Why are there more species in Family Ursidae than there are in Genus Ursus?

1. which of the following is correct regarding opiates/opioids: a. they all have a natural component as a starting pointb. they have low addiction possibilitiesc. methadone binds to some of the same receptorsd. a and care correcte. all are correct

2. given that most biochemical (other than coal) rocks react with hydrochloric acid, what does that tell you about organisms?

Which is one example of a phenotypic change that is not genetic