BIO 110 EVOLUTION EXAM QUESTIONS AND ANSWERS | COMPLETE EVOLUTION
STUDY GUIDE 2026/2027
population - ANS ✔✔group of organisms living in a particular geographic region
evolution - ANS ✔✔a change in allele frequency over time
Jean-Baptiste Lamarck - ANS ✔✔biologist, early 1800s
living species might change over time
Charles Lyell, geologist - ANS ✔✔Geological forces had shaped the earth and were continuing to do so
(1830)
Gradual but constant change
Charles Darwin - ANS ✔✔1809-1882
Darwins round the world theory/voyage
Varied traits exhibited by closely related species
similarities between the fossils of extinct species and the living species in that same area
Thomas Malthus (economist) - ANS ✔✔populations grow much faster than food supplies
Alfred Russell Wallace - ANS ✔✔both Darwin and Wallace are credited for the 1st evolution by natural
selection
Forces of evolution: - ANS ✔✔1. Mutations
2. Genetic drift (founders effect)
3. Gene flow (migration= movement adds alleles to mix/makes a new population)
All are random processes
4. Natural Selection (darwin)
Mutations - ANS ✔✔-the only way in which new variations arise
- every genetic feature in every organism was initially the result of a mutation
- alters DNA sequence
- to be heritable mutations much occur in the sex cells
Genetic Drift - ANS ✔✔- a change in allele frequencies in a population due to random chance.
- does not matter how "fit" an individual is, or how well adapted they are to their environment
EX: natural disease, plane crash
Fixation - ANS ✔✔one alleles frequency reaches 100%
genetic drift reduced the genetic variation in a population
1. the founders effect
, 2. population bottleneck
founders effect - ANS ✔✔subset or original population separates and creates new population with fewer
alleles (more likely in a smaller group)
Population bottleneck - ANS ✔✔the rapid reduction in population size due to famine, disease or
environmental change --> causes change in allele frequency
gene flow - ANS ✔✔migration- the movement of some individuals of a species from one population to
another
- this movement of alleles between populations may change allele frequency
Differential Reproductive Success: - ANS ✔✔different # of surviving offspring= not everyone is
reproducing at the same rate
3 criteria for natural selection to occur - ANS ✔✔1. there must be variation for the particular trait within
a population
2. this variation creates differential reproduction
3. the variation must be inheritable
adaption - ANS ✔✔organisms in a population become better matches to their current environment
through natural selection
directional selection - ANS ✔✔within the range of variation of a trait, individuals at one of the extreme
ends are selected for or against
stabilizing selection - ANS ✔✔individuals with intermediate phenotypes are most fit
disruptive selection - ANS ✔✔individuals with extreme phenotypes experience the highest fitness, those
with intermediate phenotypes have the lowest
(coho salmon/ sneaky copulator)
Honest signal hypothesis - ANS ✔✔signals something about overall heath
(more feathers, antlers, etc shows that you are healthier than another= healthier offspring)
5 Primary lines of evidence of evolution - ANS ✔✔1. fossil record
2. biogeography (life/location)
3. comparative anatomy and embryology
4. molecular biology (genetics)
5. laboratory and field experiments
homologous structure - ANS ✔✔similarities due to common ancestry
analagous structure - ANS ✔✔similarities due to common function
- convergent evolution
altruism - ANS ✔✔the act of performing a costly behavior that benefits someone else
STUDY GUIDE 2026/2027
population - ANS ✔✔group of organisms living in a particular geographic region
evolution - ANS ✔✔a change in allele frequency over time
Jean-Baptiste Lamarck - ANS ✔✔biologist, early 1800s
living species might change over time
Charles Lyell, geologist - ANS ✔✔Geological forces had shaped the earth and were continuing to do so
(1830)
Gradual but constant change
Charles Darwin - ANS ✔✔1809-1882
Darwins round the world theory/voyage
Varied traits exhibited by closely related species
similarities between the fossils of extinct species and the living species in that same area
Thomas Malthus (economist) - ANS ✔✔populations grow much faster than food supplies
Alfred Russell Wallace - ANS ✔✔both Darwin and Wallace are credited for the 1st evolution by natural
selection
Forces of evolution: - ANS ✔✔1. Mutations
2. Genetic drift (founders effect)
3. Gene flow (migration= movement adds alleles to mix/makes a new population)
All are random processes
4. Natural Selection (darwin)
Mutations - ANS ✔✔-the only way in which new variations arise
- every genetic feature in every organism was initially the result of a mutation
- alters DNA sequence
- to be heritable mutations much occur in the sex cells
Genetic Drift - ANS ✔✔- a change in allele frequencies in a population due to random chance.
- does not matter how "fit" an individual is, or how well adapted they are to their environment
EX: natural disease, plane crash
Fixation - ANS ✔✔one alleles frequency reaches 100%
genetic drift reduced the genetic variation in a population
1. the founders effect
, 2. population bottleneck
founders effect - ANS ✔✔subset or original population separates and creates new population with fewer
alleles (more likely in a smaller group)
Population bottleneck - ANS ✔✔the rapid reduction in population size due to famine, disease or
environmental change --> causes change in allele frequency
gene flow - ANS ✔✔migration- the movement of some individuals of a species from one population to
another
- this movement of alleles between populations may change allele frequency
Differential Reproductive Success: - ANS ✔✔different # of surviving offspring= not everyone is
reproducing at the same rate
3 criteria for natural selection to occur - ANS ✔✔1. there must be variation for the particular trait within
a population
2. this variation creates differential reproduction
3. the variation must be inheritable
adaption - ANS ✔✔organisms in a population become better matches to their current environment
through natural selection
directional selection - ANS ✔✔within the range of variation of a trait, individuals at one of the extreme
ends are selected for or against
stabilizing selection - ANS ✔✔individuals with intermediate phenotypes are most fit
disruptive selection - ANS ✔✔individuals with extreme phenotypes experience the highest fitness, those
with intermediate phenotypes have the lowest
(coho salmon/ sneaky copulator)
Honest signal hypothesis - ANS ✔✔signals something about overall heath
(more feathers, antlers, etc shows that you are healthier than another= healthier offspring)
5 Primary lines of evidence of evolution - ANS ✔✔1. fossil record
2. biogeography (life/location)
3. comparative anatomy and embryology
4. molecular biology (genetics)
5. laboratory and field experiments
homologous structure - ANS ✔✔similarities due to common ancestry
analagous structure - ANS ✔✔similarities due to common function
- convergent evolution
altruism - ANS ✔✔the act of performing a costly behavior that benefits someone else
