apes unit 2

ecosystem diversity

the number of different habitats available in a given area

species diversity

The number of different species in an ecosystem and the balance or evenness of the population sizes of all species in the ecosystem

genetic diversity

how different the genes are of individuals within a population (group of the same species)

Richness ( r)

the total number of different species found in an ecosystem (High (r) is generally a good sign of ecosystem health (more species means more quality resources like H2O & soil))

evenness

a measure of how all of the individual organisms in an ecosystem are balanced between the different species (indicates if there are one or two dominant species, or if pop. sizes are well balanced)

genetic diversity

measure of how different the genomes (set of genes) are of the individuals within a population of a given species (The more genetic diversity in a population, the better the population can respond to the environment Stressors like drought, disease, or famine)

Bottleneck event

An environmental disturbance (natural disaster/human habitat destruction) that drastically reduces population size & kills organisms regardless of their genome

Inbreeding depression

When organisms mate with closely related “family” members. Leads to higher chance of offspring having harmful genetic mutations because they’re getting similar genotypes from both parents

resilience

The ability of an ecosystem to return to its original conditions after a major disturbance(wind storm, fire, flood, clear-cutting, etc.) (Higher species diversity = higher ecosystem resilience)

ecosystem services

Goods and services provided by natural ecosystems that are beneficial to humans(often monetarily of life-sustaining)

Provisioning ecosystem service

Goods taken directly from ecosystems or made from natural resources (wood, paper, food)

regulating ecosystem service

Natural ecosystems regulate climate/air quality, reducing storm damage & healthcare costs

supporting ecosystem service

Natural ecosystems support processes we do ourselves, making them cheaper & easier (bees pollinate crops)

cultural ecosystem service

money generated by recreation (parks, camping, tours) or scientific knowledge

Island biogeography

Study of ecological relationships & community structure on islands (Islands can be actual islands in a body of water or natural habitats surrounded by human developed land)

Two rules of island biogeography

The larger the island, the greater the ecosystem diversity and Islands closer to the “mainland” support more species

Ecological range of tolerance

Range of conditions such as temperature, salinity, pH, or sunlight that an organism can endure before injury or death results Species and individual organisms both have a range of tolerance for all the different environmental conditions of their habitat

Optimal range

range where organisms, survive, grow, and reproduce

Zone of physiological stress

range where organisms survive, but experience some stress such as infertility,lack of growth,decreased activity, etc.

Zone of intolerance

range where the organism will die Ex: thermal shock, suffocation, lack of food/water/oxygen

natural disturbances

A natural event that disrupts the structure and or function of an ecosystem Ex: Tornados, hurricanes, asteroids, forest fires, drought

periodic natural disturbances

occurs with regular frequency (ex: dry-wet seasons)

Episodic natural disturbances

occasional events with irregular frequency (ex: hurricanes, droughts, fires)

Random natural disturbances

no regular frequency (volcanoes, earthquakes, and asteroids)

adaption

a new trait that increases an organism’s fitness (ability to survive and reproduce)

genetic diversity exists because…

Random mutations while DNA is being copied create new traits Crossing over in parent chromosomes creates new combinations of genes and therefore traits.

Natural selection

organisms that are better adapted to their enviornment survive and reproduce more offspring

evolution

Individuals with adaptations pass them on to offspring & individuals without adaptations die off, which leads to the entire population having the adaptation over time

Selective pressure/force

the environmental condition that kills individuals without the adaptation

ecological succession

A series of predictable stages of growth that a forest goes through

Primary succession

starts from bare rock in an area with no previous soil formation. Moss & lichen spores carried by the wind grow directly on rocks, breaking them down to form soil

Secondary succession

Starts from already established soil, in an area where a disturbance (fire/tornado/human land clearing) cleared out the majority of plant life. Grasses, sedges, wildflowers, and berry bushes have seeds dispersed by wind or animal droppings

Stages of succession

Stages are characterized by which types of plant species dominate the ecosystem; different species are adapted to the conditions of the different stages

Pioneer/ early succession species

appear first, when the ground is simply bare rock, or bare soil after a disturbance. Characteristics: seeds spread by wind or animals,fast growing, tolerant of shallow soil and full sunlight Ex: moss,lichen (bare rock) | wildflowers, raspberries, grasses/sedges

Mid-successional specie

appear after pioneer species have helped develop deeper soil with more nutrients by their cycles of growth/death. Characteristics: relatively fast growing, larger plants that need deeper soils with more nutrients than pioneers, sun tolerant. Ex: shrubs, bushes, fast-growing trees like aspen, cherry, and pine

Late successional or climax community species

appear last, after soil is deepened and enriched with nutrients by cycles of growth and death by early & mid successional species. Characteristics: large, slow-growing trees that are tolerant of shade and require deep soils for large root networks. Ex: maples, oaks, other large trees