Lesson 1
Gradual change in a species over time is called
evolution
The millions of fossils that scientist have collected are called the _________
fossil record
Scientists compare the __________ bases in the DNA of different species to infer how closely related the species are.
nitrogen
True or False
The more similar the DNA sequences of two species are, the more closely related the species are.
True
Only the organisms with a desired characteristic are bred in
artificial selection
Daily Double
Make a wager (Cannot be more than what you currently have.)
Which term refers to similar structures that related species have inherited from a common ancestor?
Scientists infer evolutionary relationships by comparing the early development of different ________
organisms
Darwin concluded that organisms on the Galápagos Islands
A. were the result of selective breeding.
B. had remained the same.
C. had no variations.
D. had changed over time.
D. had changed over time
Differences between members of the same species are called
variations
Which term refers to a species creating more offspring than can possibly survive?
overproduction
___________ proposes that species evolve slowly but steadily.
Gradualism
True or False
To help him study how species change, Darwin bred pigeons.
True
Which term refers to the process by which individuals that are better adapted to their environment are more likely to survive and reproduce?
Natural Selection
Scientists infer that species with similar body structures and development patterns had a common
ancestor
What can happen when a community becomes isolated from the rest of its species for many generations?
A new species can form.
True or False
Through natural selection, harmful variations gradually accumulate in a species.
False
A trait that helps an organism survive and reproduce is called a(n)
adaptation
How does natural selection lead to evolution?
Helpful variations accumulate among surviving members of the species.
Which term describes the pattern in which rapid changes occur in a species for short periods, followed by a long period of little or no change?
Punctuated Equilibrium
Which of the following sets of factors did Darwin identify as affecting natural selection?
overproduction, variation, and competition