Type 3: Ambiguous Figures 🔴 Hard
Duck or Squirrel?
A modern classic of ambiguous figures where a single contour represents completely different animal shapes depending on which end you focus on.
👁️
👁️ WHAT TO LOOK FOR: Stare at the image. Use the toggles below to highlight the contours that define the duck (facing left, beak at the top-left) or the squirrel (facing right, tail on the right).
🎮 EXPERIENCE IT FIRST
Observe how your brain resolves this visual ambiguity:
- When you first look at the image, which animal did you see? For most, top-down priming determines the winner.
- Try focusing on the left protrusion (the beak/snout) vs the right protrusion (the wing/tail). Notice how the entire animal shape swaps in your awareness.
- Can you consciously force your brain to perceive both at the exact same moment? Cognitive science shows this is impossible.
🧠 THE SCIENCE
The Duck or Squirrel optical illusion is a prime example of an ambiguous bistable figure. In this illusion, the human visual system is presented with conflicting visual information. The contour lines are mathematically shared between two potential objects. Specifically, the curves representing the duck's beak on the left also represent the snout and paws of a squirrel. Conversely, the large wing shape on the right doubles as the squirrel's classic bushy tail.
When light enters the eye and hits the retina, it triggers neural impulses that travel to the primary visual cortex (V1). V1 extracts basic contours, edges, and orientations. However, V1 alone cannot determine whether the drawing is a duck or a squirrel. This high-level task is performed in the temporal lobe, specifically the lateral occipital complex (LOC), which is responsible for object recognition. The LOC compares the shape against semantic templates stored in memory.
Because both templates (duck and squirrel) match the physical contours perfectly, the brain faces a dilemma. It resolves this through neural competition: when one interpretation is active, it actively inhibits the other. This prevents you from seeing both animals simultaneously. The spontaneous switching between the two interpretations, known as bistable perception, is driven by neural fatigue. As the neurons coding for the "duck" interpretation grow tired, the competing "squirrel" neurons take over, flipping your conscious perception.
💡 FUN FACTS
- • Less than 40% of viewers can spontaneously spot both animals without being told what they are.
- • Bistable art like this is used by cognitive researchers to study how consciousness shifts without any change to the physical stimulus.
- • Gaze direction heavily dictates the winner: looking at the left side primes the duck, while looking right primes the squirrel.
🧪 TRY THIS AT HOME
Show this image to a friend. Ask them to describe what they see. If they see a duck, tell them "look at the squirrel's tail on the right." Watch how long it takes for their visual cortex to re-organize the shapes!
📜 DISCOVERER
Creator: Modern Bistable Artists
This drawing is a modern evolution of the classic Jastrow Duck-Rabbit. While Jastrow focused on simple orientation shifts, the Duck-Squirrel integrates complex interlocking silhouettes to challenge figure-ground segmentation.