Chapter 4: Mechanisms of Population Change

Question 1

Biological Species

Answer 1

A group of populations that can reproduce together.

Question 2

Mutation

Answer 2

Changes in the genetic material of an organism.

Question 3

Selective Advantage

Answer 3

A characteristic that improves an organisms chance of survival usually in a changing environment.

Question 4

Natural Selection

Answer 4

When the characteristics of a population change because individuals with certain inherited traits survive changing conditions and pass on their traits to their offspring.

Question 5

Selective Pressure

Answer 5

When environmental conditions select “for” certain characteristics of individuals and select “against” others.

Question 6

Variation

Answer 6

A visible or invisible difference in members of the same population.

Question 7

Theory of Evolution By Natural Selection

Answer 7

The theory of how species have changed, and continue to change, during Earths history as a result of natural selection.

Question 8

Paleontology

Answer 8

The study of ancient life through the examination of fossils.

Question 9

Inheritance of Acquired Characteristics

Answer 9

The theory that characteristics that you acquire during your lifetime will be passed on to your offspring.

Question 10

Fossil Record

Answer 10

Remains and traces of past life found in sedimentary rock, which reveals the history of life on Earth and the kinds of organisms that were alive in the past.

Question 11

Transitional Fossils

Answer 11

The remains of organisms that show links between groups of organisms.

Question 12

Biogeography

Answer 12

The study of the past and present geographical distribution of species.

Question 13

Homologous Structures

Answer 13

Body parts in different species that have the same evolutionary origin and structural elements, but may have a different function.

Question 14

Analogous Structures

Answer 14

Body parts in different species that similar function but evolved separately.

Question 15

Speciation

Answer 15

The formation of a new species.

Question 16

Geographical Barriers

Answer 16

A barrier that causes speciation by physically separating a population (mountains, rivers, islands).

Question 17

Biological Barriers

Answer 17

Factors that keep species reproductively isolated even when they exist in the same region (behaviours, bird mating calls).

Question 18

Adaptive Radiation

Answer 18

When an ancestral species has been split into a variety of species, all of which are differently adapted.

Question 19

Gradualism

Answer 19

The theory that change occurs slowly and steadily in a linear fashion, and that large changes occur through the accumulation of many small changes.

Question 20

Punctuated Equilibrium

Answer 20

The model that suggests that evolutionary history consists of long periods of stable equilibrium until divergence occurs.