STUDY GUIDE

What are "emergent diseases"? How do they come about?

"new" diseases; evolution. this is because as populations of pathogens evolve and genomes of the pathogen changes

3.Most species of butterflies have six walking legs, while some species have four walking legs and two nonwalking legs. If butterflies are compared to other, non-butterfly related insects, we can see that other insects have six walking legs. How does the comparison to the non-butterfly outgroup help to identify derived and ancestral characters? In this example, which trait is derived and which is ancestral?

4 legs - derived 6 legs - ancestral

1.When did early Earth form?

4.6 bil years ago

From the evidences you listed in question #1, which would give scientists the most accurate information?

DNA

How did artificial selection influence Darwin's thinking?

Darwin was worried about other scientists supporting his work so used artificial selection to compare to natural selection; backed up his theory of natural selection

What does the phrase "non-selective pressures" mean?

Events that don't directly affect the phenotypes but lead to a change in population diversity

4. Natural selection only does what is best for the species. Do you agree with this statement? Why or why not?

False; Natural selection has no intentions and it only leads to traits that lead to survival and reproduction. Just because a trait leads to survival does not mean it's good for the species.

1.True or false: natural selection acts on genotypes.

False; it acts on phenotypes

2.True or false: organisms can adapt to their environments if they try to.

False; organisms cannot "try" to adapt because natural selection has no intentions Natural selection acts on traits that lead to survival and reproduction. Natural selection has no knowledge of what organisms need.

How does artificial selection differ from natural selection?

In artificial selection humans select traits that are desirable; domestication of plants and animals. In natural selection "nature" selects traits that are better for survival and reproduction

How is sexual selection similar to directional selection?

In sexual selection males have unique and showy traits which is similar to directional selection where selection is towards 1 phenotype

Why is genetic variation important to survival?

It allows natural selection to increase or decrease frequency of alleles already in the population; enables some individuals to adapt to the environment while maintaining the survival of the population.

What factors contribute to phenotypic variation in a population?

Mutations, genetic drift, migration/gene flow, natural selection

2.Is the Hardy-Weinberg model realistic?

NO its a hypothetical situation that takes place; in real populations allele and genotype frequencies DO change over time

3. Organisms of the same species with different genotypes will always have different phenotypes. Do you agree with this statement? Why or why not?

No; heterozygous

Does the fossil record provide a complete picture of life in the past? Why or why not?

Not a complete picture; more fossils to be discovered

6.Why is evolution a theory?

Not able to be mathematically proven

4. How does the RNA World Hypothesis help to explain a pre-cellular stage of life?

RNA could have been the earliest genetic material

Research an example of natural selection and identify the selective pressure.

Selective pressure - anything that affects survival or reproduction

7. How is our general understanding of the phrase "survival of the fittest" misleading?

This is because the fittest organism simply refers to the organism that can survive and reproduce; not the "fittest"

1.What is the main difference between phylogenetic trees and cladograms?

Trees show the amount of change over time measured by fossils

True or false: mutations can lead to new alleles.

True; it can result in genetic variation

Can an organism's physical environment influence evolutionary change? Why or why not?

Yes, environments can change causing selective pressures to populations

What does it mean if a trait is "highly conserved"?

a trait that has remained relatively unchanged

How do homologous structures differ from analogous structures?

analogous structures are structures that are similar but have separate evolutionary origins; homologous structures are characteristics that are similar in 2 species bc they share a common ancestors

What are some vestigial structures in humans? Describe what they structures/features may have been useful for in the past. You may use the internet to research this.

appendices, tailbones, wisdom teeth

7. Fill in the blank: Nodes represent ___________.

common ancetsors

How is it possible for two species that look similar, to be less related than two species who look completely different?

convergent evolution and analagous structures

2.What is the earliest known fossil?

cyanobacteria

Why might species that live in different geographical areas sometimes resemble each other?

due to convergent evolution; similar envirronments

3. How does ecological stress affect the rate of extinction?

extinction rates quicken

What evidence supports your explanation to problem #1?

fossil record

In what ways is evolution supported (i.e., what are some evidences of evolution?)

fossil record, comparative morphology, biogeography, DNA

How does the idea of descent with modification explain the unity and diversity of life?

heritable traits cchange from generation to generation leading to natural selection and adaptation and thus an increase in genetic diversity

1.Many scientists agree that we are currently in the sixth mass extinction. How does this mass extinction differ from those that occured in the past?

humans are driving it

3. A rare bird, know as Vogelkop Superb Bird-of-Paradise, can be found in Western New Guinea. It has black feathers and a strip of neon teal across its chest. This bird performs a unique courtship dance to attract females. (search for this bird on the internet and you will find footage from National Geographic!) If this bird were tobe placed in an area with a different female species andperform its courtship dance, what would you expect to happen? Why?

it would be unable to mate

4. How can the principle of parsimony be applied to phylogenetics?

least assumptions to create a tree

3. Describe the Miller Urey experiment.

miller and urey found organic compounds and amino acids formed

5.What evidence supports the endosymbiotic theory? Think back to Unit 2.

mitochondria, chloroplasts

1. How does species diversity correlate to the survival of the species

more diversity -> more likely individuals can withstand changes -> survival

5.Why might analyzing DNA sequences be more accurate than analyzing amino acid sequences when creating a phylogenetic tree?

multiple species may require similar proteins but dna sequences are entirely unique

4. How can natural selection promote reproductive isolation in allopatric and sympatric speciation?

new traits in allopatric speciation are more favored in specific geographical locations; in sympatric perhaps a specific niche may be more favorable as a trait

3.What are the five conditions that must be met for a population to be in Hardy-Weinberg equilibrium?

no mutations, random mating, no natural selection, extremely large pop. size, no gene flow

Think back to unit 6, where are genes that code for antibiotic resistance found in bacteria?

plasmids

5.The frequency of individuals who express a recessive disease in a population is 5%. What variable in the Hardy Weinberg equations does the 5% refer to? Why?

q squared

5. Fill in the blank: Evolutionary fitness is measured by ________ success.

reproductive

When comparing DNA sequences of two closely related species what would you expect to find? What about between two distantly related species?

share similarities in amino acids and sequence; vice versa

3. Fill in the blank: If an organism has a more favorable trait, then it will be more likely to _______ and _______.

survive and reproduce

2.In general, how are prezygotic and postzygotic barriers similar? In general, how are they different?

they both are reproductive isolation; one happens before fertilization and the other after

2.If a species goes extinct, it opens up a new niche. How can this potentially lead to speciation of another species?

this new niche may be exploited by a different species

4.What is the purpose of calculating Hardy-Weinberg equilibrium?

to assess whether natural selection or other factors are causing evolution at a particular locus; determines what the genetic makeup of the population would be if it were not evolving

Explain how evolution is an ongoing process in all living organisms.

traits are inherited from generation to generation

1.True or False: a species can diverge while living in the same geographical area.

true; sympatric speciation

Due to the over prescription of antibiotics, many strains of bacteria are developing resistance. Can this resistance evolve (i.e., can the level of resistance change over time)? Provide an explanation for your reasoning.

yes over time the populations of bacteria evolve causing their genome to change