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1,667 bytes added ,  00:30, May 17, 2007
Expanded - added section on bee genetics and bee decline
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'''Bees''' are a type of flying [[insect]] related to [[ant]]s and [[wasp]]s.  They are an important pollinator of [[flower]]ing [[plant]]s, and vital to commercial growers in the [[United States]].  Many species of bees produce [[honey]].  
 
'''Bees''' are a type of flying [[insect]] related to [[ant]]s and [[wasp]]s.  They are an important pollinator of [[flower]]ing [[plant]]s, and vital to commercial growers in the [[United States]].  Many species of bees produce [[honey]].  
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==Bee genetics==
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Unfertilized eggs laid by a queen bee contain 50% of her [[gene|genes]] in different combinations. These eggs develop into male bees (drones) that have one copy of each [[chromosome]]. All [[sperm]] produced by a drone are identical [[clone|clones]].
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Fertilized eggs laid by a queen bee develop into female bees (workers). These have two copies of each chromosome – one from the queen and one from the male who fertilized her.
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Queens mate with 10-20 drones, so bee colonies are a mixture of subfamilies with the same mother but different fathers.
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This means that workers in the same subfamily are related by 75% of their genes. They are therefore more closely related to their sisters than to their own offspring, who would only have 50% of their genes. This predisposes them to help raise their sisters or go with a new queen when she starts a new colony rather than seeking a mate.
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==Bee Decline==
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Because of their vital role as pollinators, bees are responsible for 15 to 30 percent of the food U.S. consumers eat. However, in recent years there has been a steep decline in the population of bees, and some scientists claim that unless this is arrested the supply of some fruits and vegetables may also decline. <ref> http://news.nationalgeographic.com/news/2004/10/1005_041005_honeybees.html </ref>
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This decline is considered to be the result of diseases such as the varroa mite and other parasites, and the widespread practice of spraying crops with pesticides. Some scientists have asserted that the increased use of genetically modified crops may have a role to play, but the evidence for that is not yet clear.
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==References==
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[[Category:Insects]]
 
[[Category:Insects]]
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