Apple released three computers bearing the Centris name: the Centris 610 (replacing the Macintosh IIsi) and Centris 650 (replacing the Macintosh IIci in form and the Quadra 700 in function), both of which were introduced in March 1993, and the Centris 660AV which followed in July. Apple also considered the Macintosh IIvx to be part of the Centris line. The IIvx was released in October of the previous year, but, according to Apple, their lawyers were unable to complete the trademark check on the "Centris" name in time for the IIvx's release.
There is a size correlation which determines whether males become patrollers or hoverers. Patrollers tend to be larger so that they can better protect and copulate with emerging females. Smaller males are usually unable to compete as well, and so have to make the best out of a bad situation; thus, they become hoverers. Each group has a different set of behaviors. The patrollers move over a large space containing many other patrollers. Usually, patrollers will frequent the same spots over the course of their lives. Since the area is so large, the cost to defend it against other patrollers would be much greater than the potential mating benefits, so the patrollers show very little territoriality. Patroller males will usually only fight when a breeding female is near. In contrast, each hoverer stakes out an area of about one meter in diameter. These areas don’t overlap with other hoverers. Any fast moving object (i.e. bee, dragonfly, leaf, etc.) that enters a territory will be quickly chased. The chase allows the male bee to determine if a female is unmated, or if an enemy male is in his territory. If it is a male bee, the territory owner will chase it out, but not beyond the boundary of the territory. What is interesting is that every day (or even every several hours) the territory holder will abandon the area to establish a new zone. Often the male will never return to the vacated area, and it will be taken over by another male. This shows that hoverers show a low site tendency but strong territoriality. A balanced ratio of patrollers to hoverers is maintained, and thus, this ratio is an evolutionary stable strategy. If more males become patrollers, then the hoverers will benefit from the reduced competition, and the hoverers' genes will spread until the stable ratio is returned to. The same thing will happen if more males become hoverers.
Four varieties of bacteria have been found in the bee bread of the larva: Bacillus circulans, B. coagulans, B. firmus, and B. megaterium. Only the Bacillus genus has been found in the samples taken. Together, these four species were able to hydrolyze starch, ferment glucose, convert nitrates to nitrites, and produce dihydroxyacetone from glycerol. This group of bacteria also lowers the pH of the bee bread. These functions serve not only to protect the larva from other bacteria, but they also digest complex molecules which allow the larva to easily absorb nutrients without expending a lot of energy. The bacteria, in turn, receive a supply of food which results in a mutualistic relationship.
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