Evolution and Biodiversity Concepts

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Questions and Answers

Which type of symbiotic relationship benefits both organisms involved?

Commensalism

Parasitism

Mutualism (correct)

None of the above

What is primarily responsible for the recovery of an ecosystem after a disturbance?

Fragmentation

Persistence

Resilience (correct)

Resistance

What is the difference between primary and secondary ecological succession?

Primary occurs after minor disturbances; secondary after major ones.

Primary leads to climax communities; secondary does not.

Primary occurs without soil; secondary occurs with soil. (correct)

There is no significant difference.

Which law in the US is primarily focused on the protection of endangered species?

Endangered Species Act of 1973 Signup and view all the answers

What type of ecological service involves the regulation of climate and air quality?

Regulating service Signup and view all the answers

Why are island species often more prone to extinction?

Limited habitat space and resources Signup and view all the answers

Which of the following factors is NOT commonly associated with species depletions?

Overpopulation Signup and view all the answers

Which statement best describes the concept of anthropogenic activities?

Human-induced activities that impact the environment Signup and view all the answers

What are the three conditions required for natural selection to occur?

Variability in population, heritability of trait, and differential reproduction Signup and view all the answers

How does a population's reproductive capacity influence the speed of adaptation?

Greater reproductive capacity can increase the speed of adaptation. Signup and view all the answers

What is one reason many island species tend to evolve as specialists?

Limited resources and space promote specialization. Signup and view all the answers

What is meant by the term 'population bottleneck'?

A significant reduction in population size due to environmental factors. Signup and view all the answers

Which of the following best describes resource partitioning?

Different species evolve to utilize resources differently and reduce competition. Signup and view all the answers

What is a keystone species?

A species that significantly affects its ecosystem's structure and diversity. Signup and view all the answers

Which of the following best defines speciation?

Divergence of one species into two or more distinct species. Signup and view all the answers

What is the Theory of Island Biogeography concerned with?

The relationship between island size, distance from the mainland, and species diversity. Signup and view all the answers

