CH 22
1. Historically, who and when did individuals contribute to ideas about what we know
as “evolution” today.
- new era of biology began in 1859 when Charles Darwin published “The Origin of Species”
that noted the diversity of systems as each species are descendants of ancestral species
a. Lamarck vs. Darwin? How did their views of “evolution” differ?
Darwin: natural selection and survival of the fittest occurred
Lamarck: species went through changes in response to their environment
b. Who contributed ideas about how living organisms came to exist on Earth before
Darwin?
- The Greek philosopher Aristotle viewed species as “fixed” and arranged them on a scale
called “scala naturae”
-The Old Testament says that species are designed by God and are therefore “perfect”
- Carolus Linnaeus thought that the creator made each animal for a specific purpose.
Made taxonony, which it the classification of organisms.
2. What exactly specifically were Darwin’s contributions to the area of “evolution”
a. What were his research areas?
- Darwin originally went to South America
- He then went to the Galapagos Islands where he connected similarities between the
South American species to the species on Galapagos
b. How did his ideas differ from others?
- His ideas were different from others as he believed in “descent with modification” and
natural selection, meaning those with more favorable inheritable traits were more likely to
survive and reproduce
c. What were his 3 broad observations and how do they tie to evolution?
1.unity of life (means all organisms are related in a way as they are descendants from an a
common ancestor)
2.diversity of life (history of evolutionary life is like a tree with branches)
,3. ways organisms are suited to life and their environment
d. How do Artificial Selection, Natural Selection, and Adaptation differ?
Artificial selection: modifying species by selecting and breeding with individuals with
desired traits
Natural Selection: individuals with more favorable inherited traits are more likely to survive
and reproduce
Adaptation: adapting to have better traits suited for the environment
3. What are the key features of Natural Selection?
- heritable traits survive and reproduce at a higher rate
- raises the frequency of adaptations that are favorable in each environment
- if the environment changes, adaptation may occur that gives rise to a new species
- populations evolve over time (NOT INDIVIDUALS)
- increases or decreases heritable traits that vary in a population
- adaptation varies with different environments
4. What are the differences between Darwin’s OBSERVATIONS and INFERENCES and what
were they?
Observation 1 – members of a population often vary in their inherited traits
- They come with different traits to allow for different variations that could/couldn’t
be suited for the environment
Observation 2 – all species produce more offspring than the environment can support,
leaving many offspring to fail to survive and reproduce
- Allows for enough to still be alive to reproduce the next generation
Inference 1 – individuals who’s inherited traits have a higher probability of surviving and
reproducing leave more offspring than others
- Since their traits are more desirable for the environment, there are more alive than
those not desirable to pass on traits
Inference 2 – Unequal abilities of individuals to survive and reproduce leads to
accumulation of favorable traits in the populations over generations
, - over each generation only the fittest of their generation survive to pass on their traits,
making every next generation more fit
5. What is the world population now? Has it grown or shrunk in recent decades?
- The world population now is 8.202 billion. It is growing as humans have no biological
predators and enough medical technology to keep most sicknesses at bay. This may
change if the amount of food resources in the future is not enough
6. What are the four types of data document the pattern of evolution and examples of
each one?
1. direct observations (ie. Noticing that different birds have different sizes or lengths
depending on where they live and what they eat)
2. homology (ie. Humans, cats, whales, bats share the same bones in their
arm/flipper/wings)
3. the fossil record (ie. Fossils found in the top layers of rock have similar structures to
current organisms, meaning the fossil can be their ancestor, spinal bones of animals)
4. biogeography (ie. They originate in close proximities)
7. What is the difference between Anatomical and Molecular Homologies and how can
they be used in studying evolution?
Molecular level: genes shared amongst organisms inherited from common ancestors (ie.
Pseudogenes AKA genes that code for nothing)
Anatomical level: physical features shared amongst ancestors
a. What are vestigial structures?
- remnants of features that served a function in the organism’s ancestors
b. Examples of vestigial structures in organisms?
- minor end of tail on the vertebrae of humans, remnant of animals (coccygeal tail
vertebrae)
- third molar (called wisdom teeth in humans)
-small vermiform appendix at the end of the human intestine
1. Historically, who and when did individuals contribute to ideas about what we know
as “evolution” today.
