Darwin thought that, if enough time were allowed, what type of selection would modify a population to create a new species?
What is natural selection?
These are anatomically similar structures inherited from a common ancestor, such as the bones in humans, birds and horses.
homologous
This piece of evidence is an early pre-birth stage of an organism's development.
What is an embryo?
This principle states that as long as allelic frequencies remain the same, a population is in genetic equilibrium. There are five conditions for this principle.
What is Hardy Weinberg?
This type of selection eliminates the extreme traits (ie: really tall and really short) and favors the average trait?
What is stabilizing?
What type of selection is another name for selective breeding like how we have developed new dog breeds.
What is artificial selection?
This structure is similar in construction on two different organisms but did not come from the same ancestor. (ex: bird wing and insect wing)
What is analagous?
This piece of evidence is a branch of science that studies the distribution of plants and animals around the world.
What is biogeography?
This is any change in the genetic frequencies of a trait in a population because of chance (it's random!).
What is genetic drift?
This type of selection occurs when nature favors one extreme form of a trait. (ex: Tall, the most tentacles, the darkest color, etc)
What is directional?
Scientists call this changes over time in a group of organisms.
What is evolution?
These structures are remnants of functional structures, such as leg bones in whales and snakes.
What is vestigial?
This is a measurement of survival of the offspring of the organism. (Think, survival of the...)
What is fitness?
This occurs when a small population of a species settles ("founds") in an area and that small population has a frequency of alleles that differs from the larger population.
What is the founder effect?
This type of selection favors the two extremes of a trait and acts against the average form of a trait.
What is disruptive?
This is where Darwin traveled where he explored new species of birds and tortoises.
What are the Galapagos Islands?
These are traits that do appear in the ancestors of an organism, such as mammals having hair/fur.
What is ancestral?
This is an adaptation that allows an organism to blend into its environment.
What is camouflage?
When a population's numbers drop to a very low number then rebound. This causes the gene pool of the rebound population to be similar to that of the population when it was small in number.
What is the bottleneck effect?
The horse becoming much bigger from its ancestors is this type of selection.
What is directional?
This is the book Darwin published discussing his idea on natural selection.
On the Origin of Species
These are newly evolved traits NOT found in ancestors of an organism, such as flightless birds that have lost their abilities to fly.
What is derived?
This trait allows one species to resemble another species through a behavior or physical characteristisc (example, the walking stick)
What is mimicry?
When new genes enter or leave a population, ____ ___ occurs. When mating is non-random and occurs locally, there is little of this. Same when populations are small.
What is gene flow?
Natural selection is different from genetic drift because it is or is not random?
What is NOT random? Remember, survival of the fittest!