APES unit 2

biodiversity

variety of life forms in an environment

genetic diversity

range of inherited traits within a species

high genetic diversity =

high resistance

species diversity

indicates the number of species in a region/habitat

high species diversity =

high resilience

ecosystem diversity

broad number of ecosystems in an area

high ecosystem diversity =

good overall health (high species and genetic diversity)

resistance

how well a population responds/adapts to environmental change

resilience

how well a population bounces back from environmental change

speciation

creation of a new species (1-3/year)

background extinction rate

average rate species go extinct (1-2/year) (natural extinction, not including human caused)

cause of buffaloes biological extinction

westward expansion

cause of peregrine falcon endangerment

DDT (mosquito killer) led to egg thinning

other examples of endangered or previously endangered animals due to human interaction

condors, snow leopards, west Indian manatees

HIPPCO— H

habitat destruction

HIPPCO— I

invasive species

HIPPCO— P

pollution

HIPPCO— P

population growth (humans)

HIPPCO— C

climate change

HIPPCO— O

over harvesting

species richness

# of species in a given area

species evenness

relative abundance (no dominating species)

high species evenness =

high biodiversity

provisioning services

physical things provided by the environment

provisioning service examples:

wood, water, food, coal

cultural services

non physical benefits provided by the environment

cultural service examples:

spiritual, educational, aesthetic, recreational, economical (ecotourism)

regulating services

processes in nature that humans CAN replicate with enough resources

regulating service examples:

pollination, decomposition, air/water filtration

support systems

fundamental processes in nature that humans CANNOT replicate

supporting service examples:

photosynthesis, soil formation

what are the ecosystem services

provisioning, cultural, regulating, supporting

what 2 factors affect species richness on islands?

distance from mainland and the size of the island

what does an islands distance from the mainland affect?

colonization rate

(further from the mainland, lower the colonization rate)

what does the size of an island affect?

extinction rate

(smaller the island, higher the extinction rate)

definition of an island

land separated from other land

(ex. dingo fence, mt Kilimanjaro, micro forests, etc)

range of tolerance

limits to the abiotic conditions an organism can endure before injury/death

fundamental niche

ideal abiotic conditions for an organism

realized niche

conditions in which an organism actually lives

fitness

ability to survive and reproduce

adaptions

traits that improve an individual’s fitness

examples of abiotic factors

temp, weather, acidity, sunlight, etc

in order to survive species will sacrifice ____ first

reproduction

examples of natural disruptions to ecosystems

fire, natural disasters, changing ocean levels, globally warming/cooling

intermediate disturbance hypothesis states …

a habitat with moderate disturbance = high biodiversity

(because both early and late succession species can survive)

natural selection

“survival of the fittest”

organisms with the more favorable traits will survive and pass those on leading to those traits becoming more common and fueling evolution

reproductive isolation happens when

populations diverge from original due to changes in environment

reproductive isolation

two populations can no longer reproduce with each other

allopatric speciation

populations divide due to a physical barrier

sympatric speciation

populations divide due to mutation or subtle behavioral changes, no physical barrier

ecological succession

the gradual and predictable change that an ecosystem experiences over time until it reaches stability

climax community

stable ecosystem, no changing of dominant species

primary succession occurs on…

and is caused by …

bare rock

volcanic eruptions and receding glaciers

the first species to inhabit an area

pioneer species

moss and lichen are important because they …

when they die, they decompose and help form soil (takes 100s-1000s of years)

process of primary succession

volcanic eruptions/receding glacier

bare rock

moss/lichen

grasses

shrubs/bushes

small trees

big trees

secondary succession occurs on…

and is caused by …

soil

fire, natural disasters

pioneer species—primary succession

moss and lichen

pioneer species—secondary succession

grasses and weeds

process of secondary succession

fire/natural disaster

soil

grasses

shrubs/bushes

small trees

big trees

aquatic succession

the gradual filling of a shallow lake or pond with sediments

keystone species

plays a vital role in its community, often controls # of other species in the ecosystem

(typically exist in LOW numbers, NOT the largest species or major energy producers)

example of keystone species

sea stars (they eat mussels and control their populations)

ecosystem engineers

create/maintain habitat for other species

example of ecosystem engineer

beavers, elephants

indicator species

reflects the wealth of its ecosystem

example of indicator species

amphibians (live in both water and land