The diagram below shows the similar limb structures of a dolphin, a horse, and a bat. Similar bones are highlighted in the same colors.

this is a multiple choice question btw u-u

Which of the following is true about these three species?

All three species have not adapted since their existence.
All three species should be classified within the same genus.
All three species share a distant common ancestor.
All three species evolved over time to best fit unique environments.

"1. it should be, it has been for about 20 years, and it's really not much different in the end than breeding animals to have particular traits. there are always concerns about genetically engineered animals/plants affecting the environment in unexpected negative ways, but i can't think of an example where the fears didn't turn out to be baseless.  

first, as you point out, it would be a great advance in pharmacology, to be able to tailor drugs and their doses to me. the pros involve better medical treatment. the cons involve privacy issues like insurance companies denying coverage to people with genetic risk factors. looking at dna markers wouldn't affect the frequency of genetic diseases, but it would allow detection of them earlier. and ok, actually i suppose that if people used this information to avoid having children with genetic diseases, some might decrease in frequency."

i was thinking 4.0 v hope this