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 . The population of this species is decreasing considerably. If this trend doesn’t change, this species will fall under the category of animals.

Taking that this question has been posted by other users in Brainly and with the answer choices for it, to fill in the blanks appropriately, the answers to it would be as follows:

1. She wants to study the animals by analyzing their population. She´ll use the quadrat sampling. The reason for this is that this method allows the scientist to study the biodiversity, by using small quadrats where populations of the species being studied can be found. This researcher will place a series of squares and within them she will see samples of the species she is looking for.

2. The population of this species is decreasing considerably. If this trend doesn´t change, this species will fall under the category of endangered animals. This is because although the reduction in numbers is great, there are still enough numbers to not consider the species as extinct.