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You are given a group of organisms that includes a: Colorado Blue Spruce tree, Desert Spadefoot Toad Brook Trout Red-Tailed Hawk Black Bear Draw a phylogenetic tree on your paper that reflects evolutionary relationships. Label each “branching event” (both sides) with the shared characteristic that was used to make your decisions.  Upload a photo of your tree.

A young male baboon leaves the troop that he was born in and joins a small neighboring troop of small baboons. He quickly rises to become a dominant male. From an evolutionary point of view, what important process has occurred? 

How does the founder effect influence the frequency of alleles in a population?

If the weather in Virginia changed so dramatically that there was snow on the ground most of the year, what would occur in the local squirrel population?

 The X-linked varieties of congenital stationary night blindness (CSNB) causes myopia (near sightedness), impaired night vision, reduced visual acuity, and other symptoms. A normal man (whose father has CSNB) marries a normal woman (whose father also has CSNB). If you were only looking at male offspring, what is the chance that a SON will have CSNB? (For the purposes of this question, if there are 2 of the same allele letter, place alleles with a linked trait second.) [chance] chance that a SON will have CSNB. [dad1] [dad2] [mom1] [FA] [FB] [mom2] [FC] [FD]

Dandelions in a lawn that is mowed have short flower stalks, whereas those in a field have tall flower stocks. This illustrates:

DNA replication is controlled by enzymes. 1)____________“unzips” the double helix by breaking hydrogen bonds, 2)___________ adds new nitrogenous bases to the exposed single strands, and 3) ____________ bonds short sequences together that are formed from the lagging strand (the strand that is “read” in the opposite direction).

In the karyotype of a person with Down syndrome, or trisomy 21, an extra copy of chromosome 21 is apparent. This abnormality affects roughly 1 of every 700 children born and is the most common serious birth defect in the United States. People affected by Down syndrome often have cognitive difficulties, heart defects, and shortened life spans. Based on this scenario and your understanding of meiosis, what is the most likely explanation for the extra chromosome 21 in people with Down syndrome? 

Assume it is possible to remove continuous cores of rock from Earth that are 3,000 feet long and contain fossils. What would the theory of evolution by natural selection predict about the fossils found in such cores as they are examined from top to bottom?

What is the ratio of expected phenotypes in the offspring produced by the cross Aa × Aa? Assume complete dominance for the trait.