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|Jazyk:||Počet slov:||3 882|
|Referát vhodný pre:||Stredná odborná škola||Počet A4:||11.9|
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The ant has a hard exoskeleton to which the muscles are attached. It also protects the internal organs. The main feature of the ant is its head. The large solders have huge serrated blades which they can have up to 0.5 cm space between the mandibles. The size range can be from 1/16 to ½ an inch depending on the type of species. The ants are divided up into three different types according to size. Minima (<5mm long), media (>5mm long) and soldiers (a distinct class with oversized head and mandibles and a total body length of more then 13mm) (Whitehouse & Jaffe 1996). The average worker leaf-cutter ant lives from 4-6 months (Howard, Henneman, Cronin, Fox, Hormig. 1996). The worker ants commonly perform superhuman feats. If we magnify the operation to human scale, so that an ant’s 6-millimeter length grows into a meter and a half, the forager runs along the trail for a distance of about 15 kilometers at a velocity of 26 kilometers an hour. Each successive mile (to convert to familiar Anglo-American sports distances) is covered in 3 minutes and 45 seconds, about the current human world record. The forager picks up a burden of 300 kilograms or more and speeds back to the nest at 24 kilometers an hour – hence 4 minute miles (Holldobler & Wilson, 1994).
The queen is the largest of the ants and can reach length larger than ½ an inch and her life span can be 10 years or more (Smith. 1997). The queen has wings and when she decides to leave the nest she carries a small pellet of mycelium (the fungus) in a special pocket on her head. When a new nest is found, the mycelium is used to start to grow food again. The colony growth is slow at first but soon proceeds rapidly and reaches maturity in about 5 years.
The Nests – Fungus garden
The nests of the leaf cutting ant can get up to 200 square meters in length and 6 meters deep. Up to 5 –8 million ants can live in one nest (Holldobler & Wilson, 1994). The ants nests have many entrances and exits which facilitate travel and air supply into and from the nest. Some underground pathways can reach up to 200 meters in length. The nest consist of many chambers--2000 in an average sized colony. Each chamber is 8 to 12 inches (200-300 mm) in diameter. Nest building raises a huge mound of soil. Ants constructing an average-sized mound carry 88 tons (80,000 kg) of soil to the surface (Fogel R. 1997). Under the ground there are many paths which lead to multiple cavities in which fungus gardens grow. The fungus garden is a spongy mass like a sponge with lots of spaces.