The following passage is adapted from an article about animal behavior.
[Paragraph 1]
New Caledonian crows are famous for their remarkable ability to manufacture and use tools. In the wild, these birds select twigs, strip away their leaves, and shape them into hooks to extract insects from deep crevices in tree bark. This sophisticated behavior shows a level of problem-solving once thought unique to primates.
[Paragraph 2]
To understand how these crows acquire this skill, researchers conducted studies on juvenile birds. They discovered that young crows are not merely copying their parents. Instead, they possess an instinctive predisposition to handle sticks, which is then refined through practice and social learning. This combination of genetic heritage and trial-and-error learning allows the species to pass tool-making techniques down through generations.
[Paragraph 3]
While tool use is a key survival strategy, it also influences the crows' physical evolution. Scientists have noted that New Caledonian crows have unusually straight bills compared to other crow species. This straight shape allows them to hold tools securely and keep both eyes focused on the tip of the tool, showing how behavior can shape anatomy over evolutionary time.
Based on the passage, which primary main idea matches each paragraph?
- Paragraph 1Crows demonstrate complex problem-solving abilities by constructing and employing tools for foraging.
- Paragraph 2The acquisition of tool-making skills in young crows relies on both inborn tendencies and interactive learning.
- Paragraph 3The regular use of tools by crows has driven evolutionary changes in their physical anatomy.