What is a shared derived characteristic? What is an example of this type of characteristic? (20 points!!)

Shared derived characters can be used to group organisms into classes.

Explanation:

For example, amphibians, turtles, lizards, snakes, crocodiles, birds and mammals all have, or historically had, four limbs.

your answer is "the 1950's"

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.