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The echidna is an egg-laying mammal whose body is covered in quills for protection from predators.  The porcupine’s body also is covered in quills for protection, although porcupines are not closely related to echidnas. What is the best explanation for presence of quills in these two species?

EXTRA CREDIT: The scale of nature (Great Chain of Being) viewpoint, in which organisms were arranged by increasing complexity on a ladder-like hierarchy, was proposed by _____ (give the person’s name) in approximately 300 BCE.  Spell carefully.

FILL-IN: Lamarck proposed that giraffe parents lengthened their necks by stretching to reach leaves, then passed their lengthened necks to their offspring. He called his hypothesis “the inheritance of _____________”.  Spell carefully, and give the complete term.

HARDY-WEINBERG CALCULATION: A genetic study based on a sample of 100 dolphins found the following observed genotypic frequencies: f(DD)=0.2, f(Dd)=0.5, and f(dd)=0.3.  What is the frequency of the recessive d allele in this population?

Which of the following statements about the Hardy-Weinberg equilibrium is FALSE?

Convergent evolution results in the evolution of ____ characters, which are traits that evolved independently in relatively unrelated taxa because of adaptation to similar ways of life; the similarity in traits is not due to inheritance of that trait from a common ancestor.

Which of the following is FALSE about cephalization?

What is a vestigial trait? Explain why the existence of vestigial traits is evidence for evolution via natural selection.

Give a brief example of a situation in which it would be beneficial for an animal to have a relatively high surface area to volume ratio, and explain why having the high surface area to volume ratio is helpful in that situation. (1-2 sentences is sufficient, do not write a long paragraph.)

Natural selection: Camels live in dry, sandy deserts.  They have extremely long eyelashes to keep the sand out of their eyes.  Like you practiced in the “synthesis” portion of Homework #2, provide a logical and detailed explanation of how, across generations, a population of camels with very long eyelashes evolved from an ancestral population with normal-length eyelashes due to the process of natural selection.  Apply and define relevant vocabulary.   [Note: Unlike in Homework #2, here you do not need to list the 4 criteria first, just provide the “synthesis” part of the explanation. Your explanation should be clear, complete, and logical so that someone who does not already understand natural selection would be able to understand the process by which long eyelashes evolved in camels.)