APES Unit 2
Which ecosystem most likely experienced a recent population bottleneck?
Ecosystem A, because its low genetic diversity could have resulted from an event that reduced the variation in the gene pool; A population bottleneck occurs when a significant decrease in the population size reduces genetic variation within a population.
Which of the following ecosystem services is categorized as supporting?
Photosynthesis, nutrient cycling, and creation of soils are supporting services (services necessary for the production of the other ecosystem services).
Which of the following ecosystem services is categorized as regulating?
Pollination, decomposition, and water purification; Regulating services are benefits obtained from the regulation of ecosystem processes.
range of tolerance
Populations thrive within certain ranges of abiotic factors such as pH, temperature, light, amount of moisture, etc. (generalists have a broad range of tolerance and specialists have a narrow range)
Which of the following correctly describes the disruption of an ecosystem service by an anthropogenic activity?
Provisioning services are disrupted by increased combustion of fossil fuels, which leads to an increase in air pollution.
How could ecologists could determine when an ecosystem is approaching a climax community?
Record the number and type of producers present every year after the disturbance; A high number of late successional plant species would indicate that the ecosystem is approaching a climax community.
supporting services
Services necessary for all other ecosystem services to happen (pest control, pollination, water filtration)
Which of the following economic consequences to a provisioning ecosystem service will most likely result from increased global warming?
The collapse of local fisheries, because of the damage to coral reefs from ocean acidification; Many fish depend on coral reefs for habitat, and the carbon dioxide that largely causes anthropogenic global warming also causes ocean acidification, which does damage coral reefs.
Which of the following ecosystem services is categorized as cultural?
Recreation, education, and aesthetics are cultural services (nonmaterial benefits obtained from ecosystems).
examples of environmental stressors
poverty, pollution, crowding, noise, natural disasters
provisioning services
products obtained from ecosystems; goods from environment (food, raw materials, energy, genetic resources, medicines)
instrumental value
provisioning, regulating, support, and cultural
biodiversity
variety of life on earth
Based on the theory of island biogeography, which of the following would most likely experience the greatest decline of specialist species if an invasive species emigrated from the mainland?
A small island in close proximity to the mainland; Being close to the mainland increases immigration of species. A small island has fewer niches available and specialized food webs, which is most likely to cause substantial declines in specialist species.
climax community
A stable group of plants and animals that is the end result of the succession process
Which of the following is an example of an ecosystem service that would provide protection from a hurricane storm surge?
An intact coastal wetland; An intact coastal wetland or marsh would offer natural protection from a storm surge categorized under regulating ecosystem service.
An island off the coast of Africa contains a larger percentage of specialist species than generalist species. Which of the following describes the most immediate effect if an invasive generalist species is introduced to the island?
As competition for resources increases, the population size of the island's specialist species will decrease; The invasive generalist species would most likely outcompete the island's species for food and other resources, as these are extremely limited on islands and specialists can thrive in a narrow range of conditions.
natural causes for habitat change
competition, predation, limited resources, natural disasters
anthropogenic
derived from human activities
fitness
differential ability to survive and reproduce
What does a low habitat diversity indicate?
ecosystem most likely has a low number of specialist species and few species that utilize large territories; Having a limited number of different habitats would inhibit the survival of different types of specialist species and those that control large territories.
intermediate disturbance hypothesis
ecosystems require a certain level of disturbance for maximum health and diversity
common descent/descent with modification
every living species has descended, with changes, from other species over time (genes mutate, individuals survive and reproduce, populations evolve)
genetic diversity
genetic variation among individuals in a population (one species)
indicator species
give early warning signs of damage or danger to a community (ex birds, butterflies, amphibians)
primary succession
happens in a place with out any soil (ex side of a volcano, landslides, flooding); starts with the arrival of airborne pioneer species such as lichens that do not need soil to survive
secondary succession
happens in an area that already has soil (ex after a forest fire); occurs faster and has different primary species than primary succession
keystone species
have a larger impact on the community, if removed, than other species
specialists
live under a very narrow range of conditions or feed on one or a very small group of species (ex panda, bears, koalas, salamander)
intrinsic value
moral/spiritual/religious/philosophical
ecological succession
natural, gradual changes in the types of species that live in an area; the gradual replacement of one plant community by another through natural processes over time
cultural services
non-material benefits obtained from ecosystems (recreation and tourism, aesthetic value)
limiting factors
the environmental factor that is most often in short supply; even if all the other factors are optimum, it's the one most likely to regulate population growth
species diversity
the number of species in a region or habitat (in a community or ecosystem)
island biogeography
the study of the ecological relationships and distribution of organisms on islands, and of these organisms' community structures
Habitat/ecosystem diversity
the variety of habitats that exist within a given region)
theory of natural selection
1. there is a struggle for existence among organisms 2. there is physical and behavioral variation in living organisms (even within the species level) 3. organisms with higher fitness (more helpful adaptations) are more likely to survive 4. over time, a "natural selection" will ensure that certain characteristics appear more and more often as they are passed through generations; entire species can change over time in this way
species richness
number of total species
Which of the following ecosystem services is categorized as provisioning?
Wood fuel, medicine, and potable water are provisioning services (products obtained from ecosystems).
bottleneck effect
a drastic and sudden reduction in the size of a population leads to a change in the gene pool
diversity index
a mathematical formula that measures species diversity by taking into account richness, abundance, and evenness
resilience
ability and rate of an ecosystem to recover from a disturbance and return to its pre-disturbed state
resistance
ability to remain unchanged when being subjected to disturbance
species evenness
abundance of individuals within each species
adaptation
any behavioral or physical characteristic that increase fitness
regulating services
benefits obtained from environmental regulation of ecosystem processes; water, carbon, nitrogen, and phosphorous cycles (clean air, purifying water, controlling erosion, etc.)
generalists
can live under a wide range of biotic/abiotic conditions (ex deer, wolf, raccoon, human)