Lecture 14

the variety of living things in a given area

• 1. Genetic Diversity - Genetic variation within a species (variety of different versions of the same genes within a species)
• 2. Species Diversity - # of species
• 3. Species Richness - # of species in an area

genetically similar parents mate and produce inferior offspring

richness and complexity of a biological community (number of niches, trophic levels etc)

number/variety of ecosystems

• species richness increases toward the equator
• Some possible causes:
• High plant productivity: more niches = higher species coexistence
• Climate stability, no glaciation: more time for evolution/speciation
• Diverse habitats increase species diversity and evenness
• Tropical rainforests and drylands, ecotones
• Human disturbance can increase local habitat diversity

have a large number of endangered and threatened species; have a concentration of endemic species; used to prioritize conservation; 34 - most near equator

species that are unique to that location

• Food
• Wild species can improve food security
• Wild strains can provide disease resistance
• Potential new food crops
• Medicinal value
• Wild species produce $150 billion/year in pharmaceuticals
• Ecosystem services
• Intact ecosystems have increased stability and resilience, and can provide ecosystem services
• Purify air and water
• Detoxify wastes
• Stabilize climate, moderate floods, droughts, wind, temperatures
• Cycle nutrients and renew soil fertility
• Pollination

humans have emotional bond with other living things

• extinction
• Extirpation = the disappearance of a population from a given area, but not the entire species globally. This can lead to extinction

• H: Habitat destruction and fragmentation
• I: Invasive species
• P: Pollution
• P: Population pressure (human)
• O: Overharvesting

gradual, piecemeal degradation of habitat; continuous habitats are broken into patches

• Conservation biology is one of the few scientific fields that is explicitly goal-directed
• Aim of biological conservation is to prevent individual species (or entire communities) from becoming extinct
• Important concepts for conservation
• Conservation geneticists = study genetic attributes of organisms to infer the status of their populations

how small a population can become before it runs into problems

a network of subpopulations; important in fragmented habitats

• 1937
• primary US legislation for protecting biodiversity
• forbids the government and citizens from taking actions that destroy endangered species or their habitats
• forbids trade in products from endangered species

those likely to become endangered in the foreseeable future

one that is in danger of extinction throughout all or a significant portion of its range

• UN Convention on International Trade in Endangered Species of Wild Fauna and Flora
• protects endangered species by banning international transport of their body parts

• 3 Goals:
• 1. Conserve biodiversity
• 2. Use biodiversity in a sustainable manner
• 3. Ensure the fair distribution of biodiversity's benefits

[LOL - it is red] species facing high risks of extinction

individuals are bred and raised in zoos or other captive facilities with the intention of later re-introductions

an organism that serves as an index of ecosystem health; help to prioritize communities that need protection

a species that plays a critical role in a biological community that is out of proportion to its abundance; protecting this can protect the entire ecosystem

Interesting species used to motivate people to preserve communities and contribute to conservation → “charismatic megafauna”

Species which require large blocks of land → preserving the umbrella also preserves the entire community; are often large species

recent trend to protect entire system rather than single species

restores degrade areas to some semblance of their former condition

a conservation organization pays off a portion of a developing country’s international debt

conservation organizations pay nations to conserve and not sell resources

legal document between the land owner and a government or private agency; the owner retains property rights but agrees not to allow certain types of development