Evolutionary Theory Flashcards
Evolutionary theory: the great chain of being
14th century, creation was a single event, with nearly all species created at nearly the same time; humans are made in the image of god
Evolutionary theory: catastrophism
George Cuvier; 1796; original creation of all species
abrupt changes in fossil record reflect extinctions caused by catastophe; surviving species remained unchanged
Evolutionary theory: Inheritance of acquired Characteristics
Lamarck 1809; animals strive to become perfect during their lifetime, passing advancments off to the offspring
Charles Darwin was originally trained as..
premedicine and theology
H.M.S. Beagle
Darwin’s ship
Darwin was qualified for the job
False
Darwin idolized..
Thomas Malthus
Malthus idea’s
populations can outgrow their resources, and will compete against each other when resources are scarce, thus some individuals will die
combined the concepts of inheritance and competition
Darwin
Galapagos Island finches
resemble mainland finches but are NOT from the mainland
how many species of galapagos finches are there?
over a dozen
Darwins first four theories of evolution
Perpetual change, common descent, multiplication, gradualism;
described observed patterns, did not include mechanisms
Theory of Perpetual change
one of five of Darwin’s theory; the biological world is not static, change of nature is inevitable without a particular direction
Theory of Common Descent
one of five of Darwin’s theories; employs basic tenets of cell theory, life only comes from life, therefore all life on earth is related, more closely related groups have more similarities
Theory of multiplication
One of five of Darwin’s theory; number of species is not constant, one or more species can arise from older ones
Theory of Gradualism
One of five of Darwin’s theory; evolutionary events are very tiny, “baby steps”
changes accumulate over time
earth is very old
Theory of natural selection
Darwin’s fifth theory; answered “how” all his other theories worked. Individuals produce more offspring than can survive and reproduce. All members share the same gene pool. Individuals differ from each other in heritable traits. Different phenotypes result in different levels of reproduction. More successfull contribute their traits to the next generation.
Who else discovered the theory of natural selection?
Alfred Wallace
Difference between Lamarck and Darwin
Lamarcks theory dealt with non heritable acquired traits; Darwin dealt with heritable traits
Micro evolution
Small changes in a species over short time intervals
The birth or death of an individual in a sexually reproducing species
Evolution
Macro evolution
Changes that accumulate over geological time
All of Darwin’s finches are descended from..
The mainland finch
Scientists began looking for missing links:
Archaeopteryx
Two phenotypes of the peppered moth
Pale form white with black speckles
Dark form black with white speckles
What was it itnitially the most common form of peppered moth?
Pale form
Why did the dark form become more popular?
The trees became covered in soot
Selection pressure
Petiscide resistance
What populations are still pesticide resistant?
Colorado potato beetle, and house flies
Staphylococcus aureus causes..
Skin infections ; antibiotic resistant
Difference between today’s corn and wild maize
Today’s corn: fewer ears per plant
Better pest resistance
Greater yield
Natural selections operates on populations or individuals?
Individuals
Evolution happens to an individual or population?
Population
Lamarck said evolution happens at what level
Individual
Driving forces of evolution:
Mutations
Genetic drift
Gene flow
Natural selection
Example of genetic drift
Dad did not pass on y linked genes because he only had daughters
What factors accelerate evolution?
Punctuated equilibria (no constant rate of evolution
Bottlenecks and founder effects
Harsh environmental conditions
Convergent evolution
when two species evolve to be similar but do not have common ancestors
Ex. Ticks, lice , fleas
