Question

Female luna moths (Actias luna) attract males by emitting chemical signals that spread through the air. Male hundreds of meters away can detect these molecules and fly towards their source. The sensory organs visible in the photograph are shown here. Each filament of an antenna is equipped with thousands of receptor cells that detect the sex attractant. Based on what you learned in this chapter, propose a hypothesis to account for the ability of a male moth to detect a specific molecule in the presence of many other molecules in the air. What predictions does your hypothesis make? Design an experiment to test one of these predictions.

Short answer

A hypothesis is proposed in the case of the female luna, and male luna is predicted the antennae are responsible for sensing signals. The hypothesis is set to analyze the reaction of luna with and without an antenna.

Step-by-step solution

Description of receptors

The receptors are present on the cell surface to receive signals. The signaling of the cell within the body is communicated via these receptors. The receptor gets activated by the binding of chemical substances or ligands.

Description of insect’s attraction

The male and female insects are attracted to each other with the help of receptors. The unique adaptations of insects are to sense the volatile components present in the air. The sensing of chemical signals is intraspecific chemical signal sensing.

Hypothesis and experiment to study the attraction between the male and female luna moth

Female luna attract the males by releasing a chemical substance called pheromones. The pheromones are released into the air, which is sensed by the antennas of the male moth.

The hypothesis can be framed based on the distance as a parameter. The distance does not influence the sensing mechanism. The male insect can sense the signals from a longer distance.

Another hypothesis is framed based on the antenna present in the male as the parameter. For the experimental analysis, two groups of moths are placed.

The first group is the control group with an antenna, and the other is the experimental group that does not have an antenna. The experimental group will not be able to sense the pheromones without the antennas.

Hence, the second hypothesis is confirmed by conducting the experiments to confirm that antenna is responsible for sensing the signals.