Exam 5 Flashcards
Biogeographical evidence of evolution
Different critters in different places
Any evolved trait that helps an organism be more suited to its environment
adaptation
When were dogs domesticated?
14,000 years ago
2 extreme phenotypes become more common (favored over intermediate)
-Selective pressures in different habitats lead to 2 distinct phenotypes
-Diverse Habitats
EX: Snails (brown lives in forest; yellow lives in grassland)
Disruptive Selection
Warbler finch has a beak that
is suited to feeding on insects– small, thin, and pointy
Natural history has been punctuated by catastrophic events that altered the way life developed and rocks were deposited; Repopulation was done by species of surrounding areas
Catastrophism
recessive allele frequency in the H-W theory if equilibrium is:
q
2 components of Biological Species Concept
Prezygotic mating and Postzygotic mating
The frequency of D or d alleles will always be
less than 1
1st to use comparative anatomy to develop classification system for animals
Cuvier
Species occupy different habitats; never meet to mate
Habitat isolation
This improves the fitness of a population
Natural Selection
Structure is evidence of evolution from common ancestor
Ex: Gill pouches in all vertebrates at some point during development OR Whale fins and bat wings that contain same bone structure
Homologous Structures
What is the main selective pressure?
Environment
Black mussels in a pond occupy a rocky shoreline. Mutation in the population introduces a while mussel that occupies sandy shoreline. Over time, white mussel population doesn’t breed with black mussel population and evolves into a new species. This is an example of:
Sympatric Speciation
Origin of a new species
Speciation
True or False: Each finch species has a beak adapted to a particular way of life
True
D alleles divided by # of total alleles:
Frequency
3 forms of Natural Selection
Disruptive, Stabilizing, and Directional
Species are distinguished based on TRAITS
Morphological species concept
True or False: Both wild and domestic wolves continued to interbreed
False
Extreme phenotype is favored (increases in frequency)
-Adapting to a changing environment
EX: antibiotic resistance in bacteria
Directional Selection
True or False: Populations with limited variation are good
False
True or False: All dogs are descended from the gray wolf
True
These are used to study, test, and measure microevolution
-Measure frequency of each allele within a gene pool
Allele frequencies
Anatomical evidence of evolution
Embryological evidence–similar embryo levels on vertebrates
Selecting for a particular phenotype in a mate
Non-Random mating
Different calls of a frog represent which Species Concept?
Morphological Species Concept
When intermediate phenotypes become the most common over time. Ex: Human birth weight
Stabilizing Selection
The frequency of dominant and recessive alleles MUST equal
1
In terms of evolution, fitness means
Reproductive success
Came up with the idea: theres an ideal structure and function for every critter
Linnaeus
Different anatomy of the limbs related evolutionarily
Evolutionary Species Concept
Distinguishing species based on structural traits through the fossil record
Evolutionary Species Concept
In Darwin’s Theory of Natural Selection, Members of a population have
heritable variations
He was the first biologist to propose evolution: more complex organisms are descended from less complex organisms
Larmarck
p is dominant or recessive allele
Dominant
Increased survival and number of offspring is:
Fitness
Lamarcks giraffes did this to evolve:
Stretched their necks to reach upper leaves and the more they personally stretched the longer their necks got individually
A Change of allele frequencies within a population over time is known as
microevolution
Inhibits gene flow between species
Reproductive isolation
Darwins idea of how giraffes got long necks:
Neck length varied, long necks could reach the food and didn’t die out so they continued to reproduce, and before long Natural selection took over and left giraffes with only long necks
Evolutionary changes within a population
- -No new species
- -Genotype and phenotype changes
Microevolution
Incompatible genitalia or floral structures is what kind of isolation
Mechanical Isolation
2 components of Mating in Bio Species Concept
Mechanical Isolation
Gamete Isolation
Species can mate and reproduce viable offspring
Biological species concept
Giraffes once thought to be a single species but different DNA sequences have been found that now separate them:
Phylogenetic Species Concept
Critical traits for distinguishing species
Diagnostic traits
Members of a single species living in the same place at the same time
Population
All the E. Coli in your intestine is an example of a
population
dominant allele frequency in the H-W theory of equilibrium is:
p
Which scientist proposed Catastrophism as a way animals change over time?
