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|Jazyk:||Počet slov:||3 882|
|Referát vhodný pre:||Stredná odborná škola||Počet A4:||11.9|
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As we can see, the fungus ant relationship is a unique and complex system of controls and dependencies. So even though there is greater harvesting pressure on the outside of the fungus garden, the more the ants prune and eat the fungus, the more the fungus responds and produces nutrient staphylae.
Reproduction and the colony
The reproduction and initiation of a colony is very similar in all species of the Atta tribe. Mating season is usually around May or June but the environment at the time has a major influence on mating times. The reproduction process always begins with the nuptial flights (Holldobler & Wilson, 1994). “Some species such as Atta sexdens, hold the flights in the afternoon, while others such as Atta texdens of the southwest United States, conduct them in the darkness of night” (Holldobler & Wilson, 1994). While beating their wings, the heavy females meet and mate with as many as 5 or more male in succession. While in the air, each queen will receive 200 million or more sperm from her mates, who will die within a day or two. She stores the sperm in her spermatheca and it is there the sperm will die for up to 14 years which is the known maximum lifetime of a queen. Each sperm will be used individually to fertilize a single egg. A single queen can produce as many as 150 million daughters which are the majority of the workers. Some will turn into queens capable of founding a colony on their own. Others will arise from unfertilized eggs to become short-lived males. After a queen has successfully mated, she will descend to the ground and rakes off her wings at the base. Then she will dig a cylindrical hole about 30 cm deep where at the bottom she widens a room about 6 cm across. She then spits out the packet of fungus she stored in her pouch at the bottom of her mouth onto the floor so her garden can start. The she lays 3 to 6 eggs. The fungus grows and when she has laid more then 20 eggs she will put the eggs and the fungus together. All this time the queen is cultivating the fungus by herself. At regular intervals about an hour or two she takes a piece of fungus and defecates on it with a brown drop of fecal liquid. In about 40 to 60 days the first adult workers emerge (Holldobler & Wilson, 1994).
All during this time the queen survives on the energy obtained from the metabolic breakdown of the wing muscles and fat from her own body. Also at the beginning she eats up to 90% of her eggs. This puts a lot of pressure on the queen.