- new era of biology began in 1859 when Charles Darwin published “The Origin of Species”
that noted the diversity of systems as each species are descendants of ancestral species
a. Lamarck vs. Darwin? How did their views of “evolution” differ?
Darwin: natural selection and survival of the fittest occurred
Lamarck: species went through changes in response to their environment
b. Who contributed ideas about how living organisms came to exist on Earth before
Darwin?
- The Greek philosopher Aristotle viewed species as “fixed” and arranged them on a scale
called “scala naturae”
-The Old Testament says that species are designed by God and are therefore “perfect”
- Carolus Linnaeus thought that the creator made each animal for a specific purpose.
Made taxonony, which it the classification of organisms.
2. What exactly specifically were Darwin’s contributions to the area of “evolution”
a. What were his research areas?
- Darwin originally went to South America
- He then went to the Galapagos Islands where he connected similarities between the
South American species to the species on Galapagos
b. How did his ideas differ from others?
- His ideas were different from others as he believed in “descent with modification” and
natural selection, meaning those with more favorable inheritable traits were more likely to
survive and reproduce
c. What were his 3 broad observations and how do they tie to evolution?
1.unity of life (means all organisms are related in a way as they are descendants from an a
common ancestor)
2.diversity of life (history of evolutionary life is like a tree with branches)
,3. ways organisms are suited to life and their environment
d. How do Artificial Selection, Natural Selection, and Adaptation differ?
Artificial selection: modifying species by selecting and breeding with individuals with
desired traits
Natural Selection: individuals with more favorable inherited traits are more likely to survive
and reproduce
Adaptation: adapting to have better traits suited for the environment
3. What are the key features of Natural Selection?
- heritable traits survive and reproduce at a higher rate
- raises the frequency of adaptations that are favorable in each environment
- if the environment changes, adaptation may occur that gives rise to a new species
- populations evolve over time (NOT INDIVIDUALS)
- increases or decreases heritable traits that vary in a population
- adaptation varies with different environments
4. What are the differences between Darwin’s OBSERVATIONS and INFERENCES and what
were they?
Observation 1 – members of a population often vary in their inherited traits
- They come with different traits to allow for different variations that could/couldn’t
be suited for the environment
Observation 2 – all species produce more offspring than the environment can support,
leaving many offspring to fail to survive and reproduce
- Allows for enough to still be alive to reproduce the next generation
Inference 1 – individuals who’s inherited traits have a higher probability of surviving and
reproducing leave more offspring than others
- Since their traits are more desirable for the environment, there are more alive than
those not desirable to pass on traits
Inference 2 – Unequal abilities of individuals to survive and reproduce leads to
accumulation of favorable traits in the populations over generations
, - over each generation only the fittest of their generation survive to pass on their traits,
making every next generation more fit
5. What is the world population now? Has it grown or shrunk in recent decades?
- The world population now is 8.202 billion. It is growing as humans have no biological
predators and enough medical technology to keep most sicknesses at bay. This may
change if the amount of food resources in the future is not enough
6. What are the four types of data document the pattern of evolution and examples of
each one?
1. direct observations (ie. Noticing that different birds have different sizes or lengths
depending on where they live and what they eat)
2. homology (ie. Humans, cats, whales, bats share the same bones in their
arm/flipper/wings)
3. the fossil record (ie. Fossils found in the top layers of rock have similar structures to
current organisms, meaning the fossil can be their ancestor, spinal bones of animals)
4. biogeography (ie. They originate in close proximities)
7. What is the difference between Anatomical and Molecular Homologies and how can
they be used in studying evolution?
Molecular level: genes shared amongst organisms inherited from common ancestors (ie.
Pseudogenes AKA genes that code for nothing)
Anatomical level: physical features shared amongst ancestors
a. What are vestigial structures?
- remnants of features that served a function in the organism’s ancestors
b. Examples of vestigial structures in organisms?
- minor end of tail on the vertebrae of humans, remnant of animals (coccygeal tail
vertebrae)
- third molar (called wisdom teeth in humans)
-small vermiform appendix at the end of the human intestine
