Life History and Habits

As the differences are so great, the life history and habits of Blattodea and Mantodea are described separately.

Blattodea. Cockroaches are mostly secretive, primarily nocturnal, typically ground-dwelling insects that hide by day in cracks and crevices, under stones, in rotting logs, among

158 decaying vegetation, etc. Some, however, live on foliage, etc. well above the ground and may

CHAPTER 7 be diurnal, even basking in the sun. Most species prefer a rather humid environment, though some are found in semidesert or even desert conditions and others in semiaquatic situations. A few live in caves, ants' nests, and similar places. Some species may be gregarious, insects at the same stage of development occupying the same hiding places and feeding together. Subsocial behavior occurs in a few species. Generally cockroaches are omnivorous but are rarely active predators. A few species feed on rotting wood, which is digested by symbiotic bacteria or protozoans in the cockroaches' gut. These microorganisms are very similar to those found in termites. However, it remains debatable whether these were inherited from a common ancestor or were originally in one of these groups, then transferred secondarily when members of one group preyed on members of the other (see Grandcolas and Deleporte, 1996).

Usually courtship precedes mating, which may take more than an hour to complete. The secretion of the male's tergal glands attracts the female into the appropriate position and serves as an aphrodisiac, allowing the male to mount and transfer a spermatophore. Surrounding the spermatophore produced by males of most Blattellidae is a layer of uric acid, which is subsequently eaten by the female and provides a source of nitrogen for use in ootheca construction. Cockroaches exhibit four types of reproductive strategy: (1) oviparity (all families except Blaberidae), the eggs being enclosed in a leathery or horny ootheca that may be seen protruding from a female's genital chamber prior to deposition; (2) false ovoviviparity (almost all Blaberidae and a few Blattellidae), the membranous ootheca being held internally within a brood sac during embryonic development; (3) true ovoviviparity (seen in only four genera of Blaberidae), in which an ootheca is not formed, the eggs passing directly from the oviduct into the brood sac where the embryonic development occurs; and (4) viviparity (known only in Diploptera punctata but probably occurs in other members of this genus), where the eggs are small and lack yolk, the embryos obtaining nourishment directly from secretions of the brood sac. Facultative parthenogenesis has been observed in some species, and obligate parthenogenesis occurs in Pycnoscelis surinamensis. Hatching from the ootheca requires collaborative effort on the part of the embryos, which swallow air, swell, and cause the ootheca to split open, the embryos escaping more or less synchronously. Larval development is often slow, taking up to a year and involving as many as 12 molts. Adults are frequently long-lived.

Mantodea. The life-style of mantids is in marked contrast with that of cockroaches. Mantids live a solitary, sometimes territorial existence, mostly in shrubs, trees, and other vegetation, where they wait motionless for the arrival of suitable prey, usually other insects, though anything of appropriate size is fair game. Occasionally, mantids will stalk their prey until they are within grasping distance. This is normally the situation with ground-living species (which are mostly found in arid regions).

Mating in mantids is sometimes risky for a male, as his partner, almost always larger, may regard him as being more desirable as a meal than as a lover! However, cannibalism of the male by the female, often seen in captivity, is probably rare under natural conditions. Eggs are laid in a mass of frothy material that hardens to form an ootheca. Usually this is attached to an object some distance from the ground, though a few species deposit the ootheca in the soil. Parental care of the eggs and even first-instar larvae is shown by females in a few species. Obligate parthenogenesis occurs, rarely, for example, in Brunneria borealis from the southern United States. As in cockroaches, the development time is rather long and there may be many molts.

Phylogeny and Classification

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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