Download - Warm-up 2/21/12: What is the difference Biomagnification Bioaccumulation Get out your Projects!
What Are Native Species?
• Native species are those that normally live and thrive in a particular community. They occupy specific habitats and have specific niches in their native environment. They have natural predators that help to keep their populations in check.
What Are Non-Native Species?
• Species that migrate into an ecosystem or are deliberately or accidentally introduced into an ecosystem by humans.
What are Invasive Species?
• A species introduced into an environment that is able to outcompete and displace the native species
• http://www.youtube.com/watch?v=u9cmARsp-BE&feature=related
Africanized Honeybee (Killer Bees)• 1957 African honey be crossed with native
honey bee to produce an overly aggressive bee in Brazil which escaped.
• Displaced the native honeybee through competitive exclusion and migrated northward at a rate of 200 miles per year.
• Northward migratory rate slowing down due to climate (frost).
• Will global warming allow their migration to move northward over time?
• Problems: They are so aggressive, they not only out-compete native bee populations, but pose great health threats to humans.
Fire Ants
• Late 1930’s introduced by accident in Alabama in shiploads of lumber and cargo.
• Interspecific competition reduced native ant species by 90%!
• Fire ants are very aggressive and through direct combat reduced native species.
• Since there are no natural predators, they produced more colonies than native ants and increased their population density significantly in south.
Fire Ants
• Interference Competition – fire ants consumed food and invaded habitat of native ant species (competitive exclusion principle).
• They release sulfuric acid when they bite and can kill deer fawn, lizards, birds, livestock, pets, and human babies.
• Fire ants have invaded trucks and caused roadside accidents when drivers have been attacked.
• Chew through underground cables and disrupt electric and phone service and have started electrical fires in the south.
Fire Ants• They are pesticide resistant
(Directional Natural Selection of r-strategists)
• USDA (US Department of Agriculture) has introduced a non-native parasitic fly that deposits eggs on the fire ants. When the larvae develop, they eat the heads of the fire ant. CHAOS! $$$$$$$$
What does the Competitive Exclusion Principle Say?
• No two species can occupy the same “niche” at the same time.
• A “niche” is the role an organism plays in the Ecosystem. (It’s job!)
Article Jig Saw
• Each group will do a case study on a different invasive species.
• Job 1- read the article aloud- highlight important information
• Job 2- fill in the graphic organizer with information concerning your invasive
• Job 3- Take Cornell Notes on your article
• Job 4- Make note cards about your article
• Job 5- Create a graphical representation of your article