Fill in the blank a scientist 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(blank) answer choice( a. quadrat sampling b. points count c. area searches) the population of this species is decreasing considerably. if this trend doesn’t change, this species will fall under the category of (blank) (a. endangered b. safe c. extinct) animals.