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|Jazyk:||Počet slov:||3 882|
|Referát vhodný pre:||Stredná odborná škola||Počet A4:||11.9|
|Priemerná známka:||2.98||Rýchle čítanie:||19m 50s|
|Pomalé čítanie:||29m 45s|
Another is the temperature of the nest at the time the larva is growing up. Still another is he physical condition of the queen. If the mother ant is healthy, she produces secretions during most of the year that inhibit the larva from developing into queens [this is a reason why only older nests produce queens and males at the same time]. In this one category the mother deserves the name we have given her – queen, or ruler of the colony. She not only determines whether an offspring will be male or female, but also assigns caste to her daughters. Yet even here, the workers exercise a kind of ultimate, parliamentary control. They alone decide which of their growing brothers and sisters will live or die, and hence they determine the final size and composition of the colony (Holldobler & Wilson 1994).
The leaf-cutter ant has posed serious problems for evolutionists. For what is the advantage an individual ant gains in putting all her energy into the selfless tasks of a colony, from leaf-cutting to caring for the larva to fighting as a soldier – without ever having a chance to mate and produce offspring of her own? This question has led evolutionists to one of the secrets of the superorganism. “The ants’ success lies in the evolutionary concept of kin selection” (Hoyt 1996). This concept occurs when members of a species work for the survival of relatives – genes by descent from a common ancestor rather than for one’s survival of its own offspring (which is called individual selection). This is a very complicated process in which many people have devoted their lives to its study.
The gathering of food by the leaf cutting ants is a complex series of interactions and communication which I will discuss. The foraging for food first is started from the central nest. Special ants called scouts range off of ant trails in search of food for the nest and if they find food, they start to recruit workers to collect the resource. This sounds simple but the process is actually very complicated. Using Howard, Henneman, Cronin, Fox, and Hormig’s research (1996) I will explain the process. When a scout find a food source, the decision of whether or not to recruit workers is based on the location, quantity, and quality of the source. Also the scouts examine resource consistency such as protein, lipid or simple sugar content. If a scout finds a familiar resource, it will recruit workers faster then if it found an unfamiliar resource.