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Published byDominick Carroll Modified over 9 years ago
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Biodiversity at Risk Jan 5/6
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Welcome! Please turn in – “Benefits of Biodiversity” from last class – Alligator reading HW Please take your seat and get started on today’s warm-up
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Objective By the end of class, students will develop a classification system to organize the major causes of species extinction
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Agenda Intro to mass extinction Watch mass extinction video Endangered species safari Identify major causes of species extinction Deep look at two causes of species extinction – Biomagnification – Invasive Species Exit Ticket
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What does extinction mean?
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Mass Extinctions
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Mass Extinction 5 historic mass extinction events Caused by dramatic changes in climate
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Is this the sixth mass extinction? “Normal” rate of extinction = 9 vertebrate species per century How many vertebrate extinctions were observed in the past century?
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Sixth mass extinction video
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What are the direct causes of species extinction? Endangered species safari – You will have 25 minutes to research at least 10 critically endangered organisms 20 posted around the room Visit Wildscreen Arkive – www.arkive.org – Write down the threats that each organism faces – You will use your notes to create a list of major causes of extinction
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Causes of Extinction Review the causes of extinction you noted during endangered species safari Working with your elbow partner, come up with a list of 4 to 6 major causes of extinction
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Over-hunting
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Pollution
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Pollution is made worse through biomagnification Toxins get more concentrated as they move up the food chain Even if there are low levels of toxins in the environment, they can be quite concentrated in top predators
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Pollution is made worse through biomagnification
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Biomagnification Biomagnification video
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Biomagnification of the pesticide DDT caused the near-extinction of the bald eagle in the middle of the 20 th century
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DDT is soooo safe! – they said
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BUT… DDT is still used in other countries And it is still manufactured in the United States
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Biomagnification of toxins is still an issue here, too
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Invasive Species Any organism that is not native to an environment and causes harm
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Invasive Species Videos Informative Historical Comedic
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Exit ticket What are the major causes of extinctions? Turn in now – Warm-Up & Exit Ticket – Video questions – Next class: Invasive species
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