Chapter 6: Evolution of the Brain and Behavior

Question 1

Evolution

Answer 1

Change in the properties of a species over generations.

Question 2

It was originally believed that each species was created ___.

Answer 2

Seperately

Question 3

Speciation

Answer 3

Development of new and separate species.

Question 4

Homology

Answer 4

Relationships among species; features are based on common ancestors.

Question 5

Paleontology

Answer 5

Suggested evolution
- Found fossil similarities between current and past species.

Question 6

Darwins theory is based on his…

Answer 6

Trip to the Galapagos Islands

Question 7

What are Darwins 4 observations?

Answer 7

1. Reproduction increases population unless factors limit it.
2. Individuals in a species are not identical.
3. Some variation among individuals is inherited.
4. Not all offspring survive to reproduce.

Question 8

What was Darwin’s major inference from his observations?

Answer 8

Heritable variations among individuals affect probability of surviving & reproducing.

=The probability of passing on those characteristics

Question 9

What was Darwin’s major contribution?

Answer 9

Natural Selection

Question 10

Natural Selection

Answer 10

The differential survival and reproduction of organisms with heritable characteristics.

Question 11

Every species occupies a ___.

Answer 11

“Niche” in their ecosystem

Question 12

Survival of the Fittest

Answer 12

How well a species/member of the species fits into its niche

Question 13

Sexual Selection

Answer 13

The passing down of certain traits that enhance mating success.

Question 14

Convergence

Answer 14

Similar traits/characteristics can develop separately and independently in different species.

Question 15

What is an example of convergence?

Answer 15

1. Bats and birds both fly
2. Dolphins and fish both swim/have fins

Question 16

Homoplasy

Answer 16

Similar features that evolved separately

Question 17

Homoplasy contrasts….

Answer 17

Homology (features based on common ancestry)

Question 18

What is an example of homology?

Answer 18

Seal flippers are similar to a human arm.

Question 19

Analogy

Answer 19

Similar function

Question 20

What is an example of analogy?

Answer 20

An elephant trunk and a human hand.

Question 21

Mendel (heritability)

Answer 21

Created laws of inheritance

Question 22

Hugo de Vries (heritability)

Answer 22

Stated that mutations occur

Question 23

Mutations

Answer 23

Spontaneous changed in an organism’s characteristics

Question 24

Mechanism of Inheritance

Answer 24

Genes are encoded in DNA which are inside all cells.

Question 25

How many chromosome pairs do humans have?

Answer 25

23 pairs (2 copies of each gene)

Question 26

Males have what type of chromosomes?

Answer 26

X and Y

Question 27

What does it mean when genes are "conserved"?

Answer 27

There is little change/difference among species.

Question 28

True or False: There are considerable genetic similarities among all living cellular organisms.

Answer 28

TRUE

Question 29

Linnaeus (1700's)

Answer 29

The classification of animals is based on the similarities among animals.

Question 30

Taxonomy

Answer 30

The classification system of animals.

Question 31

Phylogeny

Answer 31

The evolutionary history of species.

Question 32

Modern classification of species consist of...

Answer 32

Phylogenetic closeness.

Question 33

There is a ___ rate of DNA change.

Answer 33

constant

Question 34

What can changes in DNA be used for?

Answer 34

Estimate when two species diverged from a common ancestor.

Question 35

What are the 6 ways to choose species?

Answer 35

1. Outstanding features 2. Convenience 3. Comparison 4. Preservation 5. Economic Importance 6.Treatment of disease

Question 36

Are most animals invertebrates or vertebrates?

Answer 36

Invertebrates

Question 37

What is the difference between invertebrates and vertebrates?

Answer 37

Invertebrates: Do not have a backbone Vertebrates: Have a backbone

Question 38

Do invertebrates have more or less neurons?

Answer 38

Less neurons but have large complexity in their NS.

Question 39

How do we study evolution in the brain?

Answer 39

Compare the brains of species engaging in different kinds of behaviors.

Question 40

What is an example of studying brain evolution?

Answer 40

Compare the warblers singing to their HVC size (displays song production).

Question 41

HVC

Answer 41

Higher vocal center

Question 42

What is the relationship between brain amount and importance of a function?

Answer 42

The more brain amount, the more important the function is.

Question 43

What are examples of the brain amount and function relationship?

Answer 43

1. Warblers: HVC size and # of songs they know 2. Birds: Hippocampus size and their food storing ability 3. Rats: Cortex devoted to whisker representation and their whiskers.

Question 44

What are the 6 basic similarities across vertebrate systems?

Answer 44

1. Development from a hollow dorsal tube. 2. Bilateral symmetry. 3. Segmentation. 4. Hierarchical control. 5. Separate systems (central & peripheral). 6. Functional specialization

Question 45

What are examples of regions that have been changed/altered?

Answer 45

1. The midbrain optic tectum has becomes the visual reflex center in mammals. 2. All mammals have a neocortex with 6 layers, but now more than 50% of the brain is devoted to the neocortex. 3. Reptiles developed a 3 layered cortex, which may be similar to the mammalian hippocampus (3 layers).

Question 46

Is evolution linearly oriented towards a particular goal?

Answer 46

No (birds and brain size)

Question 47

Brain size must account for ___ size.

Answer 47

Body

Question 48

Smaller animals have a ___ brain-body ration than humans.

Answer 48

Greater

Question 49

Encephalization Factor

Answer 49

Takes into account each class's deviation from the center line.

Question 50

What do brain region proportions in primates display?

Answer 50

The relative importance of the cortex in primates (especially humans). Cortex = higher cognitive functions

Question 51

Regions of the brain that develop later become...

Answer 51

Larger

Question 52

Small changes in genes lead to...

Answer 52

Big changes in the brain EX: Cortex cells are added to outer layers at a later time.

Question 53

What accounts for differences in primate brains?

Answer 53

1. Protracted (later) brain development 2. When genes are turned on/off 3. Whether genes are turned on/off 4. Where genes are turned on/off

Question 54

Where do we see the largest divergence of gene expression?

Answer 54

In humans compared to other primates for brain related genes.

Question 55

Brain Evolution: 4 Million yrs ago

Answer 55

Began walking on two feet

Question 56

Brain Evolution: 2.5 million yrs ago

Answer 56

Stone tools

Question 57

Social Brain Hypothesis

Answer 57

A larger cortex is needed to handle complex social relationships.

Question 58

What are the other suggestions for brain growth (not main)?

Answer 58

1. Behavioral innovations 2. Tool use 3. Social learning (observation) 4. Sexual selection

Question 59

Why is it difficult to get larger brains in humans?

Answer 59

A baby still needs to be able to fit out of the uterus at birth.