position of employing all the techniques of science in their work. Many strict behaviorists had adopted a more comparative approach, even though, to some that meant merely adding mice to rat laboratories. Ethologists began to employ laboratory methods. Just when the dispute appeared to have been transcended and synthesis of the schools was expected to allow the values, ideas, and knowledge of both to enhance the total understanding of nature, another group, sociobiology, began to exert influence.
Sociobiology was triggered by Hamilton (1964) who argued that bee worker castes evolved because the altruistic behavior of the workers in raising their sisters was adaptive. The adaptive feature depended on the concept that bee males, or drones, are haploid with all sperm identical. Workers, according to Hamilton, share the same diploid mother and identical genes from a common father, giving workers more genes in common with sisters than workers would have with their own offspring. Workers, thus, contribute more of their genes to the next generation by raising sisters than they would by reproducing themselves.
The unit in evolution is the population, not the individual. Variation in the population, not individual genes, is the central feature of evolution. In the example used by Hamilton that established the foundation for sociobiology, the bees, individual queens fly about 2.5 kilometers from their hives to mate in the air with 6 to 8 drones per flight for typically two flights. Mating with as many as 14 drones is common with all sperm stored together in the queen’s spermatheca. In addition, although workers are coded by odor to prevent drifting into alien hives, drones drift freely from hive to hive throughout the spring and summer months. Thus, they mate with unrelated queens from hives distant from the drone’s origin. Finally, the newly mated queen returns to her original hive which is vacated by the former queen with her fission swarm. The remaining workers then proceed to tend and raise the next brood, which is the progeny of the new queen and completely unrelated father drones. Therefore, bees are not closely related to hive mates as Hamilton supposed. Rather, genetic traits and even bee races are greatly mixed to provide population variation in each hive, as observations by apiarists confirm.
Конец ознакомительного фрагмента.
Текст предоставлен ООО «ЛитРес».
Прочитайте эту книгу целиком, купив полную легальную версию на ЛитРес.
Безопасно оплатить книгу можно банковской картой Visa, MasterCard, Maestro, со счета мобильного телефона, с платежного терминала, в салоне МТС или Связной, через PayPal, WebMoney, Яндекс.Деньги, QIWI Кошелек, бонусными картами или другим удобным Вам способом.
