Vocabulary and Definitions
This term means a slight difference in an inherited trait among individuals of a species.
Variation
Darwin observed that tortoises on different islands had different shell shapes, Why?
They adapted to be able to reach the food they needed on each island
Natural selection requires this, because it provides different traits that may be beneficial in changing environments.
Genetic Variation
This adaptation involves one species resembling another for protection.
Mimicry
This environmental factor influences natural selection when food is limited.
Limited food supply
This is the process where organisms with helpful variations survive longer and reproduce more.
Natural Selection
Finch beak shapes differed because these varied from island to island.
Food Sources
These two processes are the primary sources of genetic variation.
Mutation and Sexual Reproduction
These adaptations include color, shape, or physical structure.
Structural Adaptations
Natural selection is NOT random, even though these occur randomly.
Mutations (occur randomly)
This type of adaptation allows a species to blend into its environment.
Camouflage
Darwin studied these Pacific islands where each had different environments and species.
Galapagos Islands
A population is MOST likely to survive environmental change when it has this.
High Genetic Variation
These adaptations include behaviors like hunting at night.
Behavioral Adaptations
Selective breeding differs from natural selection because traits are chosen by this group.
Humans (selective breeding = human choices)
This person studies plants and animals by observing them.
Naturalist
Darwin used this type of bird to understand food‑source adaptation.
Finch
Helpful traits are passed on because organisms with those traits do this.
Survive Longer and Reproduce More
These adaptations include internal or biochemical changes such as hibernation.
Functional Adaptations
Organisms without helpful traits are less likely to do this, reducing their genes in future generations.
Reproduce less or fail to reproduce
This is the term for an inherited trait that increases an organism’s chance of surviving and reproducing.
Adaptation
The observation that tortoisess’ neck lengths differed helped Darwin understand this major concept.
Evolution by Natural Selection
Natural selection over many generations leads to this outcome: more kinds of organisms as traits accumulate.
Increase Diversity of Organisms
Camouflage helps natural selection by allowing organisms to do this long enough to reproduce.
Hide and Survive
When environmental pressures favor certain traits, this process changes the population over time.
Natural selection (environmental pressures change populations over time)