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A simplified evolutionary tree (cladogram) shows the relationships among six primate species. Image Description The image shows an evolutionary tree with six primates arranged from left to right: human, chimpanzee, bonobo, gorilla, orangutan, and common gibbon. Each primate is illustrated with a small figure above its name. Below the figures, a branching diagram connects the species. The human branch connects first with a branch shared by chimpanzee and bonobo. This combined branch then connects with the gorilla branch. Further down, these branches join the orangutan branch. All of these branches eventually connect with a deeper branch that leads to the common gibbon. The tree has a step-like structure, with branching points occurring at different depths along a thick, gray vertical line. Question Based on the evolutionary tree shown above, which two organisms are most closely related?

A farmer notices that two of her cotton plants produce cotton with a slight greenish color. Over several generations, she breeds only the greenish plants and eventually develops a variety that consistently produces deep-green cotton without the use of dyes. What type of process is this an example of?

The male peacock’s large, colorful tail helps attract mates but also makes him more visible to predators. What type of evolutionary trade-off does this example best represent?

In a certain fish species, males with bright blue coloring attract more mates but are also more visible to predators. Despite the risk, the bright blue trait remains common in the population. Which evolutionary process best explains the maintenance of this trait?

Darwin drew on multiple lines of scientific evidence to support his theory of evolution by natural selection in On the Origin of Species. From at least three different sub-disciplines of biology (such as paleontology, anatomy, embryology, or ecology), describe the types of evidence he used and explain how each one supports the theory. What are three examples of such evidence, and how does each contribute to the argument for evolution by natural selection?

Many similar-looking but distinct species are found on opposite sides of the Isthmus of Panama. What is the most likely explanation for how these species formed?

In a small population of birds, there are a total of 20 alleles for feather color. If 5 of those alleles code for blue feathers, what is the allele frequency of the blue feather allele in the population?

Choose the sentence that best combines the ideas of the shorter sentences. The date for the lecture has been changed. She did not know that. The new date is February first.

Choose the sentence that best combines the ideas of the shorter sentences. There are new academic rules regarding honesty. The rules were established in January. The rules are considered inadequate by professors.

We must reduce our consumption of natural resources now, before it is too late.