Answer
An extinct high-altitude mammal could resemble both the lowland South American mammals and the high altitude African mammals. It would resemble the former based on descent from a common South American ancestor, but it could resemble the latter due to convergent evolution driven by similar selection pressures at high altitude.
Work Step by Step
Skim this chapter for information on convergence, and review earlier material on genetics to see that conserved mechanisms such as homeotic genes would tend to preserve similarities with nearby relatives having a common ancestor.
