Evolution and Natural Selection

Question 1

Theory of Natural Selection (and steps)

Answer 1

• Developed by Charles Darwin
• Organisms that are best adapted to an environment survive and reproduce more than others

The four steps are…

• Overproduction
• Variation
• Competition
• Selection

Question 2

Overproduction

Answer 2

Each species produces more offspring that can survive.

Question 3

Variation (and its importance)

Answer 3

Each individual has a unique combination of inherited traits from their parents

• The more variation within a species, the more likely it will survive.
• The more variation of types of species in an habitat, the more likely at least some will survive in case of environmental changes.

Question 4

Competition

Answer 4

Individuals compete for limited resources:
- Food, water, space, mates

Natural selection occurs through “Survival of the fittest”
- Fittest is the ability to survive and reproduce.

Question 5

Selection

Answer 5

The individuals with the best traits or adaptations will survive and have the opportunity to pass on its traits to their offspring.

• Natural selection acts on the phenotype (physical appearance), not the genotype (genetic makeup)

Question 6

Natural Selection

Answer 6

The process by which organisms that can adapt to changes in their environment are able to survive and reproduce.

• Natural selection is not random. It occurs in response to environmental changes and results in adaptation by advantageous traits being passed on.

Question 7

Adaptations

Answer 7

Changes in structure or behavior of populations to become more suited to an environment through natural selection.

Question 8

Structural Adaptations

Answer 8

A trait in an organism’s body that helps it to survive in its environment (physical).

• Ex. Camouflage, specialized structures, body parts, etc…

Question 9

Behavioral Adaptations

Answer 9

An action an organism takes to help it survive in an environment.

• Ex. Group behavior, migration, hibernation, etc…
• Group behavior helps protect animals from predators, form hunting packs, and reproduce efficiently.

Question 10

Innate vs. Learned Behavior

Answer 10

Innate Behavior – A behavior that an organism is born with

Learned Behavior – A behavior that an organism acquires through experience, teaching, or practice.