How do organisms X, Y and Z move?

Explanation:

three new organisms ,x,y and z were discovered by a group of zoologists they observed that organisms x and y depend on organisms z for food . organisms z does not depend on oraganisms for food . oraganisms x is the . only one that can move on its own

name and explain one of the event that occurs during meiosis that increases the variation in offspring even more than simple reproduction?

in 1859, charles darwin set out his theory of evolution by natural selection as an explanation for adaptation and speciation. he defined natural selection as the "principle by which each slight variation [of a trait], if useful, is preserved".