Aphids are Hemiptera that suck phloem liquid from plants. Ants are often seen tapping the posterior end of the aphid and collecting the liquid that is released from the aphid's digestive system. In an effort to understand this interaction, several researchers measure the survival rates of aphid populations when ants were present and when they were excluded. Their results are shown.
Imagine that you wished to discover if the ants protect the aphids from flying predators. You would exclude ants from the plants and count aphid population size under two conditions. Which of the following experiments would best help answer this question?
A) plants covered by netting versus not covered by netting
B) plants with stems coated at the base with a sticky substance versus not coated with a sticky substance
C) plants with extra fertiliser and water versus no extra fertiliser and water
D) plants sprayed with insecticide versus not sprayed with insecticide

Question

Aphids are Hemiptera that suck phloem liquid from plants. Ants are often seen tapping the posterior end of the aphid and collecting the liquid that is released from the aphid's digestive system. In an effort to understand this interaction, several researchers measure the survival rates of aphid populations when ants were present and when they were excluded. Their results are shown. 
Imagine that you wished to discover if the ants protect the aphids from flying predators. You would exclude ants from the plants and count aphid population size under two conditions. Which of the following experiments would best help answer this question?
A) plants covered by netting versus not covered by netting 
B) plants with stems coated at the base with a sticky substance versus not coated with a sticky substance 
C) plants with extra fertiliser and water versus no extra fertiliser and water 
D) plants sprayed with insecticide versus not sprayed with insecticide

Quizplus · Accepted Answer

By comparing the aphid population size on plants covered by netting (which would prevent flying predators from reaching the aphids) versus plants not covered by netting, we can determine if the presence of ants affects aphid survival in the face of flying predators. The other experimental conditions do not directly address the impact of ants on aphid protection from flying predators.

Aphids Are Hemiptera That Suck Phloem Liquid from Plants