Edward jenner’s smallpox inoculation experiment was based on an observation by a dairymaid that she could not get smallpox because she had already had cowpox. how did jenner form his hypothesis from this observation?

Ascientist observes certain changes in the physical features of a particular species over time. she concludes that the species has undergone evolutionary change. she wants to study the animals by analyzing their population. she’ll use . the population of this species is decreasing considerably. if this trend doesn’t change, this species will fall under the category of animals. this is a plato question,i need to make up his biology credit.