Which statement best describes a keystone species?

In the family tree below, people with the recessive trait of attached earlobes are shaded gray.

The sketch shows a rynchosaur, an extinct animal that is known only from fossils. there has been much debate about the classification of these creatures. some scientists suggest that they belong with primitive amphibians, and some think they are related to snakes and lizards. the data equally support both cases. which statement best explains how to draw a cladogram that includes the rynchosaur? draw the cladogram for amphibians. draw the cladogram for reptiles. draw two cladograms, both showing the traits, and leave it as a hypothesis. draw two cladograms, both showing the traits, and have scientists vote

Agenus is a taxonomic grouping that identifies a collection of species. when a scientist discovers a new species, how is this species assigned to a genus