14. Evolution of the Brain and Behavior

Question 1

Brainstem

Answer 1

The part of the brain that controls basal metabolic rates, respiration, pulse, and other basic functions.

Question 2

Cerebellum

Answer 2

The “little brain” tucked under the cerebrum and important in the control of balance, posture, and voluntary movement.

Question 3

Cerebrum

Answer 3

The largest part of the human brain, which is split into left and right hemispheres. Seat of all “higher” brain functions.

Question 4

Neuron

Answer 4

The basic cellular unit of the nervous system. A neuron consists of a cell body and specialized processes called dendrites (which receive inputs from other neurons) and axons (outgrowths through which neurons send impulses to other neurons).

Question 5

Sulci (sing., sulcus)

Answer 5

Grooves on the surface of the brain that divide the hemispheres into gyri.

Question 6

Gyri (sing., gyrus)

Answer 6

Ridges on the surface of the brain that are formed by sulci.

Question 7

Cerebral cortex

Answer 7

The layer of gray matter that covers the surface of the cerebral hemispheres, divided into functional regions that correspond to local patterns of neuronal organization.

Question 8

Myelin

Answer 8

Fatty substance that sheaths neuronal axons, facilitating the transmission of electrical impulses along those axons.

Question 9

Primary cortex

Answer 9

Regions of the cerebral cortex that are involved directly with motor control or sensory input.

Question 10

Association cortex

Answer 10

Parts of the cerebral cortex where inputs from primary motor and sensory cortex are processed.

Question 11

Encephalization quotient (EQ)

Answer 11

The ratio of the actual brain size of a species to its expected brain size based on a statistical regression of brain to body size based on a large number of species.

Question 12

Olfactory bulbs

Answer 12

Knob-like structures located on the underside of the frontal lobes, that form the termination of olfactory nerves running from the nasal region to the brain.

Question 13

Language

Answer 13

The unique system of communication used by members of the human species.

Question 14

Hyoid bone

Answer 14

A small “floating bone” in the front part of the throat that is held in place by muscles and ligaments.

Question 15

Evolutionary psychology

Answer 15

Approach to understanding the evolution of human behavior that emphasizes the selection of specific behavioral patterns in the context of the environment of evolutionary adaptedness.

Question 16

Environmental evolutionary adaptedness (EEA)

Answer 16

According to evolutionary psychologists, the critical period for understanding the selective forces that shape human behavior; exemplified by hunter-gatherer lifestyles of hominids before the advent of agriculture.

Question 17

Human evolutionary ecology

Answer 17

Approach to understanding the evolution of human behavior that attempts to explore ecological and demographic factors important in determining individuals reproductive success and fitness in a cultural context.

Question 18

Bridewealth

Answer 18

Payment offered by a man to the parents of a woman he wants to marry.

Question 19

Progesterone

Answer 19

A steroid hormone produced by the corpus luteum and the placenta that prepares the uterus for pregnancy and helps maintain pregnancy once fertilization has occurred.

Question 20

Testosterone

Answer 20

A steroid produced primarily in the testes and ovaries, and at a much higher level in men than in women. Responsible for the development of the male primary and secondary sexual characteristics. Strongly influences dominance and reproductive behavior.

Question 21

Intrabreeding

Answer 21

Mating between close relatives.

Question 22

Inbreeding depression

Answer 22

Lesser fitness of offspring of closely related individuals compared with the fitness of the offspring of less closely related individuals, caused largely by the expression of lethal or debilitating recessive alleles.

Question 23

Incest

Answer 23

A violation of cultural rules regulating mating behavior.