Statement I: The Monarch butterfly is highly distasteful to its predator (bird) because of a special chemical present in its body.

Statement II: The butterfly acquires this chemical during its caterpillar stage by feeding on a poisonous weed.

Both statement I and II are correct.

The correct answer is Option (3) -Both statement I and II are correct.

Statement I: The Monarch butterfly is highly distasteful to its predator (bird) because of a special chemical present in its body.

Explanation: This statement is true. The Monarch butterfly possesses a special chemical defense mechanism that makes it unappealing or even toxic to potential predators, such as birds. This defense mechanism is known as "aposematism." The chemical responsible for the distastefulness is called cardenolides, which are cardiac glycosides. These compounds are synthesized by milkweed plants, which are the primary food source of Monarch caterpillars.

Statement II: The butterfly acquires this chemical during its caterpillar stage by feeding on a poisonous weed.

Explanation: This statement is also true. Monarch caterpillars feed exclusively on milkweed plants, which contain toxic chemicals called cardenolides. These cardenolides are ingested by the caterpillars during their feeding on the milkweed leaves. The caterpillars are able to sequester and store these chemicals in their body tissues, making them unpalatable and potentially toxic to predators.

The acquisition of cardenolides from milkweed plants during the caterpillar stage is crucial for the Monarch butterfly's defense against predators throughout its life cycle. The toxic chemicals ingested by the caterpillar are retained and carried into adulthood, providing protection against predation by birds and other potential predators. This chemical defense mechanism serves as a warning signal to predators, indicating that the butterfly is unpalatable or potentially harmful if consumed. As a result, predators learn to associate the distinct visual appearance of Monarch butterflies with a negative taste or potential toxicity, leading to avoidance behavior and reduced predation pressure on the species.