Biology: Concepts and Investigations 2nd Edition by Mariëlle Hoefnagels

Exercise 16

Panspermia suggests that life on Earth developed from primitive "spores" that arrived from outer space. Suppose it did so on multiple planets, eventually giving rise to humans (on Earth) and Star Trek' s Vulcans (on planet Vulcan). In that case, would humans be more closely related to Vulcans or to Earth species such as crabgrass and bread mold? Given your answer, does it seem likely that Star Trek 's Mr. Spock could have had one Vulcan and one human parent?