The Scientist who had developed IQ test for animals and how it works.

There have been several scientists who have developed IQ tests for animals, but one of the most well-known is Dr. Marian Diamond, a neuroscientist at the University of California, Berkeley.

Dr. Diamond developed a test that measures the intelligence of rats by observing their ability to learn and remember the location of food rewards in a maze. The rats are placed in a maze and must navigate to find a food reward. The maze is then altered to see if the rats can still find the food reward. The test measures how quickly the rats learn the maze and how well they remember it.

Other researchers have developed similar tests for other animals, such as chimpanzees, dolphins, and dogs. These tests usually involve tasks such as problem-solving, tool use, and memory tasks, and are designed to measure an animal's cognitive abilities and intelligence.