Biodiversity & Biogeography
Identify 2 factors that are used to measure species biodiversity.
species richness
relative abundance (species evenness)
What are the 3 categories that would be found on a range of tolerance graph?
optimal range
zone of physiological stress
zone of intolerance
Explain TWO factors that differentiate primary succession from secondary succession.
primary - no soil and takes longer to reach a climax community
List the 4 ecosystem services.
What are provisioning, cultural, supporting, and regulating services?
The term for human-caused disturbances.
What is anthropogenic?
According to the theory of island biogeography, what type of island would have the fewest number of different species?
Far from the mainland and small in size
What are THREE abiotic factors that a species might experience a range of tolerance for?
pH, sunlight, temperature
Propose a way in which a scientist could determine if an ecosystem was approaching a climax community.
Record the biodiversity present.
List 4 examples of a provisioning ecosystem service.
food
medicine
lumber
freshwater
What is an adaptation?
What is a trait that by random chance gives an individual a survival advantage in a specific environment. Over time, this trait will become more prevalent in the population as a whole.
Ecosystem A has 5 different species with the following abundances: A - 20%, B - 15%, C - 20%, D - 20%, and E 15%
Ecosystem B has 5 different species with the following abundances: A - 5% B - 25% C - 25%, D - 35%, and E 10%
Which has the higher biodiversity and why?
Ecosystem A
species richness is the same, but A has a more even distribution of each
An organism that can signal changes in its environment, and can be used to help assess the health of an ecosystem.
What is an indicator species?
Identify TWO examples of primary succession AND TWO examples of secondary succession.
primary - glacial retreat and volcanic eruption
secondary - forest fire and abandoned agricultural field
What are two examples of cultural services that a freshwater lake ecosystem provides?
recreation, tourism, mental health, spiritual health
Disturbances that occur at repeated intervals.
What are periodic?
Why is genetic diversity so important within a population of a particular species?
With higher genetic diversity, there is a higher chance that a favorable mutation will arise. This also increases the chances the population will be able to adapt and evolve in the event of a disturbance.
Explain how population fluctuates between the zones on a range of tolerance graph AND explain what that means for individual organisms.
Stress - survive (few individuals)
Intolerance - death (no individuals)
Describe how the introduction of different plant species impacts the formation of soil during primary succession.
Lichens create soil from breaking down rock, the decay of mosses creates a thin layer of soil with few nutrients. As grasses and flowers are introduced and decay more nutrients are added and soil eventually becomes thick enough to support trees.
What are 2 regulating services that a forest ecosystem provides?
climate regulation (absorbs carbon from the atmosphere)
soil formation
What is the difference between a generalist and a specialist species?
a generalist can survive a wide range of environmental conditions or eat a variety of food - a specialist can only survive in a very narrow range of conditions or only eats one type of food
This type of diversity allows a particular species to have a good chance of surviving a natural disruption IF the diversity is high.
What is genetic diversity.
graph must include the zones, title, axis labels and units, bell curve
Identify correlation between biomass, primary productivity, biodiversity and ecological succession AND explain why.
as succession progresses, all 3 increase
Increased species of plants (especially those larger in size) are more productive. This also supports more species of animals that can find habitats so the biodiversity and biomass go up as well.
growing - desert (decreased productivity and water supplles)
Describe the Milankovitch cycles. What characteristics are associated with a "glacial period".
Eccentricity - how round the orbit it
Obliquity - tilt of Earth's axis
Precession where Earth's axis is pointed.
Glacial = low eccentricity (almost a circle), low obliquity, large Earth-Sun distance in NH Summer.
Inter-glacial = high eccentricity (more oval), high obliquity, small Earth-Sun distance in NH Summer.