In the classification hierarchy, which group — class or genus — has fewer members but more features in common? Explain your answer.

A genus has fewer members but more features in common than a class. The classification hierarchy proceeds from:

Kingdom → Phylum → Class → Order → Family → Genus → Species.

As one moves from higher (broader) groups to lower (more specific) groups, the number of organisms in each group decreases while the number of shared characteristics increases. A class is a broader grouping that includes many orders, families and genera. Genus is a much more specific grouping that contains only closely related species. For example, the genus Panthera includes only lions (Panthera leo), tigers (Panthera tigris), leopards, and jaguars. The organisms that share a large number of structural, behavioural, and genetic features in common. Therefore, genus has fewer members and more features in common than class, reflecting the principle that lower taxonomic groups are more exclusive and more specific in their shared characteristics.