Understanding the inner lives of animals has always been difficult. The difficulty lies in the research methods. Since the methods used to measure human cognitive ability and intelligence cannot be applied in the same way to animals, researchers have to use a variety of interactive and observational tools to focus on animal behavior.
However, despite the difficulty, understanding the second nature of animals is essential in having a deeper understanding of natural science. In fact, animal intelligence, or animal cognition, has drawn the attention of scientists for the last 4 decades, and it has been showing astonishing results. Studies through various research categories, such as perception, consciousness, memorization, and social behavior, have allowed scientists to have a profound understanding of animal intelligence, thereby leading to results that could contradict our common notions.
From past to recent researches, it has been proven that animals, including elephants, chimpanzees, dolphins, and dogs, are highly intelligent. The animals that break our common notions regarding their intelligence are crows and pigs. They are starting to draw more attention these days with their unexpected high intelligence and sophisticated behavior.
While many people think that pigs are lazy and unintelligent, researchers have discovered that they actually have a cognitive ability higher than dogs and 3-year-old human babies, according to Professor Donald Broom of Cambridge University Veterinary. Pigs, in particular, have great social skills and they are easy to train because of their high level of ‘theory of mind’, which is the ability to attribute mental states to oneself and understand that a difference exists when compared to others. In a study done by an American university, scientists managed to train pigs to solve easy jigsaw puzzles and even play video games – something only primates have been able to achieve in previous researches. Regarding language ability, it has been discovered that pigs have more than 20 different sounds that contain different meanings to be used in different situations.
Corvids, or Corvidae, are a large family of bird species, including crows, ravens, and jays, that are considered as the most intelligent of all birds. Their brain-to-body mass ratio is only slightly lower than humans, but equal to the great apes and cetaceans. Although not all species in the crow family are smart, most of them have excellent memory and problem solving skills. A famous 2009 study in Current Biology showed that rooks, which are members of the Corvidae family that do not usually use tools in the wild, dropped stones in the water to raise the level until they could reach the floating worm, just as how the story goes in Aesop’s Fable entitled “The Crow and The Pitcher”. In addition, a 2014 study in Current Biology showed that crows and corvids can solve problems spontaneously.
From Ancient Egypt to the present era, dogs have been one of the most familiar pets to humans. Why is it that the dogs are considered as a symbol of a partner? The reason is in the canine’s high intelligence. They are aware of their owner's thoughts and then act accordingly in order to curry favor with their owner. Based on their intelligence, one study involved the dog IQ test created by Stanley Coren, who is a canine expert in the University of British Columbia. He said that dogs have an IQ of a 3-year-old child. The finding comes from a language development test and math test. A language test presents that an average dog can learn 165 words, which is similar to a 2-year-old baby's ability. Moreover, the math test proves that they have a basic understanding of arithmetic. They are capable of adding or subtracting by 4 or 5 equations.
The Primate Research Institute of Kyoto University in Japan suggests a surprising study result. A chimp named Ayumu beats a British memory champion in a memory match. The match rule is that the numbers 1 to 9 are blinking in a second. Then suddenly squares will come up and cover the numbers. At this time, the test subject puts screen squares in chronological order by recalling a series of numbers from 1 through 9. Ayumu won the match because the chimp touched the screen for one-fifth of a second. The short-term memory of the apes has another process. Although humans can command all cognitive abilities, apes can only command very few abilities. Apes are not domain-general, but adaptions are restricted to a single goal or activity.