In the Oxford lab experiment, the New Caledonian crow (Betty) used wire—an unfamiliar, artificial material—and "bent the wire into a hook to retrieve the meat." 3. B (Western Scrub-Jay)
: The IELTS Reading test is timed, so practice is essential. Spend about 20 minutes per passage. If you're stuck on a question, move on and come back to it if you have time.
Corvids can recognize individual human faces and "hold grudges" against researchers who have previously bothered them. Memory & Caching: They can remember the locations of hundreds of food caches
Paragraph B focuses on the New Caledonian crow solving "multi-step puzzles that require using a short tool to retrieve a longer tool." The word "instruments" in the question acts as a synonym for "tools." In the Oxford lab experiment, the New Caledonian
Recognizing individual human faces is another extraordinary survival mechanism developed by urban corvids. A landmark study conducted at the University of Washington involved researchers wearing distinct, threatening latex masks while capturing and banding wild American crows. Years after the initial capturing event, the crows continued to scold and mob individuals wearing that specific mask, while completely ignoring neutral control masks. This hostile response was passed down to offspring and spread to neighboring crows who had never been captured themselves. This cultural transmission of information demonstrates that corvids possess advanced communication networks, allowing critical survival data regarding specific environmental threats to propagate through generations without direct personal experience. Paragraph G
Paragraph D explains how scrub-jays track when they hid food, specifically avoiding perishable worms once they have had time to decay. 5. i (Anatomical differences and evolutionary surprises)
: The text often compares bird intelligence to that of humans or primates (e.g., "chimpanzees"). Pay attention to these to answer multiple-choice questions correctly. Check the Location If you're stuck on a question, move on
Scientists have always known that birds possess a highly advanced neurological structure.
: When the same researchers walked around without the masks, the crows showed no reaction, confirming they were specifically identifying the face as the threat.
— Most researchers assume this tool use is cultural rather than instinctive. A landmark study conducted at the University of
The study of corvids helps scientists understand the evolution of intelligence. It proves that a large, complex brain is not the only path to high-level cognition. The dense neuronal structure of the avian brain suggests that the efficiency of neural connections is just as crucial as the absolute size of the brain. 5. Summary Table for Quick Revision Intelligence Aspect Tool Manufacturing Shaping twigs into hooks [3]. Raven Problem Solving Using multiple tools sequentially [2]. Scrub Jay Future Planning Caching food based on anticipated hunger [2]. All Corvids Social Memory Hiding food,, remembering locations [1]. Conclusion
: Always pay close attention to the instructions for each set of questions. For example, in the True/False/Not Given questions, note the specific instructions: ' TRUE if the statement agrees with the information, FALSE if the statement contradicts the information, NOT GIVEN if there is no information on this'.
In an IELTS Reading test, passages on animal intelligence often focus on and results . You will likely encounter: