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100 Cards in this Set

  • Front
  • Back
The process by which organisms change over successive generations
Why do scientists consider evolution to be the unifying concept of biology?
Almost everything we study in this course is either a evolutionary mechanism or a product of evolution
What were the initial explanations of the origin of species which involved special creation?
1)organisms divinely created and UNCHANGED
2)No modification or extinction
Who was Jean-Baptise Lamark?
Man who believed that animals changed by evolution through inheritance of ACQUIRED traits/characteristics
What did Charles Darwin and Alfred Russel Wallace believe in?
They believed that species changed by evolution through NATURAL SELECTION
Why isn't Lamarks idea of inheritance of aquired traits taught anymore?
Because it is wrong, it bases its idea on the fact that an animal can aquire a trait during its lifetime and pass it on to its lifespring. For instance if you lifted weights you would pass that muscle onto your children. FALSE!
Why was Lamarck's ideas, although wrong, important?
Because he was the first to suggest organisms could change. He just suggested the wrong mechanism. Your genes do not change like he was suggesting
What does natural selection describe?
how populations evolve as favorable variations are disproportionately preserved through successive generations.
Who thought of the idea of natural selection?
D)both Wallace and Darwin independently and simultaneously
D)both Wallace adn Darwin!
What is this an example of?
Faster rabbits survive longer and pass their traits onto their children
Natural selection
Where was Darwin born?
England in the 1800s
What did Darwin study?
Medicine and theology
What did Darwin eventually become?
A naturalist
What voyage did Darwin go on and why was it important?
5 year voyage on the HMS Beagle that allowed him to map coastlines and visit many places including South America and the Galapagos Islands where he saw the changes in finches; inspired his thoughts about evolution
What other scientific ideas did Darwin use in forming his theory of evolution?
Fossil Record
Lamarckian ideas
Artificial Selection
Who figured out an important thing about geography and what was it?
Charles Lyell and that geologic processes were slow and continuous
Who noticed the importance of the fossil record and what was it?
Georges Cuvier and he noticed there was evidence of extinction
What did Lamarck notice?
That organisms changed over time
What is the importance of artificial selection to Darwin?
The creation of domestic animal breeds. All the same speices, but incredibly different
What is evidence for Evolution?
A)fossil record
B)radiometric dating
C)Comparative morphology and embyology
D)molecular biology
E)experimental evidence
F)all of the above
F)all of the above!
What is the fossil record?
Record of ancient life providing relative age
What are some factors of the fossil record?
-Oldest layers contain more primitive and extinct forms of life
-Newer strata contain modern organisms
-Transitional forms can be seen
What is Radio metric dating?
Method of aging rocks and organic material
because radioactive elements gradually degrade into more stable non-radioactive elements at very specific rates (half lives)
What is the half life of C14 to C12?
5730 years
What is the half life of K40 to Ar40?
A)5730 years
B)12 million years
C)4.5 billion years
D)1.25 billion years
1.25 billion years
What is the half life of U238 to Pb206?
A)166 Billion years
B)45 million years
C)4.5 billion years
D)1.25 billion years
4.5 billion years
What processes can effect radiometric dating?
none, it is very consistent, weather temperature climate etc do not effect
Why is Carbon 14 dating used most of all other types of other radiometric dating techniques?
Carbon 14 is used because everything has carbon in it that lived and you lose carbon at a specific rate. good for things that are a few thousand years old, but not incredibly old
What is comparitive morphology?
looking at the shape and anatomy of animals because they reflect ancestry and adaptation
What is a homologous structure?
structural similarity in descendants from a common ancestor
example is bird wings and bat wings. they have the same bones and evolved similar ancestors
What is an example of a homologous structure?
A)pelvis bones in snakes
B)slim body in dolphins and seals
C)same bones in whales, cats and bats in areas
C)same bones; shows common ancestry
What is an analogous structure?
Structurally dissimilar features that preform the same function. Animals evolved same structures for same reason, but not because of similar ancestry. Wings in birds and wings in insects
What is an example of an analogous structure?
A)Same bones in human hands and whale fins
B)slim bodies in dolphins and seals
C)pelvis bone in whales
B)slim bodies in dolphins and seals
What is a vestigial structure?
Non functioning remnants of a structure that was functional in an ancestor
What is an example of a vestigal structure?
A)Small pelvis and legs in whales
B)Same bones in hands of bats and whales
C)bats in birds and bats
A)small pelvis and legs in whales
What does comparitive embryology reflect?
Common ancestry is reflected in embryonic development-traits of earliest ancestory retained in descendants
What is a good example of comparitive embryology?
Looking at vertebrate embryos. When looking at them all you can see we all have tails and gill slits and nerve cords. This shows a common ancestry. We all derive from teh earliest vertebrate FISH!
How is molecular evidence used to determine the degree of relatedness of organisms?
The similarity in DNA structure indicates degree of relatedness and using Cytochrome C gene which every ogranism has they can find out whats more related
What gene is used a lot to find molecular evidence?
The Cytochrome C gene
How do each of the evolutionary evidences work together?
each one validates the others
Chapter 17 How do populations evolve?
Populations evolve through the accumulation of small genetic changes. Various processes cause changes in the abundance of different genotypes
What is a population?
A group of individuals of the same species within the same geographic area
What is a gene pool?
The sum of a population's genotypes
What do microevolutionary processes do?
They are phenomena that modify gene pool
What are the five microevolutionary processes?
Gene flow
Gene drift
non-random mating
natural selection
What is a mutation?
A change in an individuals DNA
What is gene flow?
movement of individuals among gene pools
What is genetic drift?
Random changes in the number of individuals with different traits
What is natural selection?
Different survival and reproduction of individuals due to their traits

The preservation of beneficial allels in a gene pool due to improved survival or reproduction of the individuals possessing them
What do mutations generally do to the body?
Generally they are harmful or nuetral. sometimes they are beneficial though
What is the only way to create new alleles in a gene pool?
Mutation. It increases variation
Are the rates of mutation generally high are low in most organisms?
Generally low rates of mutations in organisms
What makes populations more similar?
The sharing of alleles in gene flow (when individuals from one population migrate to another)
What kind of populations does genetic drift generally effect most?
Small populations because they are more likely to lose rare alleles when there are fewer people who carry it
What are the bottleneck and founders effects?
They are types of genetic drift
What is the Bottleneck effect of genetic drift?
Change in alleles due to reduction of population size (disease, catastrophic event etc)
What is the Founders effect?
Occurs when a few individuals start a new population.
What do population bottlenecks tend to do?
Reduce gene pools
What is nonrandom mating?
Changes in gene pool resulting from unequal mating frequency
Who does nonrandom mating generally effect?
what is the preservation of beneficial alleles in a gene pool due to improved individuals possessing them?
Natural selection
Three things that make natural selection possible
The fact that populations are genetically variable
-the fact that traits cause variation are heritable
-individuals with traits that enhance survival and/or reproduction leave the most offspring therefor favorable traits are passed and increase more than unfavorable ones
When talking about natural selection, how do gene pools change over time?
gene pools change as favorable traits increase relative to the unfavorable ones since individuals with the favorable traits survive better and produce more offspring
What are the three types of natural selection?
Stabilizing selection
Directional Selection
Disruptional Selection
What is stabilizing selection?
A type of natural selection where a range of phenotypes becomes very narrow (stabilized around an optimal value)
What is directional selection?
A type of natural selection where a shift in range of phenotypes in one direction
What is disruptional selection?
A type of natural selection where there is a selection for extreme phenotypes
What has human birth size been affected by?
Stabilizing selection-range of phenotypes becomes very narrow (stabilized around an optimal value)
Where does disruptive selection result from?
selection for extremes in a gene pool results in disruptive selection
What are some examples of natural selection?
Antibiotic resistance in bacteria-bacteria that are weak die and those that arent survive and reproduce making population resistant to antibiotic
Pesticide resistance in insects-same concept big populations of bugs means huge genetic diversity, kills most but some survive that are resistant and reproduce
peppered moth-when lichens were on trees the peppered were favored and became a bigger population but when industrialization caused lichens to fall off dark moths were favored more ENVIRONMENTAL CHANGE DROVE NATURAL SELECTION
What is the peppered moth example a example of?
Natural selection
and caused by enviromental change
A group has to be what in order to survive changes?
genetically diverse
Chapter 18 What is macroevolution?
The evolution of new kinds of organisms (species) through evolutionary processes
What is the Biological Species Concept?
A group of actually or potentially interbreeding natural populations which are reproductively isolated from other such groups (groups that interbreed or can interbreed) species have to be able to breed and reproduce
What is speciation?
The derivation of new species
How does speciation result?
from independent microevolutionary changes in different populations of the same species
In order for speciation what must happen?
Populations must be isolated with separate gene pools
genetic divergence-changes in gene pools resulting from influence of microevolutionary changes in isolated populations
What are the two types of speciation?
Allopatric and Sympatric
What is Allopatric Speciation?
Geographically isolated populations diverge. seperated populations that diverge from each other
What is Sympatric Speciation?
Divergence of populations in the same geographic area
-could be from ecological separation due to difference in timing of reproduction, behavior or resource specialization, different habitat likes
-genetic accidents/hybirdization
Squirrels on separate sides of the Grand Canyon that have adapted differently and can no longer reproduce is an example of what type of speciation?
Allopatric speciation
What are genetic accidents (forms of sympatric speciation) most common in?
What is this an example of?
A bug population that when a nonnative plant is introduced, some eat it and their tounge length slowly adapts over generations to be smaller?
sympatric speciation
How can speciation occur rapidly?
through genetic accidents- polyploidy in wheat creates sterile hybrid that can not reproduce with its parent generations, only itself
What is a reproductive isolating mechanisms?
factors that prevent different species from interbreeding
What are the types of reproductive isolating mechanisms?
Ecological isolation
Temporal isolation
Behavioral isolation
Mechanical isolation
Gamete isolation
Hybrid inviability
what is ecological isolation?
species occupy different habitats
what is temporal isolation?
species have different activity or reproductive cycles
What is behavioral isolation?
incompatible mating behavior (..its like foreplay if it doesnt work then they wont mate)
What is mechanical isolation?
anatomical barriers..such as a great dane and a poodle..the parts dont work
What is hybrid inviability?
Hybrid offspring are sterile like a horse and donkey making a sterile mule
What do species that are prone to speciation likely to exhibit?
Adaptive Radiation
What is adaptive radiation?
The derivation of many diversely adapted species from a single ancestor
What are the finches on the galopogos islands an example of?
Adaptive Radiation
What is taxonomy?
a naming and classification that organizes into categories based on similarities and each species has a unique binomial name composed of 2 Latin words
Who is Linnaeus?
Man who in the 1700s who created the taxonomy system
What was the problem with Linnaeus system of taxonomy?
It preceded Darwin so it had no evolutionary component.
Why do we use the Latin binomial name instead of just what we know?
It is more specific. We call a certain frog a Green Frog, but there are Green Frogs in other countries and so by looking at the binomial name we see specifially what it is
What is cladistics?
Deriving evolutionary relationships by reconstructing ancestry based on primitive and derived features. Made in the 1960s
Why is cladistics better than taxonomy?
Cladistics shows how and where everything comes from and how close their ancestors are related