Compare the embryos of chickens, humans and fish, and describe in detail how pharyngeal arches show a shared evolutionary past?

  1. Compare the embryos of chickens, humans and fish, and describe in detail how pharyngeal arches show a shared evolutionary past? 2. Explain how reproductive barriers result in the development of different species. 3. Explain what is meant by the statement, evolution does not have a goal. 4. Explain why you would or would not expect evolution to proceed more quickly in a rapidly changing environment. Be sure to address all five agents of evolutionary change in your response. 5. Explain, using the illustrations on page 155 of your text, why penicillin, once a widely used and effective antibiotic, is now no longer effective against penicillin-resistant bacteria.