Study Notes

Evolution and Biodiversity

Evolution: Change in the heritable characteristics of biological populations over successive generations.
Adaptation (adaptive trait): Inherited trait that enhances an organism's ability to survive and reproduce in a particular environment.
Selective pressure: Environmental factors that favor certain traits over others.
Natural selection conditions:
- Variability in population (random mutations).
- Heritability of traits (passed on to offspring).
- Differential reproduction (differences in survival/reproduction).
Misconceptions about evolution: Evolution is not goal-oriented, not about individuals improving, and not about perfect organisms; it's about populations adapting to environments.
Limitations to natural selection:
- Limited genetic variation within a population.
- Environmental change occurs too rapidly, or in unpredictable ways.
- Selection pressures may favour existing traits rather than novel ones.
Population reproductive capacity and adaptation: A species' reproductive rate can influence how quickly it adapts to environmental changes. Faster reproduction allows quicker responses to changed conditions.
Antibiotic resistance in bacteria: Mutations in bacteria can cause resistance to antibiotics, and these resistant traits are passed on with reproduction. The traits then become prevalent when they're beneficial in an environment experiencing antibiotics.
Divergence and speciation: Divergence leads to speciation. Divergence is an increase in genetic differences between populations to the point where their differences are big enough to be grouped into different species
Geographic and reproductive isolation: Physical barriers (geographic isolation) and inability to reproduce (reproductive isolation) contribute to speciation.
Plate tectonics and isolation: Continental movements can cause geographic isolation, leading to speciation.
Habitat and niche: Habitat is the place where an organism lives; niche is an organism's role in its environment, including its interactions.
Generalist vs. specialist species: Generalist species have broad niches (can utilize many resources). Specialists have narrow niches.
Island species & specialization: Islands often have specialized species. This is because they have limited resources and unique environments.
Genetic diversity, species diversity, and habitat diversity: Genetic diversity is the variety of genes within a species; species diversity is the variety of species in an area; habitat diversity is the variety of habitats in an area.
Species richness and species evenness: Species richness is the total number of species in a region; species evenness is the relative abundance of different species in an area.
Population Bottlenecking: A sharp reduction in population size can decrease genetic diversity and make populations less able to respond to environmental stressors.
Theory of Island Biogeography: Species diversity on an island depends on the island's size and distance from the mainland: larger islands closer to the mainland tend to have greater diversity.
Non-native (invasive) species: Species introduced to an area where they are not native.
Endemic species: Species found only in a specific geographic area.
Indicator species: Species that reflect the overall health of an ecosystem.
Keystone species: Species that have a disproportionately large impact on the environment relative to their abundance. Examples include apex predators, pollinators or seed dispersers.
Foundation species: Species that create or significantly modify habitats that benefit other species. Examples include corals and ecosystem engineers.
Trophic cascades: Change in populations at one trophic level that triggers changes in other trophic levels.
Invasive species characteristics: Fast reproduction, high dispersal ability, efficient resource utilization, and lack of natural predators.
Predation, competition (intraspecific/interspecific): Predation is the consumption of one organism by another. Competition is the struggle between organisms for shared resources.
Fundamental niche and realized niche: Fundamental niche is an organism's ideal niche; realized niche is the actual niche it occupies due to interactions with other species.
Resource partitioning: Species adapt to divide resources to reduce competition.
Symbiotic relationships (mutualism, commensalism, parasitism): Mutualism benefits both species; commensalism benefits one species, with no harm to the other; parasitism benefits one species, harming the other.
Ecological succession (primary/secondary): Succession is the gradual change in species composition of a community over time. Primary succession occurs on bare rock; secondary succession occurs on previously vegetated areas.
Succession trends: Increased plant size, diversity, and net primary productivity over time in succession.
Climax community, pioneer species, disturbance: Climax community is the stable community at the end of succession. Pioneer species are hardy, first-arriving species. Disturbances disrupt succession and create new opportunities.
Disturbance level and diversity: Intermediate levels of disturbance tend to foster greater biodiversity due to the existence of different habitats.
Ecosystem stability (resistance/resilience): Resistance is the ability to withstand a disturbance, while resilience is the ability to bounce back from a disturbance.
Importance of species preservation: Intrinsic value, ecological roles, potential benefits for human wellbeing (e.g., medicine, agriculture).
Ecological services: The benefits that humans derive from ecological processes. Supporting (nutrient cycling, primary productivity), provisioning (food, water, raw materials), regulating (climate regulation, disease control), and cultural (recreation, aesthetic value).
Anthropogenic activities: Human activities.
Disruption of ecosystem services: Anthropogenic activities can disrupt ecological processes, leading to economic and ecological consequences.
Bioremediation (phytoremediation): Using organisms (including plants) to remediate polluted environments.
Endangered vs. threatened species: Endangered species are at high risk of extinction; threatened species are likely to become endangered.
Causes of species depletions (HIPPCO): Habitat loss/fragmentation, Invasive species, Population size, Pollution, Climate Change, Overexploitation (or overharvesting).
Extinction-prone species characteristics: Limited geographic range, specialized diet or habitat, low reproductive rate.
Island species vulnerabilities: Limited genetic variation, small population size, dependence on specific resources, introduction of predators.
Top consumer vulnerabilities: Require large habitats, susceptible to biomagnification of toxins, supported by lots of lower trophic-level biomass.
US laws (Lacey Act, ESA): Lacey Act regulates wildlife trade; ESA protects endangered and threatened species.
CITES treaty: International agreement regulating the trade in endangered species.
Biomes and weather: Terrestrial biomes (tropical rainforest, tundra, etc.) are characterized by temperature, rainfall and vegetation. Temperature affects air's capacity to hold water vapor. Low-pressure zones typically correlate with rainy weather; high-pressure zones correlate with dry conditions. Hadley cell convection currents affect global weather patterns. Understanding major wind bands is critical when predicting weather events.

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Description

Explore the key concepts of evolution and biodiversity, including natural selection, adaptation, and selective pressure. Understand the misconceptions surrounding evolution and the limitations of natural selection. Test your knowledge of how populations change over time in response to environmental influences.