Cuvier
Small protein that plays an important role in the electron transport chain within mitochondria of all cells
Cytochrome C
Changes in DNA sequence; extremely rare; sometimes new alleles are made
Genetic mutations
This causes necessary compromises but can’t create a new species
Natural Selection
Study of gene diversity within a population over time (ex: differences in alleles and genotype)
Population genetics
Who had similar ideas to Darwin and published his findings one year later?
Alfred Russell Wallace
All alleles present in a population
Gene Pool
3 components of post-mating:
Zygote mortality
Hybrid Sterility
F2 Fitness
All alleles present within a population
Gene pool
Hybrid zygote not viable and dies
Hybrid Inviability/zygote mortality Mechanism
any evolved trait that helps an organism be suited to its environment
Adaptation
These contain same sets of bones organized in similar ways; modified extensively to meet various adaptive needs
Homologous Structures
Members of a population have heritable variations
More individuals are produced than the environment can support
Individuals vary in their reproductive success
Some individuals have adaptive characteristics
Darwin’s Theory of Natural Selection
Darwin focused on which two species in the Galapogos
Finches and Tortoises
He provided evidence of “descent with modification”; suggested mechanisms -> environmental influences, migration, geographic isolation, and struggle for existence
Count Buffon
DNA base sequence differences:
When similar- suggests recent common descent
When different- suggest more ancient common descent
- Catastrophe affects subset of population
- Allele frequencies change
- –Alleles can be lost
- Strong affect on small populations
- Can lead to bottleneck and founder effects
Genetic drift
True or False: Natural selection has no interference from humans
True
These usually done affect fitness
Mutations
______ is a change in the frequencies of alleles over generations
Evolution
This suggests new species evolve when a population of existing species move into a new habitat or has different diet that interferes with interbreeding
–MOST COMMON WAY A NEW SPECIES IS FORMED
Allopatric Speciation
How many species of Galapogos finches are there?
13
He was aboard the HMS Beagle from 1831-1836
Darwin
Ground dwelling finch has this kind of beak:
Heavy duty; suited to break large seeds
Sperm cant reach/fertilize egg is what kind of isolation?
Gamete Isolation
Prevent mating or limit the success of fertilization
Prezygotic mechanisms
He is the founder of paleontology
Cuvier
Evolution occurs to
Populations
Humans interfere and cause changes in a population is known as
Artificial selection
Darwin also believe that living forms could be descended from:
Extinct forms
Heritable variations are
functional, behavioral, physical and can be helpful or harmful or neutral
According to this person, each species had:
- An ideal structure and function
- A place in the scala naturae (sequential ladder of life)
Linnaeus
Adaptation of a population to its environment; REQUIRES genetic and phenotypic variation in population
- Differences affect reproduction
- Differences must be HERITABLE
Natural Selection
Does diversity exist within a population?
Yes
No physical barrier prevents mating between populations; new species can evolve from population of an existing species if a chromosome MUTATION in one population prevents interbreeding with another
Sympatric Speciation
Which is not a type of microevolution?
- Gene flow
- Genetic drift
- Genetic mutation
- All are examples of microevolution
All are examples of microevolution
Hypothesis that related forms of life evolved in 1 location and then spread to accessible regions
Biogeographical Distributions
To study microevolution, you must
measure allele frequency over time
True or False: Evolution always produces new species
False
Darwin observed that there were similar species in similar habitats leading him to believe
related species modified according to environment
Ex: Tortoises neck and limb length dependent on whether food was on the ground or up higher
Hybrid zygote develops into a sterile adult (think MULES)
Hybrid Sterility
Cactus finch has a beak that is
longer, less curved and split tongue for probing cactus for seeds without getting poked in the eyes
p+q =
1
Courtship patterns are different (different songs, calls, pheromones, etc)
Behavioral isolation
If frequencies are stable:
No microevolution
Give an example of non-random mating
Peacocks are colorful, females then select a particular colorful male due to its fitness
How many alleles of each gene do you have in your skin? (diploid)
2
Can evolution happen on an individual level?
