why are the viruses a puzzle for the scientists
Answers
Explanation:
In the past, biologists believed that species were stable and permanent entities and they viewed them as natural kinds which, like the chemical elements, exist in nature independently of any human conceptualization. After Darwin, biologists came to accept that species were the products of evolution and natural selection and were not immutable natural kinds. Different definitions of the species category are discussed, in particular the concept of cluster class as a family resemblance concept. In order to resolve what has become known as the species problem, it is necessary to distinguish between species as concrete entities and species as abstract entities.
Answer:
Because they have to make a medicine for virus..if the medicine have bad side-effects then they have to make other medicine... Then at last they choose one medicine which have not side-effects..