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Species & Populations with little genetic diversity are at risk for extinction. Why?.
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Species & Populations with little genetic diversity are at risk for extinction
Why? • Species that make up a population that are not genetically diverse are more susceptible to extinction because if their environment changes there is no room for survival of the fittest, just extinction, because they’re all genetically identical.
California Condors http://www.youtube.com/watch?v=zA0uLfNPyuU&feature=player_embedded
California Condors • Most Condors died from lead poisoning, poaching, and habitat lost, which left only the smaller birds that had higher immune systems and could adapt to newer immune systems • However females only lay a single egg every two years • Condors only begin to reproduce when they are 6-8 years old
Black-footed ferret http://www.youtube.com/watch?v=xjZwtD_OVzg&feature=player_embedded
Black-footed ferret • Ferrets died from fatal, non-native diseases, leaving the ones with resistance • Ferrets died from loss of prairie dog prey • Ferrets also died from heavy habitat loss • Ferrets were once declared extinct until a dog retrieved a dead ferret and were only a dozen at one point in time
Prairie chickens http://www.youtube.com/watch?feature=player_embedded&v=s2_wdMmEupQ
Prairie chickens • Prairie chickens are less diverse because droughts destroy their food and make it difficult to provide for their young chicks • Their chicks also have difficulty with the exact opposite natural threat, rains, which wreck havoc on chick survival • Only the best suited chicks for these natural threats survive • Prairie chickens are also threatened by heavy habitat loss, and avoid nesting because of poor habitat
Corn rust http://www.youtube.com/watch?v=38XomXO4Tog&feature=player_embedded
Corn rust • Corn rusts are a plant disease that destroys the plants; leaves, stems, fruits, and seeds • Its composed of tiny aeciospores which land on the corn producing pustules, or uredia • The fungi produce asexual spores which disperse by wind, water, or by insect vectors spreading the infection
Tasmanian Devil http://www.youtube.com/watch?v=SWu9zj0EzC8&feature=player_embedded
Tasmanian Devil • The Tasmanian devil faces an uphill against a contagious cancer called devil facial tumor disease • Tumors were located in one devil’s Schwann cell and has been passed along ever since threatening extinction in 30 years