Fox.

The old saying “as smart as a fox” has firmly established itself in our everyday language. Foxes, with their cunning eyes and graceful movements, have colonized the human imagination as emblems of cunning and sagacity. But how do you measure the intelligence of a fox? While we can't directly have foxes take a traditional human IQ test, we can test them on skills similar to components of such tests, such as problem solving, memory, and adaptability. That said, it's important to approach with a healthy dose of skepticism how accurately such tests actually measure a fox's 'intelligence'.

IQ Test Problems for Foxes

1. Food Search Test: Hide food under one of three upside-down cups while the fox watches. See if the fox can remember which head the food is hidden under.
2. Detour task: Place a treat behind a transparent but solid obstacle. Can the fox navigate around the obstacle to get to the treat?
3. Puzzle box: Put a piece of food in a simple puzzle box. Can the fox open the box to get to the food?
4. Hide and Seek Test: Hide food while the fox isn't looking, then let him search. Test the fox's ability to remember and search strategically.
5. Mirror task: Use a mirror to reveal a hidden treat. Does the fox understand that the image in the mirror indicates the location of the food?
6. Changed Cues: Train the fox to find food under a colored object. Then change the color of the object that represents the food. Can the fox adapt to the new cue?
7. Numerical Competence Test: Let the fox choose between two groups of treats, one group with more than the other. Does the fox understand the concept of 'more'?
8. Sequential Task: Hide food in different boxes that need to be opened in a certain order. Can the fox remember the order and solve the problem?
9. Object Permanence Test: Hide an object while the fox watches, and see if the fox can find it.
10. Social Learning Assignment: Show a trained fox how to perform a task to get a reward. Can another fox learn by observation?

While these can be fun experiments, we must remember that testing animal intelligence is a complicated field and these tests may not fully reveal the breadth and depth of a fox's cognitive abilities. For example, a smart fox in the wild may be successful because of its excellent ability to adapt to new environments and challenges, which can be difficult to measure in a laboratory setting.