No. Only at a population level
Catastrophe can lead to
Bottleneck effect
- -a narrowing of the population
- next generation has less diversity
Both birds and insects have wings to fly is an example of this structure
Analogous Structures
Name a downside of Founder Effect:
inbreeding
He proposed the Inheritance of Acquired Characteristics
Larmarck; know as Lamarckianism
True or False: Habitat destruction increases genetic diversity
False; no time to evolve
Provided evidence of descent based on Modification
Buffon
Prevents hybrid offspring from developing or breeding
Postzygotic mechanisms
Reproducing at different times of the year is what kind of isolation?
Temporal Isolation
This type of structure is evidence of evolution from a common ancestor as well
ex: Wings of penguins similar to wings of other birds but penguins don’t fly OR human appendix still present even though we don’t need it for a plant based diet
Vestigial Structures
Small subgroup of population starts a new population
Founder Effect
Darwin sailed on what ship?
HMS Beagle
True or False: Genetic Diversity is Good
True
The more amino acids in common between species, the more:
closely related
Darwins theory suggests competition for available resources exists because
there are more individuals produced than the environment can support, the strong survive
These are causes of what?: Genetic Mutation Gene Flow Genetic Drift (inc bottleneck and founder effect) Non-Random Mating Natural Selection
Microevolution
3 components of Premating
Habitat isolation
Temporal (time) isolation
Mechanical Isolation
One genotype or phenotype has advantages which get passed on to offspring
Natural Selection
This person supported a hypothesis of common descent
Darwin
A species is the smallest set of interbreeding organisms that share a common ancestor
-Doesn’t rely on morphological traits
Phylogenic Species Concept
the H-W theory equation:
p2+2pq+q2=1
Name the book Darwin published in 1859
On the Origin of Species
True or False: Domesticated wolves then separated from other wolves
True
Give an example of artificial selection:
Dog breeding; breeder chooses desirable traits and only those dogs breed
All living organisms:
- Use the same basic biochemical molecules
- Utilize the same DNA triplet code
- Utilize the same 20 amino acids in their proteins
Biochemical evidence of evolution
Rare alleles disappear and recessive phenotypes become common
Founder Effect
A common ancestor for 2 different groups of organisms; allows the evolution of organisms to be traced
Transitional fossils
Must do a dance CORRECTLY to mate
Behavioral isolation
q is dominant or recessive allele
recessive
He was the 1st to use comparative anatomy to develop classification system for animals
Cuvier
Proposed Catastrophism
Cuvier
Remains of past life: bones, trails, footprints, droppings
Fossils
Adaptations are products of:
Natural Selection
These don’t affect exons; rarely change the codon meaning the amino acid stays the same
Genetic mutations
Founder of Paleontology
Cuvier
He was a French Naturalist:
Count Buffon
A city is built in a valley between two hillsides. As a result, the populations of either hillside rarely interbreed and over time, enough genetic differences accumulate so a new species is formed. This is an example of:
Allopatric Speciation
He cataloged 44 volumes of all known plants and animals
Count Buffon
Did Darwin travel the Northern or Southern hemisphere?
Southern
4 causes of microevolution
Genetic mutations; Gene flow; genetic drift; natural selection
Study of the range and distribution of critters
Biogeography
Evolution on a large scale
Macroevolution
Alleles from 1 population are moving to another population
- same species
- migration of breeders; pollen
- If constant, populations become very similar
- If rare, populations become different species
Gene Flow
Allele frequencies can be used to determine genotype frequencies when there is
equilibrium
Random chance event changes population
Genetic drift
1st biologist to propose evolution; More complex organisms are descended from less complex organisms
Lamarck
Variations of the same gene are
Alleles
T or F: Diverse environments help maintain genetic diversity
True
