1 Flashcards
What is the primary aim of conservation biology?
To conserve and protect life on earth, including biological diversity—not just species or population numbers
Why is conservation biology not just about saving individual species?
Because species are part of a broader community and ecosystem, not isolated entities
Define “ecosystem” in the context of conservation biology
A community of different species interacting with one another and with the chemical and physical non-living environment
What are the three major goals of conservation biology?
- Document the full range of biodiversity on earth
- Investigate human impacts on biodiversity
- Develop approaches to prevent extinction and restore ecosystem function
What ethical principles guide conservation biology?
- Preserve species and ecosystem diversity
- Prevent untimely extinctions
- Maintain ecological complexity
- Allow evolution to continue
- Acknowledge biodiversity’s intrinsic value
How does conservation biology differ from other biological sciences?
It’s a crisis discipline that often requires action before all facts are known, combining science with an element of art
What two types of scale must conservation biology consider?
Time and space
How long did chemical evolution take before biological evolution began?
About 1 billion years.
What marks the beginning of biological evolution?
The formation of the first cells around 3.7 billion years ago.
What are the three necessary conditions for natural selection to occur?
- Genetic variability
- Traits must be heritable
- Traits must lead to differential reproduction
What is an adaptive trait?
A heritable trait that improves an organism’s survival and reproductive success under current environmental conditions.
What are the three levels of biodiversity?
- Genetic diversity within species
- Species diversity within an ecosystem
- Ecosystem diversity within a region
What is the Morphospecies concept?
A species is defined by morphological, physiological, or biochemical distinctness; it’s easy to apply but not always biologically accurate.
Define the Biological Species Concept.
A species is a group that can interbreed in the wild and is reproductively isolated from other groups.
What is the Evolutionary Species Concept?
A species is defined based on evolutionary relationships and the parsimony of evolutionary hypotheses.
Why is the term “species” problematic for microbes?
Because microbial classification often relies on genetic data rather than observable traits.
What are two key types of evolutionary change leading to new species?
Phyletic evolution (Anagenesis)
Branching evolution (Cladogenesis)
What is adaptive radiation?
The diversification of a species into multiple forms that occupy different ecological niches, such as the Hawaiian honeycreepers.
What does genetic diversity refer to?
The variation in genes and alleles among individuals within a population.
What determines the amount of genetic variation in a population?
The number of polymorphic genes
The number of alleles per gene
What are the three types of natural selection in populations?
Stabilizing selection
Disruptive selection
Directional selection
How does stabilizing selection affect a population?
It reduces genetic diversity by favoring intermediate traits.
What is directional selection?
Selection that favors one extreme phenotype, causing allele frequencies to shift in one direction.
