A plant biologist observed a peculiar pattern when a tropical shrub was attacked by caterpillars. After a caterpillar ate a leaf, it would skip over nearby leaves and attack a leaf some distance away. Simply removing a leaf did not trigger the same change nearby. The biologist suspected that a damaged leaf sent out a chemical that signaled other leaves. How could this hypothesis be tested?

Verified step by step guidance

1. Identify and isolate the chemical suspected to be the signaling molecule released by the damaged leaf. This could involve collecting volatiles or sap from a damaged leaf and analyzing its chemical composition.
2. Design an experiment where some plants are exposed to the isolated chemical, while others are not. Ensure that all other variables are controlled, such as environmental conditions and plant type.
3. Simulate caterpillar damage on a leaf of the test plants by applying the isolated chemical to the leaf, and observe the response of the surrounding leaves in terms of defensive measures like the production of toxins or changes in leaf chemistry.
4. Compare the response of the leaves in the chemically treated plants to those in the control group. Look for patterns such as leaves farther away from the treated leaf showing a heightened defensive response compared to those closer or in the control group.
5. Analyze the data collected to determine if there is a statistically significant difference in the defensive responses of leaves based on their exposure to the suspected signaling chemical. This would help confirm or refute the hypothesis that a damaged leaf sends out a chemical signal to alert other leaves.