Anthropology Chapters 1-4

Front 1

What are Darwin's three postulates?

Back 1

1. A population can expand infinitley, but the environment is finite.
2. Natural selection chooses the best adapted animals to survive
3. Variations are transmitted from parents to offspring

Front 2

Convergence

Back 2

Similar traits in unrelated organisms

Front 3

What were the 3 problems with Darwin's theory?

Back 3

1. What maintains variation in a population?
2. Why do offspring seem to share characteristics from both parents?
3. How can natural selection add new traits?

Front 4

What were Mendel's rules?

Back 4

1. Characteristics of organisms are jointly determined by particles inherited from each parent (gene)
2. Different particles from each parent are equally likely to be transmitted to offspring

Front 5

Mitosis

Back 5

A cell divides to create two copies of itself with identical chromosomes

Front 6

Meiosis

Back 6

A cell splits in half creating haploid cells, which contain only one copy of each chromosome

Front 7

Gametes

Back 7

Eggs or sperm

Front 8

Diploid Organism

Back 8

An organism that has homologous chromosomes

Front 9

Haploid Cell

Back 9

The result of meiosis. Contains only one copy of each chromosome

Front 10

Zygote

Back 10

Cell which results from the unity of sperm and egg

Front 11

Recombination

Back 11

When chromosomes get tangled and genes are shuffled around to create more variation

Front 12

Linked Loci

Back 12

When loci for different traits occur on the same chromosome...this means that if genes for hair color and eye color were linked, they would both either be recessive or dominate

Front 13

Correlated Characters

Back 13

One gene affects multiple traits

Front 14

Genetic Drift

Back 14

If a species becomes seperated in two small, isolated areas the gene distrubution will change and new species may evolve

Front 15

Local vs. Global Optima

Back 15

Natural selection selects for adaptations that are best at a specific time and place, not necessarily what is best in the long run

Front 16

Hardy-Weinberg Equilibrium

Back 16

The frequency of genotypes that result from reproduction will remain in equilibrium as long as there are no outside forces affecting them.

Front 17

Fixation

Back 17

Through genetic drift, all individuals in a population should eventually become homozygous for a certain allele at a particular locus...fixation remains until population introduces a new allele

Front 18

Homologous Traits

Back 18

Traits which are due to shared ancestry

Front 19

Analogous Traits

Back 19

Traits which are due to convergent evolution

Front 20

How do scientists detemine whether traits are ancestral?

Back 20

1. Characteristics appear early in development
2. Characteristics appear early in fossil records
3. Characteristics that appear in outgroups

Front 21

Biological Species Concept

Back 21

A species is a group which interbreeds together and are reproductiveley isolated from other groups.

Front 22

Reproductively Isolated

Back 22

Organisms cannot breed with other groups (species) of organisms

Front 23

Ecological Species Concept

Back 23

Natural selection will choose the best adapted organism, regardless of whether or not there is geneflow.

Front 24

Character Displacement

Back 24

If two diverged species are reuinted, the derived differences will cause the two species to compete, thus they would not mate with each other.

Front 25

Reinforcement

Back 25

Natural selection favors physical or behavioral changes which prevents mating between two diverged species.

Front 26

Allopatric Speciation

Back 26

When a species is divided by a barrier, natural selection causes the different populations to adapt to their environments and thus form different species

Front 27

Sympatric Speciation

Back 27

When natural selection favors different adaptations regardless of whether the species is experiencing different environments.

Front 28

Adaptive Radiation

Back 28

When a single species diversifies to fill many niches

Front 29

Which superfamily to humans belong to?

Back 29

Hominoid

Front 30

Phylogeny

Back 30

Classification system which allows us to arrange a group of species that share a common ancestor

Front 31

Why is phylogeny important?

Back 31

1. It is the basis for identification of organisms
2. By comparing a species' ancestors, you can determine why certain adaptations evolved.
3. By realizing which species share common ancestors, we can better compare the features of independent species.

Front 32

Systematics

Back 32

Construction of phylogenies

Front 33

Taxonomy

Back 33

The use of phylogenies in naming and classification

Front 34

Ancestrail Trait

Back 34

A trait which appears early in the evolution of a lineage (was originally there, was not adapted over time)

Front 35

Derived trait

Back 35

Features that have evolved since the time of the last common ancestor of the species(s)

Front 36

Out-groups

Back 36

Taxonomic group that is related to the group in question