BIO101 Final Exam

Theory of Evolution

The scientific concept explaining the process of how species change over time.

Charles Darwin

Known as the father of evolution, he proposed the theory of natural selection and studied finches in the Galapagos Islands.

Natural Selection

The process where organisms better adapted to their environment tend to survive and produce more offspring.

Artificial Selection

The selective breeding of organisms by humans for specific desirable traits.

Hardy-Weinberg Equilibrium

A principle stating that allele and genotype frequencies in a population will remain constant from generation to generation in the absence of other evolutionary influences.

Genetic Drift

Evolutionary changes in allele frequencies due to random sampling error.

Gene Flow

The transfer of alleles or genes from one population to another.

Genetic Drift causes evolution to occur T/F

True

What causes genetic drift

Founder effect

The Founder Effect

when only a few individuals establish a population

The bottleneck effect

when a disaster drastically reduces the size of a population

Hutton

the belief that changes in nature are gradual uniformitarianism

Cuvier

belief that violent events produce changes in nature catastrophism

Lamark

ideas about how species change Hypothesis of Acquired characteristics

Directional

favors one phenotype

disruptive

favors extreme phenotypes

stabilizing

favors intermediate phenotypes

fitness

describes an animals genetic contribution to the next generation

Father of biogeography

Alfred Wallace

Vestigial Structure

homologous to a functional structure in another species

Analogous Structure

externally parts look the same but internally the structure is different

Covergent Evolution

when organisms that are not closely related share similar structures

Embryonic Development

patterns that produce evolutionary clues

Mutations

in homeotic genes produce dramatic body structure changes

What is used to study molecular evolution?

Comparing DNA sequences and proteins

The more amino acid differences between species the more ___________ the common ancestor is

distant

Molecular Clocks

predict the number of mutations in a species

Mutations in a gene occur at a rate of one nucleotide every ten million years. If the gene differs by 4 nucleotides between two related organisms. How long ago did these organisms split from a common ancestor?

20 million years ago

Equilibrium Allele Frequencies do not change t/f

TRUE

Harvey Weinberg equilibrium occurs when the population meets all of the following

• natural selection does not occur

• no mutations

• the population is big enough to eliminate random changes in allele frequencies

• individuals mate at random

• no migration

Why are harmful alleles maintained in a population?

Because of the heterozygote advantage- where a heterozygote is favored over homozygotes

Sexual Selection

results in variation in the ability to obtain mates

Intrasexual selection

occurs when stronger individuals in a population battle to win access to mates

Mutations do not cause evolution to occur T/F

FALSE

Intersexual selection

occurs when members of one sex choose mates with the highest quality features

Can a population bottleneck genetic drift?

YES

Does Gene Flow stop evolution to occur?

NO

Evolution occurs in ________

populations; NOT individuals

What did Lyell believe?

all changes in nature are gradual; renewed uniformitarianism

How old is the earth

4.6 BY

When did the earliest evidence of life appear?

3.6 BYA

Eons

largest unit of time

Palentology

the study of fossils scientists in this field are referred to as paleontologists

Archaeologist

scientists who find fossils

the oldest fossils are how old?

3 BYA

Compression Fossil

a fossil that is in sedimentary rock that has undergone physical compression

Petrification Fossil

an animal dies and is buried, water containing minerals seeds through burial and the minerals replace the organic matter turning the fossil “in to stone”

Impression Fossils

animal dies leaving an impression in the mud and then when this animal decays the mud hardens into rock

Cast Fossil

animal dies in soft sediment and leaves an imprint in the sand. Mud fulls this imprint and turns into rock.

Intact Preservation

where organisms are preserved by being buried in a substance that allows no oxygen to enter. This type minimizes decomposition

Relative Dating

assumes that lower rock layers have older fossils and newer rock layers have newer fossils

Absolute dating dates fossils using ______

chemistry

Radiometric Dating

one way to date a fossil; measures the amount of 14 C in a fossil to calculate how long ago it died

Biogeography

the study of the distribution of species across a planet

what is this structure an example of?

vestigial

microevolution

small evolutionary changes that accumulate in a population these can occur quickly in just a few generations

macroevolution

slow large scale changes

Speciation

the process by which one species splits into two ir more species

habitat isolation

two species live in the same general area but not in the same place

temporal isolation

two species breed at different times

behavioral isolation

there is little or no mate recognition between males and females of different species

gametic isolation

female and male gametes are not compatible

what are the three post zygotic barriers

reduced hybrid viability, reduced hybrid fertility and hybrid breakdown

reduced hybrid viability

most hybrid offspring do not survive

reduced hybrid fertility

hybrid offspring are vigorous but sterile

hybrid breakdown

the first gen are viable and fertile but the offsprings of hybrids are sterile

allospatric speciation

a barrier that separates a population into two groups that cannot interbreed

parapatric speciation

part of a population enters a new habitat bordering the range of the parent species

sympatric speciation

occurs when a new species arises within the same geographic area as a parent species

Adaptive radiation

the evolution of many diverse species from a common ancestor