T/F: populations are groups of individuals of the same species living together in different geographic areas
False; populations live in the same geographic areas
T/F: over time, natural selection leads to adaptation as advantageous traits become less common in the population
False; they become more common
T/F: evolution is defined as a change in the allele frequency of a population over time
True
T/F: genetic diversity is reflected by the number of different alleles in a population's gene pool
True
T/F: individuals with different phenotypes will have similar abilities to survive and reproduce in a population
False; different abilities
True or False: Acclimations are learned actions. They are not born with it.
True
mutation...
can be advantageous, neutral, or disadvantageous
genetic drift...
change in the allele frequencies due to random chance
gene flow...
movement of alleles from one population to another
bottleneck effect...
magnification of genetic drift as a result of catastrophes or natural events
founder effect...
occurs when groups leave population and establish new ones
which of the following does not influence allele frequencies in a population
all of the above influences in a population
all of following are true of evolution, except
individuals adapt their genes to improve survival
which is necessary for natural selection to proceed
all of the above
natural selection causes
changes in allele frequencies within a population
all of the following are true of natural selection, except
it works best in genetically uniform populations
which of the following can influence the evolution of a species
all of the above
which of the following best describes evolution
it is the change in heritable traits in living populations over successive generations
The primary pressure on species to change over time is what
natural selection
The development of evolutionary theory is credited to Charles Darwin and _________
Alfred Wallace
which of the following would represent a situation that reduces the effect of genetic drift
the population is very large
allopatric speciation
more likely to have evolved substantial differences leading to speciation; physically separated
sympatric speciation
one species splits into two at a single locality, without the two new species ever having been geographically separated
Sympatric species occur together in an area
-are distinctive entities
-are phenotypically different
-utilize different parts of the habitat
-behave separately
punctuated equilibrium
-long periods of stasis followed by rapid change
-stabilizing and oscillating selection is responsible for stasis
Biogeography
Study of the geographic distribution of species
gradualism
-accumulation of small changes,
-standard view for a long time
ecological isolation
-tiglons do not occur in the wild
-lions and tiger . ranges overlap in india but they use different habitats
mechanical isolation
structure of the male and female copulatory organs may be incompatible
temporal isolation
-2 species of wild lettuce grow along roadsides in the SE U.S.
-Hybrids can be made experimentally and are fertile
-rare in nature because one flowers in early spring and the other in summer
Behavioral isolation
blue-footed boobies select mates after an elaborate courtship display
gametic isolation
egg and sperm from different species may not attract or fuse; prevention of gamete fusion
Natural selection is a process
Only one of several processes that can result in evolution
diversifying selection (disruptive selection)
Natural selection that favors extreme over intermediate phenotypes; eliminates intermediate
directional selection
occurs when natural selection favors one of the extreme variations of a trait; eliminates one extreme
stabilizing selection
Natural selection that favors intermediate variants by acting against extreme phenotypes; eliminates extremes
Fitness
Individuals with one phenotype leave more surviving offspring in the next generation than individuals with an alternative phenotype
Fitness
Ability of an organism to survive and reproduce in its environment
A gene pool is the __________ information in a population.
total genetic
Which of the following are causes of variations?
mutations, environmental factors, genetic recombination, random pairing of gametes
Genetic variation
-Differences in alleles of genes found within individuals in a population
-Raw material for natural selection
Evolution
-How an entity changes through time
-Development of modern concept traced to Darwin
Population genetics
-Study of properties of genes in a population
-Evolution results in a change in the genetic composition of a population
Polymorphic variation
More than one allele at frequencies greater than mutation alone
SNPs
Used to assess patterns in human and natural populations
Selection
Some individuals leave behind more progeny than others, and the rate at which they do so is affected by phenotype and behavior
Frequency-dependent selection
Fitness of a phenotype depends on its frequency within the population
Oscillating selection
Selection favors one phenotype at one time and another phenotype at another time
Artificial Selection
changes initiated by humans
Agricultural selection
Differences have resulted from generations of human selection for desirable traits, such as greater milk production and larger corn ear size
Homologous structures
Structures with different appearances and functions that all derived from the same body part in a common ancestor
Imperfections
some organisms do not appear perfectly adapted
Convergent evolution
Similar forms having evolved in different, isolated areas because of similar selective pressures in similar environments
subspecies
within a single species, individuals in populations that occur in different areas may be distinct from one another
reproductive isolation
do not mate each other or do not produce fertile offspring
Gene exchange
the biological species concept focuses on the ability to exchange genes
prezygotic isolating mechanisms
mechanisms that prevent formation of a zygote
post-zygotic isolating mechanisms
mechanisms that prevent development into an adult
distinctions among species are maintained by
natural selection
stabilizing selection maintains the
species adaptations
hybrids are quickly eliminated from
gene pool
cladogenesis
one ancestral species becomes divided into two descendant species
speciation is a 2-part process
-initially identical populations must diverge
-reproductive isolation must evolve to maintain these differences
2 ways polyploidy occurs
autoploidy and allopolyploidy
adaptive radiations
closely related species that have recently evolved from a common ancestor by adapting to different parts of the environment