providing nutrients to the female, enabling her to survive for longer periods in the absence of suitable food. It should be remembered that many Cimicoidea are semiparasitic or parasitic, and the chances of locating a host are slight. Interestingly, some species are apparently homosexual; that is, males inseminate other males, enabling the recipients to resist starvation for longer periods, while reducing the donors' own viability, surely a truly noble and altruistic act!

Modulators of Female Behavior and Physiology. Included in the seminal fluid are chemicals secreted by the accessory glands (rarely other parts of the male reproductive system) that bring about profound changes in the postcopulatory behavior and physiology of the female (Gillott, 1988,2003; Wolfner, 1997,2002; Kubli, 2003). These changes work to ensure that the male sires at least a portion of the eggs laid They include induction of refractoriness (unwillingness of the female to remate), reduction in female attractiveness, plugging of the female reproductive tract, acceleration of egg development, stimulation of egg laying, and displacement or incapacitation of sperm from previous matings. Other suggested effects of the seminal fluid chemicals are modification of host-seeking behavior in bloodsucking species (which typically mate near or on the host), change in the female's circadian rhythmicity, and a decrease in the female's life span.

4.4. Postcopulatory Behavior

In many species characteristic behavior follows copulation. This may be a continuation of the events that occur during copulation, for example, antennation or palpation of the female by the male, or feeding by the female on special secretions (nuptial gifts) offered by the male. As a result of these actions, the female remains passive, enabling sperm to be evacuated from the spermatophore.

Postcopulatory mate guarding has also been identified in species belonging to many orders (Simmons, 2001). Its purpose is to ensure complete transfer of sperm or to enable the female to oviposit undisturbed. It includes both contact and non-contact forms of behavior. Two forms of contact guarding occur: continued genital contact, seen, for example, in some terrestrial bugs, phasmids, and tettigoniids; and mounting, when the male simply remains on the female, as in beetles, many pond skaters, some grasshoppers, and some flies. In non-contact guarding, seen in crickets, most odonates, and other flies, the male disengages 587

from the female but remains close by ready to repel other males. The duration and intensity

of postcopulatory mate guarding may vary even within a species, according to the intensity of competition from other males (Simmons, 2001).

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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