MISSION 5 — Dawn of a Modern Pandemic
Viruses are strange, and the more we learn about them, the stranger they seem to get. Considered by many as not quite an “organism” because they can’t reproduce outside of a host or generate their own energy, viruses are everywhere—on every surface and inside every living thing. Contrary to what most people think, however, many viruses are harmless. Some are likely even helpful! HIV, however, is not harmless—at least not to humans. Where did it come from? Figuring that out is your job in this level.
Play "Dawn of a modern pandemic" and answer questions 11–15 after you've completed the level.
11. A Cameroonian woman living in Paris was the first to be diagnosed with HIV-1 P in 2009. Which ape virus is most closely related to HIV-1 P?
12. Click on the button below to answer question 12. Remember to refer to your completed tree and the species comparison tab if you are not sure of your answer.
13. How do scientists think that SIV has jumped hosts to humans?
14. Based on your completed phylogenetic tree, how many times—at a minimum—do you infer that an HIV virus has jumped hosts to humans? Explain your answer.
15. Viruses such as HIV reproduce rapidly. What is the connection between reproduction rate and evolution?
