lecture 4 Flashcards
Henry thoreau
advocate for nature and anti-materialism (1800s)
John Muir
Developed preservationist ethic (18-1900s)
preservationist ethic
natural areas have spiritual (intrinsic) values that surpass the material value obtained from their exploitation
Gilfford pinchot
developed resource conservation ethic (1900s)
Resource conservation ethic
proper use of natural resources that will further “the greatest good of the greatest number for the longest time” resources should not be wasted
Aldo Leopold
developed the land ethic (mid 1900’s)
Land ethic
human use of resources was a balancing act between exploitation over the land and preservation (integrated resource use into preservation ethic)
definition of conservation bio:
integrated multidisciplinary scientific field that recently emerged in response to the challenge of preserving the world’s biodiversity (not defined by discipline but by goals)
goals of cons bio
document full range of planets biodiversity, investigate human impacts of biodiversity, develop approaches to prevent extinctions, maintain genetic diversity, protect and restore ecosystems
soule’s ethical principles:
Biodiversity should be preserved,
species and population extinctions should be prevented,
ecological complexity should be maintained
>4 billion years of evolution should continue, populations should continue to evolve in nature
biodiversity has intrinsic value, independent of economic, scientific, or aesthetic values
stewardship
responsible use and protection of the environment
michael soule
1978 proposed interdisciplinary approach to conservation at 1st conference
1985 began to develop discipline
most serious aspect of biodiversity loss
extinction
extinct
no living member exists
extirpated
locally extinct
extinct in the wild
exists only in captivity
regionally extinct
extinct over large areas of former range, less common term
ecologically extinct
species exists at such small numbers that its influence on larger ecosystem is negligible
extant
living
how many mass extinctions?
5, we are maybe in 6th
drivers of 5 major extinctions
alternating glacier and inerglacial periods
global cooling and warming, asteroid
volcanoes , global warming, anoxia, asteroid
elevated atmospheric CO2, global warming, ocean acidification
asteroid impact, volcanism, ocean anoxia
why are we in the 6th mass extinction?
current extinction rates vastly exceed background rates, rates are increasing
marine conservation biology
newly distinct field, lags behind terrestrial cons bio by decades
knowledge gaps, mechanisms not understood
minimum viable population:
smallest population size that can exist without risk of extinction
