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Which scientist formulated the theory of evolution through natural selection?
Charles Darwin
Lamarch's ideas about evolution were wrong because he proposed that___?
acquired characteristics can be inherited
Lyell's "Principles of Geology" influnced Darwin because it explained how___?
The surface of the Earth changes over time
A farmer's use of the best livestockn for breeding is an example of___?
artificial selection
The ability of an organism to survive and reproduce in its natural environment is called___?
What is an important concept in Darwin's theory of evolution by natural selection
descent with modification
What does not provide evidence of evolution?
natural variation within a species
Why do DNA and RNA provide evidence of evolution?
In most organisms, the same codons specify the same amino acids
A bird's wings are homologous to ___?
A dog's front legs
Study of biogeography helps scientists___?
make connections between where modern species and their ancestors lived
In vertebrates, groups of embryonic cells developing in the same order and in similar patterns result in ___?
homologous tissues and organs
The wing of a bird and the wing of an ancestor have similar functions, but they evolved independently. This is an example of___?
analogous structures
The DNA in yeast, grizzlt bears, centipedes, and palm trees all share
the same genetic code
Within a species, great heritable variation___?
increases the likelihood of a species' adapting to and surviving environmental changes
camouflage and mimicry are example of___?
natural selection acts only on___?
inherited traits
Darwin's theory of descent with modification refers to ___?
the process of species evolving from common ancestors
Dawrin realized that Malthus' ideas about human population growth applied even more to other organisms, such as why ___?
oysters produce millions of eggs but only a few survive
Hutton and Lyell's research suggested that Earth ___?
changes slowly over long periods of time
How did Darwin explain his observation of fossils of marine animals found several thousand feet above sea level?
geological events caused the ancient seafloor to move to a higher elevation
Lamarck proposed that species changed due to___?
use or disuse of organs
Selective breeding of domesticated organisms by humans to enhance useful traits is known as ___?
artificial selection
Darwin observed that different habitats within a local area contained animal species that were ___?
different yet cloesly related
the process of change over time
What was the name of the voyage Darwin went on?
HMS Beagle
On his voyage, Darwin noticed that similar habitats in different parts of the world contained
different but ecologically similar plants and animals
Darwin drew support for his theory of evolution from the observation that fossils ____?
of some extinct animals are similar to living species
When and where was Darwin born?
February 12, 1809 in England
In what year did Darwin begin his voyage? How long was it? Where was it?
1831; 5 years; along the coastline of South Africa
What 3 distincitve patterns of biological diversity did Darwin notice as he travelled?
1. species vary globally
2. species vary locally
3. species vary over time
remains or traces of ancient organisms
Natural selection occurs in any situation in which:
1. more individuals are born than can survive
2. there is natural heritable variation
3. there is a variable fitness among individuals
natural selection is the ___ force of evolution
What were Hutton's and Lyell's ideas about the age of Earth and the processes that shape the planet?
Earth is extremely old and the processes that changed Earth in the past are the same processes that operate in the present.
What is an acquired characteristic? What role did Lamarck think acquired characteristics played in evolution?
Traits altered by an individual organism during its life are called acquired characteristics. Organisms could use or not use organisms/resources to acquire or not acquire certain characteristics.
What parts of Lamarck's hypotheses have been proved wrong? What did Lamarck get right?
wrong= organisms don't have an inborn drive to become perfect; evolution does not mean that a species becomes "better" or "worse". right=species are not fixed
What three kinds of variations among organisms did Darwin observe during the voyage of the Beagle?
Rheas, Galapagos Islands, and fossils
Who wrote "The Orgins of Species?"
The preserved remains of organsims that loved long ago, often found in rocks and typically resemble parts of living organisms
through ____ evolution, unrelated species in similar environments evolve similar body functions from dissimilar underlying structures called ___
analogous structures
through ___ evolution, cloesly related species living in dissimlar environments evolve dissimlar body functions from similar underlying structures called ___
homologous structures
some species of organisms have _____ with no apparent purpose, which are homologous to functional structures in other species
vestigial structures
the wing of a butterfly and the wing of a bird are ___ structures
the forelimb of a human and the forelimb of a whale are ___ structures
artificial selection
organisms may be modified by controlled selection
Before Darwin, most people thought that species were ____?
incapable of change
Who proposed that an internal drive toward complexity within cells is the driving force of evolution?
In ____ evolution, the two forms being modified are ____
convergent; unrelated
convergent evolution resluts in
analogous structures
What proposes that living organisms inherited body parts modified through use or disuse
inheritence of acquired characteristics
What is homologous to the human arm?
tail of a salamander
Evidence for evolution
1. biochem
2. embryos
3. comparative anatomy
4. domestication of plants and animals
Fossils provide direct evidence for ___?
structural similarities and differences
gene flow
the movement of alleles from one population to another owing to the migration of individual organisms
genetic drift
change in allele frequencies of a small population purely by chance
natural selection is primarily an issue of ____
differential reproduction: organisms with favorable alleles leave more offspring that do other individuals with less favorable alleles
natural selection acts on the ___
_____ selection shifts character traits in a specific direction
directional selection favors ____ against both average and large individuals of population
small size
directional selection favors individuals at ___ of a distribution range for a trait and selects against ___
one end; average individuals
stabalizing selection
acts against individuals who deviate too far from the average
balanced polymorphisms
2 or more alleles areb maintained in a population because each is favored by a separate environmental force
disruptive selection
adapts individuals within a population to different habitats
disruptive selection favors individuals at ____ of the distribution of a trait and selects ____ average individuals
both; against
What does evolution represent?
significant changes in allele frequencies over time in a population
the evolution of adaptions in different species due to extensive interactions with each other
a group of individuals of the same species found in the same place and time
allele frequency
the relative proportion of each allele of a gene found in a population
gene pool
the total of all alleles of all genes in the population
founder effect
occurs when an isolated population is founded by a small number of individuals, this population may develop allele frequencies that are very different from those of the parent population