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Acevedo0

    Exhibit C: Chemicals.
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    So how can we find the culprits behind this disaster?
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    Disease parasites or starvation a typical crime scene.
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    Although humans may be the penguins' biggest threat.
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    Sadly, most of this decline is due to human activity.
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    This is despite penguins spending 75% of their lives at sea.
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    First, they're one of the few birds that can't fly.
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    But the chicken's greatest contribution to science is yet to come.
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    Around the same time the Egyptians were hatching eggs.
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    When a hen incubates her eggs naturally, she stops laying new ones.
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    The earliest domestic chickens date back at least 7,000 years.
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