We watched the following PBS video on "Biological Invaders."
Quick Summary:
From southern India to South America, from Guam to the Great Lakes, a quiet but significant threat to ecological health and biodiversity
is outrunning all efforts to control it. Invasive species -- foreign
organisms taking up residence in ecosystems where they didn't evolve --
are decimating crops and displacing native populations, even loosing new
human diseases, and costing the world economy billions of dollars a
year.
The invasions haven't gotten wide attention until recently, and attempts to beat back the intruders have not met with great success. Finally, though, governments are starting to take notice and mount new efforts to combat the bioinvasion that has been spread by the surge in global commerce.
It's estimated that since Columbus, some 30,000 species of imported plants, animals, and microbes have taken hold in North America. In some cases, invasive species have been purposely introduced, and in many others they have stowed away in ballast water of ships, in crevices of airplanes, or aboard unsuspecting travelers.
Most of the time the foreign transplant doesn't gain a foothold in the new environment, but sometimes the organism has neither opponents nor predators and thrives in its new habitat. Examples include the zebra mussels that invaded the Great Lakes, fouling shipping and water systems; the pesticide-resistant whitefly in South America, capable of transmitting 60 kinds of plant viruses; and a comb jelly from the Americas that was accidentally released into the Black Sea, causing $350 million damage to fish stocks.
The invasions haven't gotten wide attention until recently, and attempts to beat back the intruders have not met with great success. Finally, though, governments are starting to take notice and mount new efforts to combat the bioinvasion that has been spread by the surge in global commerce.
It's estimated that since Columbus, some 30,000 species of imported plants, animals, and microbes have taken hold in North America. In some cases, invasive species have been purposely introduced, and in many others they have stowed away in ballast water of ships, in crevices of airplanes, or aboard unsuspecting travelers.
Most of the time the foreign transplant doesn't gain a foothold in the new environment, but sometimes the organism has neither opponents nor predators and thrives in its new habitat. Examples include the zebra mussels that invaded the Great Lakes, fouling shipping and water systems; the pesticide-resistant whitefly in South America, capable of transmitting 60 kinds of plant viruses; and a comb jelly from the Americas that was accidentally released into the Black Sea, causing $350 million damage to fish stocks.
I had the students work in small groups to chunk the information using a Jig Saw Protocol and then had them share the information in a Google Document with the entire class.
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