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Natural Selection
Continuity of Life
Genetic Diversity
Evidence for Evolution
Patterns of Evolution
100
the finches that Darwin observed on the Galapagos Islands evolved into different species in response to...
The types of available food (seeds, nuts, insects)
100
All organisms on Earth today have which two things in common?
1. They have DNA or RNA 2. They have proteins (and the same amino acids)
100
The presence of many different phenotypes in a population is called
variation
100
Humans, whales, cats, and birds have similar bone structure in their limbs. These structures are called
homologous
100
If an environment changes rapidly, and a species which has stayed the same for a long time evolves quickly in response, what is this called?
Punctuated Equilibrium
200
Favorable traits increase in a population over time because...
the individuals with those traits pass them on to their offspring
200
Does asexual or sexual reproduction result in variation among the population?
Sexual reproduction results in variation.
200
a trait is considered "favorable" if it ...
increases the chances that an organism will survive and reproduce (fitness)
200
The immigration or emigration of individuals into or out of a population is called
gene flow
200
A shark and a dolphin have similar body shapes. They do not share a common ancestor - what is this called?
Convergence or Convergent evolution. (or analogous structures)
300
There are four principles of natural selection. What are they?
1. Overproduction of offspring 2. Variation 3. Adaptation 4. Descent with Modification
300
What are the four sources of genetic variation in a sexually reproducing species?
1. random mutations 2. crossing-over 3. gene shuffling 4. recombination of DNA
300
A group of organisms that share a common gene pool and can reproduce with each other is called a ______.
species
300
Whale skeletons have been discovered with a small pelvis and femur bone, which is not used in a whale since it swims in the ocean, insteading of walking on land. These structures are called
vestigial structures
300
When many species evolve from a common ancestor, it is called
Divergence, Divergent Evolution, Adaptive Radiation or Speciation.
400
Why do many organisms produce more offspring than can survive?
Because the competition among offspring means that only the "fittest" organisms will survive; this ensures the continuation of the species
400
T or F: Mutations are always harmful.
False.
400
What would happen to the frequency of a gene allele that increases an organism's attractiveness to mates?
the frequency of that allele would increase over time
400
When looking a phylogenetic tree or cladogram, how do you know which species diverged first and are the oldest?
The species that diverged first will be closer to the BOTTOM of the diagram (closer to the common ancestor)
400
What are the ways that two populations can become isolated from each other?
they can be separated by geography, behavior, or differences in timing or breeding cycles
500
What causes speciation? (the formation of new species)
Natural selection
500
In what type of an environment does an asexual species have an advantage over a sexual sepcies?
an unchanging, stable environment
500
What is the difference between random mating and non-random mating? (give examples)
Random mating is based on chance; the organisms do not "choose" each other based on any type of criteria. For example, two grizzly bears who just happen to be in the same geographical area at the same time will mate. Non-random mating is when an organism selects a mate based on a certain characteristic, such as a female cardinal selecting a male cardinal with the brightest feathers.
500
How can the embryos of fish, turtles, chickens, pigs, rabbits and humans be used to determine which of them are closely related to each other?
Scientists look at the similarities between the embryos; for example if the chicken embryo is more similar to the turtle than it is to the fish, then it provides evidence that birds and reptiles share a common ancestor.
500
The yucca plant is pollinated exclusively by a species of moth that in relies on the yucca for survival. Yucca moths tend to visit the flowers of only one species of yucca plant and pollinate the plants. The yucca plant provides a place for the moth to lay its eggs, deep within the flower where they are protected from any potential predators. This is an example of
coevolution