Chapter 24 (Evolution by Natural Selection)

Question 1

acclimation

Answer 1

Gradual physiological adjustment of an organism to new environmental conditions that occur naturally or as part of a laboratory experiment.

Question 2

adaptation

Answer 2

Any heritable trait that increases the fitness of an individual with that trait, compared with individuals without that trait, in a particular environment.

Question 3

descent with modification

Answer 3

The phrase used by Darwin to describe his hypothesis of evolution by natural selection.

Question 4

developmental homology

Answer 4

A similarity in embryonic form, or in the fate of embryonic tissues, that is due to inheritance from a common ancestor.

Question 5

extant species

Answer 5

A species that is living today.

Question 6

extinct

Answer 6

Said of a species that has died out.

Question 7

fossil

Answer 7

Any trace of an organism that existed in the past. Includes tracks, burrows, fossilized bones, casts, etc.

Question 8

fossil record

Answer 8

All of the fossils that have been found anywhere on Earth and that have been formally described in the scientific literature.

Question 9

genetic correlation

Answer 9

A type of evolutionary constraint in which selection on one trait causes a change in another trait as well; may occur when the same gene(s) affect both traits.

Question 10

genetic homology

Answer 10

Similarities in DNA sequences or amino acid sequences that are due to inheritance from a common ancestor.

Question 11

geologic time scale

Answer 11

The sequence of eons, epochs, and periods used to describe the geologic history of Earth.

Question 12

homology

Answer 12

Similarity among organisms of different species due to their inheritance from a common ancestor. Features that exhibit such similarity (e.g., DNA sequences, proteins, body parts) are said to be homologous.

Question 13

morphology

Answer 13

The shape and appearance of an organism’s body and its component parts.

Question 14

natural experiment

Answer 14

A situation in which groups to be compared are created by an unplanned, natural change in conditions rather than by manipulation of conditions by researchers.

Question 15

natural selection

Answer 15

The process by which individuals with certain heritable traits tend to produce more surviving offspring than do individuals without those traits, often leading to a change in the genetic makeup of the population. A major mechanism of evolution.

Question 16

phylogeny

Answer 16

The evolutionary history of a group of organisms.

Question 17

population

Answer 17

A group of individuals of the same species living in the same geographic area at the same time.

Question 18

primate

Answer 18

The lineage of mammals that includes prosimians (lemurs, lorises, etc.), monkeys, and great apes (including humans).

Question 19

sedimentary rock

Answer 19

A type of rock formed by gradual accumulation of sediment, as in riverbeds and on the ocean floor. Most fossils are found in sedimentary rocks.

Question 20

structural homology

Answer 20

Similarities in organismal structures (e.g., limbs, shells, flowers) that are due to inheritance from a common ancestor.

Question 21

transitional feature

Answer 21

A trait that is intermediate between a condition observed in ancestral species and the condition observed in more derived species.

Question 22

tuberculosis

Answer 22

A disease of the lungs caused by infection with the bacterium Mycobacterium tuberculosis.

Question 23

vestigial trait

Answer 23

Any rudimentary structure of unknown or minimal function that is homologous to functioning structures in other species. Vestigial traits are thought to reflect evolutionary history.