Biology HN- Evolution- Day 1

What is the definition of evolution?

The change in allele frequency within a population of organisms over time.

What is artificial selection?

Humans select useful traits and breed those animals or plants.

What is sexual selection?

Natural selection in which one sex prefers a certain trait in the opposite sex.

What does VISTA stand for in natural selection?

Variation, Inheritance, Selection, Time, Adaptation.

What does 'Variation' refer to in VISTA?

Different traits or alleles present in a population.

What does 'Inheritance' refer to in VISTA?

Traits passed on to the next generation through DNA.

What does 'Selection' refer to in VISTA?

Only individuals with the best fit traits survive and reproduce.

What does 'Time' refer to in VISTA?

Evolution occurs over many generations.

What does 'Adaptation' refer to in VISTA?

Traits that are helpful for survival and reproduction.

What is stabilizing selection?

Selection for average individuals, decreasing variation in the population.

Give an example of stabilizing selection.

Average-sized lizards are more likely to survive than larger or smaller lizards.

What is directional selection?

Selection for one of the extreme variations of a trait.

Give an example of directional selection.

Long-trunked elephants have a selective advantage over shorter-trunked elephants.

What is disruptive selection?

Selection for both extremes of a trait's variation, against average phenotypes.

Give an example of disruptive selection.

Limpets with white and dark shells are favored in environments with matching rocks.

What is speciation?

The evolution of a species when two populations can no longer mate to produce offspring.

What are two ways that can cause speciation?

Geographic isolation and reproductive isolation.

What is geographic isolation?

The physical separation of populations, such as by land or water barriers.

What is reproductive isolation?

Formerly interbreeding organisms cannot produce fertile offspring.

What are the three types of reproductive isolation?

Behavioral, temporal, and mechanical isolation.

What is gradualism in evolution?

Change in a population over time.

What is punctuated equilibrium?

Rapid change in a population caused by environmental factors.

What is the role of natural selection in evolution?

Individuals best fit to their environment are most likely to survive and reproduce.

What is the significance of allele frequency in evolution?

Changes in allele frequency can indicate evolutionary changes in a population.

What is an example of a trait that can be selected for in artificial selection?

Sweetness in corn or milk production in cows.

How does natural selection lead to adaptation?

Organisms develop traits that enhance their survival and reproductive success.

What is a niche in ecology?

The role that an organism plays in its ecosystem.

What happens to a population when environmental conditions change?

Natural selection may favor different traits, leading to evolution.

How do mutations contribute to evolution?

Mutations can create new traits that may be advantageous for survival.