A scientists collects strains of a virus from three different years: 2020, 2021, and 2022. The virus is introduced into populations of lab rats, and the mortality rate is measured for each strain. The rat populations are genetically identical. Mortality caused by the infections is 50% in the case of the 2020 virus, 40% for the 2021 virus and 30% for the 2022 virus; these differences are statistically significant. What conclusion can you draw from this experiment? Virulence has evolved to lower levels. Virulence has evolved to higher levels. Rates have evolved greater resistance to the virus. None of these conclusions can be drawn from these data.

A scientists collects strains of a virus from three different years: 2020, 2021, and 2022. The virus is introduced into populations of lab rats, and the mortality rate is measured for each strain. The rat populations are genetically identical. Mortality caused by the infections is 50% in the case of the 2020 virus, 40% for the 2021 virus and 30% for the 2022 virus; these differences are statistically significant. What conclusion can you draw from this experiment? Virulence has evolved to lower levels. Virulence has evolved to higher levels. Rates have evolved greater resistance to the virus. None of these conclusions can be drawn from these data.

Biology Today and Tomorrow without Physiology (MindTap Course List)

5th Edition

ISBN:9781305117396

Author:Cecie Starr, Christine Evers, Lisa Starr

Publisher:Cecie Starr, Christine Evers, Lisa Starr

Chapter10: Biotechnology

Section: Chapter Questions

Problem 2CT

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