Evolution of the Brain

Question 1

Define evolution

Answer 1

the gradual change of a species

Question 2

Explain the theory of evolution by natural selection and the roles of Darwin and Wallace on developing the theory

Answer 2

Darwin and Wallace proposed evolution by natural selection, a theory that says evolution proceeds by differential success in reproduction. Darwin traveled South American and the Galapagos finding evidence in turtles and finches. Wallace got the idea while suffering fever, and focused study on importance of biogeography.

Question 3

Explain the 4 main observations on which Darwin based his hypothesis.

Answer 3

1. Reproduction will increase a population rapidly unless factors limit it
2. individuals of a species arent identical
3. some variation is inherited
4. not all offspring survive to reproduce

Question 4

Describe how variations, adaptations and sexual selections work together in the theory of evolution according to Darwin

Answer 4

Darwin inferred that variations affect the probability that they will survive and reproduce, and adaptations increase likelihood of offspring through sexual selection which is when each sex has anatomical and behavioral features that favor reproductive success.

Question 5

Define convergent evolution

Answer 5

shows similarities in behavior or structure among unrelated animals due to adaptations to similar environments

Question 6

Define homoplasy

Answer 6

resemblance between features due to convergent evolution

Question 7

Define homology

Answer 7

similarity based on common ancestry

Question 8

Define analogy

Answer 8

refers to similar function, a human hand and elephant truck have similar function even though they look different

Question 9

Define mutations

Answer 9

spontaneous changes in genes, a rapid form of evolution

Question 10

Define chromosomes

Answer 10

found in nucleus, carries genetic information

Question 11

Explain the basic concept of species classification

Answer 11

each species has 2 names

Question 12

explain what phylogeny and taxonomy are

Answer 12

phylogeny-evolutionary history of particular group of organisms-represented as family tree
taxonomy-the classification of organisms

Question 13

six reasons to study other species

Answer 13

outstanding features like sensory skills, convenience, comparison, preservation, economic importance, and treatment of disease

Question 14

explain the role of learning during evolution

Answer 14

ability to learn is an important adaptation in order to find food and avoid danger

Question 15

explain the brain and neural similarities between mammals

Answer 15

All mammals have similar types of neurons. Same basic structures and general patterns are shared among all mammals and they evolved from common ancestors, but the relative size and location are different

Question 16

describe the two methods used to study evolution of the brain

Answer 16

endocast (uses skull to make cast of brain) and living animals (allows for study of internal structure of brain)

Question 17

explain what the encephalization factor is

Answer 17

measure of brain size relative to body size

Question 18

explain the main factors on human brain evolution, such as the change of volume of specific areas, which areas evolved larger and the consequences of these enlarged areas in the stages of development

Answer 18

brain has become larger and cortex became enlarged to modern size by brain regions developing later, resulting in long gestation periods

Question 19

briefly describe the relationship between brain size evolution and traits (bipedalism, tools, teeth, etc.)

Answer 19

as brain and cortex size grew, the ability to use tools decreased and necessity for large jaws and teeth decreased

Question 20

cost and benefits of having large brains

Answer 20

benefits: increased survival and ability for group interaction
costs: long gestation period, prolonged dependence on parents, high metabolic cost, and more susceptible to mutation

Question 21

explain the role of the genes on having a large brain

Answer 21

a few crucial genes can have a great effect on development, and small changes in DNA can alter timing and location of gene expression

Question 22

explain the differences in skin color, facial features and stature of the human species

Answer 22

in response to climate conditions