Darwin's Theory of Natural Selection
Who observed that members of a populating vary in their functional, physical, and behavioral characteristics?
Charles Darwin
If a rabbit has an appendix that they do not use what type of structure is this, and how will it change over time?
The appendix is a vestigial structure and as time goes on the structure will get smaller in size.
If the Hardy- Weinberg conditions are not met, what could occur?
Evolution will occur which is measured by a change in the gene pool frequencies.
If in a species of snail, the large and small size snails survive but the average size does not what type of selection is occurring?
This is disruptive selection.
*Also know directional selection and stabilizing selection*
What is a population and what is an example?
A population is all of the members of a specific species that live in the same area, for example all of the finches on an island.
What theory did Lamarck discover and what would be an example of this theory?
The theory of acquired traits. An example would be a finch copying a woodpecker in order to flush out insects for resources.
Why is comparing embryos not a type of comparative embryology?
Comparative embryology includes homologous structures (shown in common ancestry), analogous structures (not in common ancestor), and embryology. Comparing embryos would be a type of comparative embryology.
If mating is not random, but instead occurs between individuals of the same phenotype what could occur?
There will be an increase in the number of homozygotes in the population.
If male birds with longer tail feathers mate more often, what conclusion can we draw?
The length of the tail feathers is influence by female choice in which birds' mate.
If a population experiences disruptive selection but does not result in assortative mating or two separate species what could be a reason for this?
There is no reproductive isolation between the population
If an individual is fit in their environment, what are they able to do?
They are able to produce surviving offspring in their environment.
If a group of organisms undergoes a founder's effect and then over the years becomes many different species with a variety of adaptations what would this be an example of?
adaptive radiation
If a population is not in Hardy Weinberg equilibrium, what condition can lead to adaptations?
natural selection
If you were studied animals who had similar traits but ancestry does not show a common ancestor what could have occured?
Convergent evolution occurred because the species adapted to have a trait that benefited their survival even though they do not share a common ancestor.
If two species of frogs are found in the similar habitats what could prevent them from interbreeding?
mechanical isolation
If natural selection was acting on an organism, why would organisms have random variations?
Organisms' variation in traits can come from mutations in their DNA, so in order for them to have random variations they must inherit the variations from generation to generation.
If a population in large, what could be one factor for genetic change?
The organisms will be competing for limited resources.
If there is gene flow between two populations of the same species, what would occur?
The two-population swill become more genetically similar.
If a male bird loses its tail feathers after mating season, why would this be an example of a cost- benefit analysis?
The long tail feathers require more energy to produce and more energy to fly which means they will lose the feathers when they are no longer needed.
What is the difference between gradual and punctuated equilibrium?
Gradual occurs gradually and slowly over a period of time whereas punctuated equilibrium occurs from rapid periods of change following long periods of no change.
If Darwin was looking at bird beak data and saw that during dry years the depth of bird beaks increased, what could be a conclusion he made?
A drought caused the seeds to become hard to open and hard to eat for small beak birds.
When comparing the cytochrome c amino acid sequences there are only 51 differences between yeast and humans, if this is the case what can by suggested?
The structure of important proteins is highly conserved in evolutionary history.
What is the difference between a founders effect and bottleneck and what is an example of each?
Founders effect is when a small portion of the population leaves the main population and starts a new population. An example would be Darwins finches finding each island. A bottleneck is when a natural disaster removes a large portion of the population. An example would be a tsunami.
What are postzygotic and prezygotic isolating mechanisms?
Postzygoic are isolations that occur after mating.
Prezygotic are isolations that prevent two species from interbreeding.
What is the biological species concept and evolutionary species concept?
Biological- The members of a species a have a single gene pole due to reproductive isolation.
Evolutionary- relies on the identification of morphological traits to indicate different species