Chapter 18 Pt 1
What is the correct way to write a scientific name?
Genus species
How does the Biological Species Concept define a species vs the Morphological Species Concept?
Biological Species Concept defines a species based on whether there is gene flow between the two species. The two species remain separate due to biological reproductive barriers. Morphological Species Concept defines a species based on significant morphological and anatomical differences.
Fill in the blanks: Evolution acts on the ______________, whereas natural selection acts on the ____________.
Population, individuals.
What is a polytomy vs a sister taxa in a phylogenetic tree?
Sister taxa are two branches from the same node, polytomy is 2+ unresolved lineages from the same node.
What are homologous vs analogous structures?
Homologous structures have the same common ancestor. Analogous structures have different common ancestors.
What were the two concepts introduced by Darwin on the “Origin of Species?”
Natural selection and descent with modification.
What is the difference between allopatric and sympatric speciation?
Geography. Allopatric speciation occurs with geographic isolation, sympatric occurs within the same environment
What are the three ways in which sexual reproduction can result in heritable variation?
Crossing over, independent assortment, and random fertilization.
What two elements must a clade have? What is another word for a clade?
Common ancestor and all of its descendents. Clade = monophyletic group
What does it mean if an allele is “fixed”?
It means there are no other gene variants available in the population.
MRSA antibiotic resistance is an example of what process? How did it occur?
Natural selection. Antibiotics wiped out the individuals without the antibiotic resistance gene. Those with the antibiotic resistance gene survived, allowing the allele frequency of the antibiotic resistance gene to increase.
What happens with the reproductive barriers when stability occurs in the hybrid zone? What happens with the hybrids? Parents?
Reproductive barriers remain the same, hybridization continues. Parent species continues.
What happens to allele frequencies and diversity in a population after genetic drift?
What element do paraphyletic groups lack in a phylogenetic tree? Polyphyletic groups? (Rephrased, why can they not be considered a clade?)
Paraphyletic groups lack all of the descendents, but show a common ancestor. Polyphyletic groups show distantly related ssp but not their common ancestor
What are the 5 pieces of evidence of evolution?
What are the 5 misconceptions of evolution?
In a dense forest, there are two populations of frogs: one population that lives near the riverbanks and another that resides deeper in the forest. Both populations are of the same species, but they have different mating calls. The riverbank frogs have a higher-pitched call, while the forest frogs have a lower-pitched call.
Behavioral isolation
In a population of birds, the size of the eggs they lay varies. Birds that lay very small eggs tend to have higher mortality rates for their chicks, while birds that lay very large eggs struggle to provide enough resources for all their offspring. Over time, most birds in the population lay eggs of medium size. What type of natural selection is occurring? What is happening to genetic variation?
Stabilizing. There is less genetic variation.
What is the principle of maximum parsimony? How is it determined?
The method of choosing the “best” phylogenetic tree, meaning it has the least evolutionary events and the events occurred in the simplest (and most obvious) way.
How did gradualism and uniformitarianism help shape Darwin’s idea of evolution?
Evolution is a slow, continuous process (gradualism) that has occurred over millions of years (uniformitarianism stated that the Earth is extremely old)
What is Wallace’s Line and how does it contribute to evidence of evolution?
Wallace’s Line is a hypothetical line that shows the ocean channel separating Asian and Australian islands that prevents gene flow between the islands. It is a great example of biogeography, which proves evolution.
What is the resulting ploidy of an aneuploidy gamete? What is it after mating with a normal gamete?
Aneuploidy gamete: n-1 , n+1, n. After fertilization: 2n, 2n+1, 2n-1
In many species of birds, males display vibrant plumage and perform intricate courtship dances to attract females. Females tend to choose mates based on these traits, preferring males with more colorful feathers and more elaborate displays. This is an example of what kind of sexual selection?
Intersexual selection
What are the differences in cell walls between Eukarya, Archaea, and Bacteria?
How many species are involved in autopolyploidy? Allopolyploidy?
Allopolyploidy = 2 ; Autopolyploidy = 1