Transcript Invasive
Warm-up 2/21/12: What is the difference Biomagnification Bioaccumulation Get out your Projects! Essential Question • What happens when humans introduce a new species into an area? NON-NATIVE SPECIES A MODERN-DAY CAUSE OF COMPETITION AND EXTINCTION 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=u9cmA Rsp-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. Geographic Distribution of Africanized Honey Bees in USA 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! $$$$$$$$ Fire Ant Distribution in the USA (Degrees Celsius) 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 Important Information • • • • • Country of Origin Current Distribution Method of introduction Native Species it is affecting Method of control