#Question id: 4569
#XL - S Microbiology
Which of the following must exist in a population before natural selection can act upon that population?
#Question id: 4570
#XL - S Microbiology
Which pair would probably have agreed with the process that is depicted by this tree?
#Question id: 4571
#XL - S Microbiology
Evolutionary trees such as this are properly understood by scientists to be
#Question id: 4572
#XL - S Microbiology
Of the following anatomical structures, which is homologous to the wing of a bird?
#Question id: 4573
#XL - S Microbiology
Which of the following pieces of evidence most strongly supports the common origin of all life on Earth?
#Question id: 4574
#XL - S Microbiology
Ichthyosaurs were aquatic dinosaurs. Fossils show us that they had dorsal fins and tails, as do fish, even though their closest relatives were terrestrial reptiles that had neither dorsal fins nor aquatic tails. The dorsal fins and tails of ichthyosaurs and fish are