Additional Panopto Lectures (Ch.1+2)
Allopatric Speciation
> Barrier creates separate evolutionary pathway. > Unable to interbreed. >Will change physically.
Rachel Carson
> Launched Political Environmental Movement in U.S. > Wrote "Silent Spring"
Management
> Maintain Ecosystem Health > Enhance diversity beyond natural communities.
Polyploidy
> Multiplication of the total number of chromosomes and cells present in Meiosis. > Polyploids aren't able to breed back to parent plant. > Majority of flowering plant species have evolved via polyploidy.
Sympatric Speciation
> New species arises within range of the ancestral species. >Commonly seen in plants via methods such as polyploidy.
Adaptive Radiation
> One species will occupy "empty niches" and rapidly evolve.
DDT
> Organochloride > Colorless, tasteless, crystalline structure. > Originally developed as an insecticide.
Speciation vs. Extinction
> Speciation: Relatively Slow > Extinction: Relatively Fast > Estimated extinction occurs 35 % higher than speciation.
Divergent Speciation
> When one spp. becomes 2 > "split in 2's"
"Silent Spring"
> Written in 1962. > Motivated legislation in U.S. to be passed regarding the use of DDT
Aldo Leopold
> Wrote the Sand County Almanac > Created the Land Ethic
US Public Lands
Greater out West than in East
Land Ethic
Humans are "apart of" the ecosystem not "apart from" the ecosystem.
Resource Conservation Ethic
The belief that people should maximize use of resources, based on the greatest good for everyone. > "greatest good, greatest#, greatest time" Legacy: Multiple Use Philosophy
Wisent
--> European bison having a smaller and higher head than the North American bison. -->Bison are NOT buffalo
European view of natural resources
--> Imperialistic + Anthropocentric --> Resource use unsustainable.
John Muir
--> founded Sierra Club in 1892; fought unsuccessfully to prevent the damming of the Hetch Hetchy Valley in Yosemite National Park. -->Created Preservationist Ethic
Gifford Pinchot
--> head of the U.S. Forest Service under Roosevelt, who believed that it was possible to make use of natural resources while conserving them. --> created the Resource Conservation Ethic.
Preservationist Ethic
--> the principle that natural areas have intrinsic value beyond material value. --> set aside areas from development.