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cold blood cold blood |
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smooth or slimy skin warty and dry skin |
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strong, long legs and stubby bodies with short webbed hind feet hind legs |
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two bulging eyes parotid glands behind eyes |
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lay eggs in clusters lay eggs in long chains |
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a group of frogs is called a group of toads is called |
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an
ARMY of frogs
a KNOT of toads |
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14 species in MN, |
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13 species in |
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MI |
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Anurans are a part of the planet’s
bio-diversity. |
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1) double life--amphibious |
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2) permeable skin |
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3) absorb and concentrate
toxins--biomagnification |
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Biomagnification: a process in which retained
substances become more concentrated with each link in the food chain |
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extra or missing limbs |
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branching limbs |
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spikes or protuberances |
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missing eyes |
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abnormal webbing |
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reproductive |
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digestive |
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urinary |
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genetic origins |
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parasite disruption of limb formation |
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chemical contamination |
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viruses |
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ultraviolet radiation |
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physical trauma (predation, |
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people) |
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agrochemicals |
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heavy metals |
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acid rain |
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chlorofluorocarbons (CFCs) |
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herbicides |
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Maneb-fungicide |
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pesticides |
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propylthiourea |
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fertilizers |
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applications of the herbicide atrazine have led
to egg mortality and tadpole deformities (Hazelwood 1970) |
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a concern during the past decade |
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frog declines widespread and well-documented |
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possible causes include habitat destruction,
increased UV radiation, and chemical contamination |
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Loss of habitat |
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from
filling in wetlands to create more farmland for crops, and to build more
houses and roads |
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Increasing ultraviolet radiation |
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Pollution by chemicals |
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Acid rain |
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Pathogens |
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Parasites |
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Introduction of non-native species |
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Notes
