Download Evolution II Task Review Answers

Evolution II Task Review Answers
Task 1
1. Define Co-evolution and provide an example

When two species each evolve in response to each other over a long period of time

Ex. Humming birds and the plants they drink nectar from
2. What type of natural selection will most likely result in speciation?

Disruptive Selection
3. Homologous structures are associated with what type of evolution?

Divergent Evolution
4. Which rate of speciation is the picture depicting?

Gradualism
Task 2
•
Name and describe the three types of natural selection.
1. Directional- Individuals with a more extreme form of trait have higher fitness
2. Stabilizing- Having average form of trait has highest fitness
3. Disruptive-Individuals with any extreme trait has a higher fitness
Disruptive Selection
Task 3
1. Humans, chimpanzees, whales, and bats all have the same bones in their arms, fins, or wings:
Homologous structures
2. The human gene for your muscle protein is different from monkey muscle protein in 4 places
and different from a chicken’s gene in 25 places: Biological molecules
3. A deep sea fish has remnants of an eye but is blind: Vestigial structures
4. Honey possums lick nectar from flowers using a long tongue made of soft muscle. Butterflies lick
nectar from flowers using a long tongue made of hard protein: Analogous structures
5. 600 different species of cichlid fishes have diversified in Eastern Lakes in Africa. Fish lineages
evolved to take advantage of different foods (including insects, algae, mollusks, small fish, large
fish, even fish scales): Biogeography
6. The beak of a bird and the beak of a giant squid are developmentally different, but serve the
same function: Analogous structures
Task 4

Name and describe the 5 factors that push a population out of equilibrium
1. Genetic Drift: The amount of an allele changes due to random events, mostly affects small
populations, lose alleles if not enough in population to mate or if catastrophe occurs
2. Gene flow/migration: movement of individuals in or out of a population
3. Mutation: Produces and introduces new alleles in a population, new allele can create beneficial
trait
4. Non-random mating: Can increase certain traits and reduce others through sexual selection
5. Natural selection: Organisms best suited to their environment live to reproduce and pass on
their genes, acts on a phenotype
Task 5

Double Bubble for Gene Flow and Genetic Drift
Similarity: both disrupt genetic equilibrium, both cause a change in allele frequencies
Differences: Gene Flow: due to a chance event, generally occurs in small populations, lose alleles
Genetic Drift: due to migration, can occur in any size of population, can gain and/or lose alleles

Double Bubble for Sympatric and Allopatric Speciation
Similarity: ways to create new species, are barrier is present between the populations
Differences: Sympatric: due to geographic boundaries, species don’t come into contact with one another
Allopatric: due to reproductive boundaries, species come into contact with one another
Task 6
1. Adaptive radiation: a type of divergent evolution that occurs very quickly in a given area, the
ancestral finches came from South America and spread to the different islands and adapted to
their new environments
2. Double bubble gradualism and punctuated equilibrium
Similarity: used to describe the rate that speciation occurs
Differences: gradualism: slow divergence,
Punctuated equilibrium: periods of equilibrium (no change), then
Task 7
1.
2.
3.
4.
Variation: differences in alleles/traits in a population
Three causes: mutation, recombination, random pairing of gametes
When graphed shows a bell curve or normal distribution shape
If there was no variation, the species might not be able to adapt to changes in the environment
and die out
Task 8
Vocabulary word being depicted:
1. A population of rabbits suffers a loss of 90% of their population due to a tornado: genetic drift
2. The female mallard will only mate with the male mallard that displays the most green: nonrandom mating
3. A leopard frog mates with a brown frog but the eggs do not develop into an adult: Post-zygotic
sympatric speciation
4. A river forms separating a population of frogs resulting in speciation: allopatric species
5. The human appendix: vestigial structure
Task 9

Name and describe the 7 lines of Evidence of Evolution
1. Paleontology: Fossils provide geologic evidence of evolution, shows that life has not
always been the same
2. Vestigial structures: Remnants of organs or structures that had a function in an early
ancestor, shows that these organisms are descendants from organisms that used
them
3. Homologous structures: Body parts that are similar in structure, but may have
different functions, that in the past they did the same job and came from a common
ancestor
4. Analogous structures: Body parts that are similar in structure, but may have
different functions, indicates that in the past they did the same job and came from a
common ancestor
5. Biogeography: Geographical distribution of living things, similar species are found in
similar places showing common ancestry
6. Embryology: Some stages of embryo development of different organisms are
similar, shows common ancestry
7. Biological Molecules: Living things have similar proteins, which means they have
similar DNA, the more closely related the molecules are means they share a more
recent common ancestor