Milkweed and Monarchs

Question

The photo below shows a monarch butterfly on a type of plant called milkweed. Monarch butterflies and milkweed have a very specialized relationship characterized by several benefits.

Monarch butterflies only lay their eggs on milkweed, and monarch caterpillars only feed on milkweed leaves. This means the milkweed is the only host species for the monarch butterfly. In addition to having a place to lay their eggs and a food source for their caterpillar stage, the butterflies also benefit by using the milkweed nectar as a food source. In return, the milkweed plants benefit by getting help with pollination. It is important to note, however, that multiple insects can help pollinate the milkweed, but the milkweed is the only host plant for the monarch butterfly.

Monarch populations are threatened by several factors. One of those threats is the loss of native milkweed plants. As the milkweed population goes down, so does the population of Monarch butterflies.

Adult monarch butterfly on milkweed flowers

Image: A monarch butterfly on common milkweed by Yehyun Kim, Friends of Acadia.

Question 1
The graph below shows the relative abundance of monarch butterflies as compared to milkweed plants. Consider evidence from the graph as well as the passage above. Notice that the butterfly population began to decrease after the milkweed population began to decrease.

5. What reasonable prediction can be made when analyzing the relationship between the milkweed plant and the monarch butterfly?

(1 point)
Responses

The milkweed population has no affect on the monarch population.
The milkweed population has no affect on the monarch population.

If the milkweed population begins to recover and increase, then the monarch population will also begin to recover and increase.
If the milkweed population begins to recover and increase, then the monarch population will also begin to recover and increase.

If the milkweed population continues to decrease, then the monarch population will begin to recover and increase.
If the milkweed population continues to decrease, then the monarch population will begin to recover and increase.

If the monarch population begins to recover and increase, then the milkweed population will eventually go extinct.
If the monarch population begins to recover and increase, then the milkweed population will eventually go extinct.
Question 2
6. Use the choices from the drop down menus to fill in each blank.(4 points)
There is a symbiotic relationship between the monarch butterfly and the milkweed plant. Because the butterfly
and the milkweed
, it is a
relationship. If the milkweed plants were to go extinct, then the monarch butterfly population would eventually
because the butterfly would have nowhere to lay its eggs.

Answer 1

Question 1:

The reasonable prediction that can be made when analyzing the relationship between the milkweed plant and the monarch butterfly is:

If the milkweed population begins to recover and increase, then the monarch population will also begin to recover and increase.

Question 2:

There is a symbiotic relationship between the monarch butterfly and the milkweed plant. Because the butterfly depends on milkweed for survival and the milkweed benefits from the butterfly's pollination, it is a mutualistic relationship. If the milkweed plants were to go extinct, then the monarch butterfly population would eventually decline because the butterfly would have nowhere to lay its eggs.