APES Unit 2 - Biodiversity

What are the the three levels of biodiversity?

Ecosystem diversity, Species diversity, and Genetic diversity

Ecosystem Diversity

the variety of different habitats available in given area

Species Diversity

the number of different 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 are (group of the same species)

Describe how genetic diversity relates to environmental disruptions

Without genetic diversity, a population cannot evolve, and it cannot adapt to environmental change/disruptions

Species Richness

the total number of different species found in an ecosystem (good if high)

How does species richness relates to ecosystem resilience?

Greater biodiversity in ecosystems, species, and individuals leads to greater stability when it comes to environmental changes

how habitat loss impacts generalist and specialist species differently

Specialist species are more likely to suffer from habitat loss and disruption than generalist species

Resilience

the ability of an ecosystem to return to its original conditions after a major disturbance

Generalist Species

species with a broad ecological niche

Specialist Species

species with a narrow ecological niche

biodiversity hotspot

a biogeographic region with significant levels of biodiversity that is threatened by human habitation.

identify the four categories of ecosystem services

provisioning, regulating, supporting, and cultural

Provisioning

Goods taken directly from ecosystems or made from natural resources

Supporting

Natural ecosystems support processes we do ourselves, making them cheaper and easier

Regulating

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

Cultural

Money generated by recreation or scientific knowledge

provisioning disruption

overharvesting, water pollution, and clearing land for ag./urbanization

regulating disruption

deforestation

supporting disruption

pollinator habitat loss and filling in wetlands for development

cultural services

deforestation, pollution, urbanization

Island Biogeography

study of ecological relationships and community structure on islands

Why do islands further from the mainland have lower species richness than closer islands?

Closer islands can be colonized a lot easier and require a lot less energy and stamina

Why do smaller islands have lower species richness than larger islands.

Larger islands are able to support more total species because they have more resources and space

Colonization (in terms of island biogeography)

successful immigration where a population becomes integrated into an ecological community

Why do islands have more specialist species than generalist species?

because of the limited resources, such as food and territory, specialist species are able to stick to their specific resources and decrease competition

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

temperature, salinity, pH, and sunlight

Describe the relationship between genetic diversity and ecological range of tolerance.

genetic diversity allows organisms to adapt and evolve in a way that helps them survive through different ecological challenges (the more genetic diversity, the greater the ecological range of tolerance will be)

Ecological Tolerance

range of conditions such as temperature, salinity, pH, or sunlight that an organism can endure before injury or death results

Optinal Range (ecological tolerance)

range where organisms survive, grow, and reproduce

Zone of Physiological Stress (ecological tolerance)

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

Zone of Intolerance (ecological tolerance)

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

Identify THREE examples of natural ecosystem disruptions.

tornados, hurricanes, asteroids, forest fires, drought

Periodic Events

occurs with regular frequency (dry-wet seasons)

Episodic Events

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

Random Events

no regular frequency (ex: volcanoes, earthquakes, asteroids)

How has Earth's climate changed over geological time?

changes in orbit and tilt which causes ice ages and warmer periods

How has sea levels varied over geological time?

glacial ice on Earth melts and forms

Migration:

A movement from one or region to another

Why would a population migrate?

usually due to natural disruptions (ex: following rain patterns, moving further north as water temp warms, birds migration shifting due to insect hatching shifting)

Adaptation:

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

How do adaptations arise in a population?

genetic diversity or variability in genomes of the individuals that allow them to adapt to their surroundings overtime

Natural Selection:

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

Selective Force:

the environment condition that kills individuals without the adaptations (ex: dark moths blend in with the soot-covered bark of trees while light moths are spotted and eaten by predators, selected force is the soot)

How can environmental change lead to evolution or extinction of a species?

depending on a population's genetic diveristy, they will either be able to adapt to the change or be unable to adapt and end up dying out

Primary Succession:

occurs in an area that hasn't previously been colonized by plants (bare rock and soil)

Secondary Succession:

starts from already established soil, in an area where a disturbance (fire/tornado/human land clear) cleared out the majority of plant life

Keystone Species:

a species on which other species in an ecosystem largely depend, such that if it were removed the ecosystem would change drastically. (ex. Beavers are ecosystem engineers that dramatically reshape the physical environment around them. Without them and their dams, the environment would change drastically)

Indicator Species:

organism—often a microorganism or a plant—that serves as a measure of the environmental conditions that exist in a given locale

Pioneer Species:

appear first, when the ground is simply bare rock, or bare soil (soil only after a disturbance) (ex. moss, lichen, wildflowers, etc.)

Late-Successional or Climax Species:

appear last, after soil is deepened and enriched with nutrients by cycles of growth and death by early and mid successional species (ex. maples, oaks, and other large trees)

Phylogenesis:

the evolutionary development and diversification of a species or group of organisms, or of a particular feature of an organism.

Bottleneck Effect

Genetic drift resulting from the reduction of a population, typically by a natural disaster (ex. earthquakes, floods, fires)

Allopatric Speciation

when a species separates into two separate groups which are isolated from one another