APES Unit 2- Biodiversity

Describe the three levels of biodiversity

Ecosystem diversity: the number of diff. habitats available in a given area

Species diversity: the number of diff. species in an ecosystem and the balance or evenness of the pop. sizes of all species in the ecosystem

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

Describe how genetic diversity relates to environmental disruptions

higher biodiversity leads to higher population health

Describe the three levels of biodiversity

Ecosystem diversity: the number of diff. habitats available in a given area

Species diversity: the number of diff. species in an ecosystem and the balance or evenness of the pop. sizes of all species in the ecosystem

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

Describe how genetic diversity relates to environmental disruptions

higher biodiversity leads to higher population health

Define species richness

the total number of different species found in an ecosystem

Describe how species richness relates to ecosystem resilience

High (r) is generally a good sign of ecosystem health (more species means more quality resources like H2O & soil)

Explain how habitat loss impacts generalist and specialist species differently

Generalist species can feed on a wide variety of things and thrive in various environments. Specialist species eat a limited diet and occupy a much narrower niche. Specialist species are more likely to suffer from habitat loss and disruption than generalist species. As a result, many specialist species are becoming threatened, endangered, and extinct due to human activities. In contrast, generalist species are becoming more common.

Identify the four categories of ecosystem services

provisioning, regulating, supporting, cultural

Describe each of the four categories of ecosystem services and provide an example

Provisioning: Goods taken directly from ecosystems or made from nat. resources (wood, paper, food)

Regulating: Nat. ecosystems regulate climate/air quality, reducing storm damage & healthcare costs

Supporting: Nat. ecosystems support processes we do ourselves, making them cheaper & easier(bees pollinate crops)

Cultural: Money generate by recreation (parks, camping, tours) or scientific knowledge

For each ecosystem service category, describe how an anthropogenic activity could disrupt that ecosystem service

Provisioning: Disrupted by overharvesting, water pollution, clearing land for ag/urbanization

Regulating: Disrupted by deforestation

Supporting: Disrupted by pollinator hab. loss & filling in wetlands for development

Cultural: Disrupted by deforestation, pollution, urbanization

Describe the theory of island biogeography

If the island is closer to the land there is more diversity.
If the island is bigger there is more diversity.

Explain why islands closer to the mainland have higher species richness than further islands

-Easier for colonizing organisms to get to island from mainland
-More colonizing organisms = more genetic diversity in new pop.

Define the term "colonization" as it relates to island biogeography

when an organism or group of organisms starts a population in a habitat where the species was not already present

Explain why islands have more specialist species than generalist species

Single colonizing species from mainland quickly evolves to many slightly different species to adapt to new island conditions

Identify three or four conditions for which organisms have a range of tolerance

pH, salinity, temperature, sunlight

Describe the relationship between genetic diversity and ecological range of tolerance

The more genetic diversity the greater the ecological range of tolerance will be since some individuals will have an extended range that is more fit for their ecosystem, which they will pass down. Less genetic diversity lessens the chance of this since there aren't as many opportunities.

Describe ecological tolerance

the range of tolerance that an organism can endure before injury or death,

Identify the three zones of ecological tolerance.

Optimal range, zones of physiological stress, and zone of intolerance

Describe what happens to an organism or what they experience in each zone of ecological tolerance

Optimal range: range where organisms survive, grow, and reproduce

Zones 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

Provide an example of a physiological stressor or impact an organism could experience in conditions outside of its range of tolerance

thermal shock, suffocation, lack of food/water/oxygen

Identify THREE examples of natural ecosystem disruptions

asteroids, forest fires, drought

Define periodic, episodic, and random events

-Periodic events happen at a regular frequency

-Episodic events are occasional and irregular

-Random events have no regular frequency.

Identify 2-3 reasons that earth's climate has changed over geological time

environmental disturbances such as drought, changes in the planet's orbit, melting of glacial ice

Describe why sea level has varied on earth over time

glacial ice on earth melts & forms

Describe migration

wildlife may migrate to a new habitat as the result of natural disruptions

Identify 3 reasons that a population would migrate

following rain patterns, reaching optimal temperatures, pursuing prey

Define adaptation

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

Describe how adaptations arise in a population

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

Define natural selection

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

Describe what a selective force is and provide an example

the environmental condition that kills individuals without the adaptation (hawks are a selective force of field mice)

Explain how environmental change can lead to evolution or extinction of a species

As environments change, different traits may become adaptations & old traits may become disadvantages

Describe primary and secondary succession

-Primary succession occurs when bare land, devoid of soil, is colonized by successive waves of living organisms.

-Secondary succession occurs when a disturbance destroys existing life in a habitat but leaves soil intact.

Define keystone species

a species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically.

Provide an example of a keystone species and explain the significance it has in its habitat

Bees have been declared the most important species on the planet, which comes as no surprise as they provide food and shelter to a humongous diversity of organisms. Bees make perfect examples of keystone species, they promote sustainability among ecosystems by cross-pollinating many different plant species.

Define an indicator species

An indicator species is an organism whose presence is a reflection of a specific environmental condition.

Describe what a pioneer species is

A pioneer species is a species that appears first when the soil is bare, or rock is bare.

Provide an example of a pioneer species

mowed grass

Describe what a late-successional or climax community is

appear last, after soil is deepened and enriched with nutrients by cycles of growth and death by early & mid successional species

Provide an example of a late-successional or climax species

large trees such as maples or oaks