Podcast
Questions and Answers
What effect does inbreeding have on the expression of genes?
What effect does inbreeding have on the expression of genes?
- It reduces the chance of expressing rare genes.
- It only affects dominant genes.
- It increases the likelihood of expressing rare or recessive genes. (correct)
- It eliminates deleterious genes.
Which species faced a significant demographic bottleneck in the past?
Which species faced a significant demographic bottleneck in the past?
- Northern elephant seal
- Cheetah (correct)
- Barred owl
- Northern spotted owl
What is a metapopulation?
What is a metapopulation?
- A population that exclusively inhabits one habitat type.
- A population with no gene flow.
- A group of individuals that only reproduce among themselves.
- Several populations that have regular or occasional gene flow. (correct)
Which habitat type produces surplus individuals for migration in a metapopulation?
Which habitat type produces surplus individuals for migration in a metapopulation?
What is a significant result of the lack of genetic diversity in male cheetahs?
What is a significant result of the lack of genetic diversity in male cheetahs?
Why do northern elephant seals not seem to suffer from problems linked to genetic similarity?
Why do northern elephant seals not seem to suffer from problems linked to genetic similarity?
What is a primary factor conservation biologists consider for species survival?
What is a primary factor conservation biologists consider for species survival?
What characteristic defines a sink habitat for species like the spotted owl?
What characteristic defines a sink habitat for species like the spotted owl?
What does the equilibrium theory of island biogeography propose affects biodiversity on isolated islands?
What does the equilibrium theory of island biogeography propose affects biodiversity on isolated islands?
Which factor contributes to the higher extinction rates on small islands?
Which factor contributes to the higher extinction rates on small islands?
What term describes the stability in genetic variation within large populations?
What term describes the stability in genetic variation within large populations?
Which process accounts for the gradual changes in gene frequencies due to random events?
Which process accounts for the gradual changes in gene frequencies due to random events?
What is referred to as the founder effect in population genetics?
What is referred to as the founder effect in population genetics?
What could limit species adaptability and survival in small populations?
What could limit species adaptability and survival in small populations?
Which scenario best describes a demographic bottleneck?
Which scenario best describes a demographic bottleneck?
What is a significant concern for population biologists regarding island species like birds in Hawai’i?
What is a significant concern for population biologists regarding island species like birds in Hawai’i?
Flashcards
Biodiversity
Biodiversity
The number of species found in a particular area or habitat. It is usually measured as species richness (the total number of species) and species evenness (the relative abundance of each species).
Equilibrium Theory of Island Biogeography
Equilibrium Theory of Island Biogeography
A theory that explains how the number of species on an island is determined by a balance between the rates of immigration and extinction.
Colonization
Colonization
The process by which new species arrive on an island.
Extinction
Extinction
Signup and view all the flashcards
Hardy-Weinberg Principle
Hardy-Weinberg Principle
Signup and view all the flashcards
Genetic Drift
Genetic Drift
Signup and view all the flashcards
Founder Effect
Founder Effect
Signup and view all the flashcards
Demographic Bottleneck
Demographic Bottleneck
Signup and view all the flashcards
Inbreeding
Inbreeding
Signup and view all the flashcards
Bottleneck Effect
Bottleneck Effect
Signup and view all the flashcards
Metapopulation
Metapopulation
Signup and view all the flashcards
Source Habitat
Source Habitat
Signup and view all the flashcards
Sink Habitat
Sink Habitat
Signup and view all the flashcards
Minimum Viable Population Size
Minimum Viable Population Size
Signup and view all the flashcards
Study Notes
Island Biogeography and Biodiversity
-
Small, remote islands generally have lower biodiversity than larger islands.
-
MacArthur and Wilson's equilibrium theory links island diversity to colonization and extinction rates.
-
Colonization rates depend on proximity to source populations (e.g., continents, other islands).
-
Extinction rates depend on island size, which influences population size and vulnerability to environmental events.
Genetic Diversity in Small Populations
-
Genetic variation maintains stability in large, stable populations (Hardy-Weinberg principle).
-
Random environmental changes can cause shifts in gene frequencies (genetic drift).
-
Genetic drift becomes significant in isolated, small populations due to limited genetic variation.
-
Founder effect: Reduced genetic diversity from a small initial colonizing population.
-
Demographic bottleneck: Loss of genetic variation due to a catastrophic event.
-
Inbreeding: Mating of closely related individuals, increasing expression of recessive genes.
-
Genetic diversity loss can effect adaptability and reproduction for the species.
Cheetahs and Northern Elephant Seals
-
Cheetahs are a prime example of a species affected by genetic bottlenecks, with low fertility, abnormal sperm, and reduced offspring survival, due to nearly identical genetic make-up.
-
Northern elephant seals, despite near extinction, recovered and have almost identical genetic profiles.
-
The survival of these species can depend on selected populations who are the most fittest or where no harmful genes are present.
Minimum Viable Population Size
- Biologists use island biogeography principles to estimate minimum viable population size that is necessary for long-term survival in endangered species.
Metapopulations
-
A metapopulation is a group of populations across geographically separate areas that interact.
-
Gene flow between these groups is possible via corridors (migration routes).
-
Northern Spotted Owls are an example of organisms that have been historically interdependent.
-
"Source" habitats have higher birth rates than death rates and produce the individuals to migrate and populate other regions.
-
Habitats called “sink” regions have birth rates lower than death rates.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Description
Explore the concepts of island biogeography and genetic diversity in small populations. This quiz covers key theories such as MacArthur and Wilson's equilibrium theory, the Hardy-Weinberg principle, and factors affecting colonization and extinction rates. Test your knowledge on how these concepts interact to influence biodiversity.
