Natural Selection, Speciation & Conservation

What is evolution defined as in the context of allele frequencies?

Change in allele frequency of a population’s gene pool over generations.

Who proposed the theory of use and disuse and when?

Jean Baptiste Lamark in the 1800s.

What significant work did Charles Darwin publish in 1859?

The theory of natural selection, based on his observations of species like finches in the Galapagos Islands.

What is adaptive radiation?

The process by which organisms diversify rapidly to fill different environmental niches.

What is artificial selection?

A form of selection where humans choose desirable traits in organisms, such as selective breeding.

What is required for natural selection to occur?

Traits must be heritable, require reproduction, survival, and beneficial traits.

What is meant by 'fitness' in the context of natural selection?

Fitness refers to the ability to survive and reproduce.

What is gene flow?

The movement of organisms into or out of a population, altering the allele pool.

What does the Hardy-Weinberg Equilibrium demonstrate?

It serves as a null hypothesis for the conditions under which evolution does not occur.

What does 'p² + 2pq + q² = 1' represent in the Hardy-Weinberg equilibrium?

It describes the frequency of genotypes in a population.

What is heterozygous advantage?

A situation in which heterozygous individuals have a higher fitness than homozygous individuals, such as in sickle cell anemia carriers being immune to malaria.

What is speciation?

The process by which new species arise through isolation and time.

What type of isolation occurs in allopatric speciation?

Geographic isolation.

What are pre-reproductive barriers in speciation?

Factors that prevent different species from mating, such as ecological or temporal isolation.

What is hybrid viability?

The likelihood of hybrids living a long and healthy life, which can be low due to genetic incompatibility.

What is the significance of vestigial structures in species?

They provide evidence of common ancestry and show features that are no longer used.

What is the impact of habitat destruction on biodiversity?

It decreases biodiversity and increases the risk of extinction for species unable to adapt to changing conditions.

What role do keystone species play in ecosystems?

They affect the survival of many other species in the ecosystem, creating a cascade effect if they go extinct.

What is in-situ conservation?

Conservation efforts aimed at recovering species on-site, such as nature reserves.

What does EDGE of Existence refer to in conservation efforts?

It refers to species that are evolutionarily distinct and globally endangered.

What effects can invasive species have on native species?

They can outcompete native species for resources and disrupt local ecosystems.

What is a mass extinction event?

A significant and rapid decline in biodiversity, with five major events in Earth's history and a potential sixth ongoing.