Traits and Frequencies
If a trait shows no effect on a species ability to survive and reproduce, the frequencies of this trait would ______.
Stay the same, not change etc.
Other than the three types of structures we discusses (homologous, analogous and vestigial) what is the other way we can tell evidence of ancestory?
DNA
What do we call a species becoming better fitted to their environment over time/generations. This is driven by natural selection
Evolution
The ability of an organism to survive and reproduce in its environment is referred to as its...
Fitness
We can tell two species have seperated or undergone speciation because they are no longer able to do what?
Reproduce at all OR reproduce only infertile offspring
If a trait is harmful, we would the frequency of it ______ in a population.
Decrease
These structures are found within species but no longer have a defined purpose. What type of structures are these?
Vestigial structures.
What is one factor that would cause natural selection to occur?
Mutations
Environmental change
This process selects traits that are best suited for an
environment. What is this?
Natural selection
Organisms that share traits and behaviors AND reproduce to create fertile offspring is the definition of?
a species.
What is one benefit for genetic variation within populations?
- different forms of traits
- allows evolution to occur
- survival in different environments
- etc
Humans and dogs have bones in their forelimbs that have the same structures but different functions. What type of structures are these?
Homologous structures.
Certain species of birds choose their mates based on the songs they sing. What type of selection is this?
Sexual Selection.
A change in the DNA code/sequence is known as a ________
Mutation
Mules and Ligers are examples of two species reproducing. The parental species are still two different species because we know Mules and Ligers are what?
Infertile, sterile
A parrot has gained the ability within its life to say the phrase "science rules." This super cool parrot become the mother of some baby parrots but her offspring are not able to say "science rules" on their own, this is because this ability was not passed down to her offspring in their ____?
DNA or Genes
Fish have fins and mammals have flippers. Although these have different internal structures, their function is the same. What type of structures are these?
Analogous Structures.
Dogs have a trait that allows them to bark. The two extremes for the trait is a very loud bark or a very quiet bark. If the bark is too quiet, they cannot alert other dogs but if the bark is too loud, it will make them easier to spot by predators. What type of selection favors traits in the middle of these extremes?
Stabilizing Selection
An inherited behavior or trait that makes an individual better fit for their environment would be an
Adaptation
What type of isolation physical separates populations until they become two different species?
Geographic Isolation?
A new trait is introduced into the human population. In generation 1- 5%
Generation 10- 13%
Generation 20- 37%
What type of trait is this?
Beneficial Trait.
Kiwis are small, nocturnal birds that rely on touch and smell to find their food rather than sight. These birds are unable to fly and move around soley on foot in the forest floors. Kiwis have all of the anatomy of a normal bird BUT have a vestigial structure. What would it be?
Wings
diminutive wings of kiwis
What do we call the type of selection that selects for one of the extremes in a trait?
ex. Long tails over short ones
Directional Selection
What is the definition of inheritance?
The passing of genetic information (Genes, DNA) being passed from parent to offspring over generations
Reproductive Isolation