chapter 11: Biodiversity Flashcards
genetic diversity
measures variety of different versions of same genes within a species
species diversity
measures number of different kinds of organisms within a community
ecological diversity
measures richness and complexity of a community
species richness
total number of species in a community
species evenness
relative abundance of individuals within each species
reproductive isolation
organisms that breed in nature and produce fertile offspring
phylogenetic species concept
emphasizes the branches on a taxonomic tree (cladistic relationships)
evolutionary species concept
defines species in terms of evolution and historic times
DNA sequencing and molecular techniques give insight to…
taxonomic and evolutionary relationships
genome
total DNA sequence that characterizes a species
how many species are there?
1.7 million identified, range 3-50 million total, 4-6 million just insects, 65% invertebrates
biodiversity hotspots
tropical rainforests and coral reefs, 34 total, (1.4% world’s land area) contain 75% of world’s most threatened mammals, birds and amphibians
food benefits of biodiversity
wild plants could provide new sources of food or more genetic diversity for existing crops
benefits of biodiversity medically
more than half all modern medicines contain some natural product from a wild species
biopiracy
resources often extracted without compensation or sharing profits or incentive to preserve native species
ecological benefits of biodiversity
soil formation, waste disposal, are and water purification, nutrient cycling, solar energy absorption, and biogeochemical and hydriological cycles all depend on biodiversity
aesthetic and cultural benefits biodiversity
hunting, fishing, camping, hiking, etc. americans spend $104 billion wildlife related activities every year, ecotourism important form of sustainable economic development, existence value
extinction
the elimination of species on earth, threat to biodiversity
natural extinction
in undisturbed ecosystems, the background rate appears to be one species per decade, threat to biodiversity
human impact on natural extinction rate
increased the rate by 100 to 1000 times, half of primates, one quarter of all bird species could go extinct within 50 years
HIPPO
human caused reduction in biodiversity, habitat destruction, invasive species, pollution, population, overharvesting
biggest reasons for increase in extinction
habitat loss due to conversion to forest farmland, cities; habitat is fragmented into small, scattered plots; due to mining,. dams, destructive fishing practices
invasive species
(intentionally or accidentally introduced) thrive in new territory where they are free of usual predators, diseases, or resource limitations, 50,000 non-native species are established in US and 4,500 are free-lining, 15% cause environmental damage
Invasive Species
Barred Owl, Eurasian Milfoil, Kudzu, Emerald Ash Borer, Bighead Carp, Chestnut Blight
Pollution
pesticides, lead
population
human population growth and resource use
overharvesting
passenger pigeon, all major fish expected to collapse within 50 years if current trends continue, bushmeat trade
endangered species management proved successful for…
white tailed deer, wild turkey, snowy egret
endangered species
considered in imminent danger of extinction
threatened species
likely to become endangered, at least locally, in the near future
vulnerable species
those that are naturally rare or have been locally depleted to a level that puts them at risk
endangered species act
regulates a wide range of activities involving endangered species: taking, selling, possessing, transporting, shipping, importing/exporting into US
USFWS
required to propose a recovery plan detailing the rebuilding of the species to sustainable levels, works with HCP with private landowners to make sure landowners do not harm endangered species
keystone species
species has major effect on other members of community (bison)
indicator species
tied to specific communities of successional stages (brook trout)
umbrella species
require large blocks of undisturbed habitat (northern spotted owl)
flagship species
attractive organisms to which people emotionally react (giant panda)
recovery successes
bald eagle, peregrine falcons, and whooping crane
private property
80% of habitats for more than half of all the listed endangered species
gap analysis
seeks out unprotected landscapes rich in species
Grumbine’s principles for habitat protection
protect enough habitat for viability of all native species, manage at regional scale large enough to accommodate natural disturbances, plan over a period of centuries for evolution of the ecosystem, all for human use at level that doesnt result in significant degradation
convention on international trade in endangered species (cities)
regulates trade in living specimens and products derived from listed species, currently lists 700 species threatened with extinction by international trade
captive breeding
breeding in zoos and botanical gardens are one method of saving threatened species, provide reintroduction programs, but many species do not reproduce in captivity
successful captive breed
NeNe, the hawaiian goose, and the white rhino
issues with captive breeding
limited space in zoos, natural habitat may disappear in the process of saving the species, continual inbreeding may lead to infertility and low infant survival
