Jon Sullivan/pdphoto.org, Wikimedia Commons
Creatures both big and small made the list of the top 10 most intelligent organisms on the planet, proving that bigger isn't always better when it comes to brains. The new list, created by neuropsychiatristJon Lieff
, includes animals that have been widely known for their smarts, as well as some surprising entries. Boston-based Lieff, who is a past president of the American Association for Geriatric Psychiatry, specializes in the interface between psychiatry, neurology, and medicine. Such interdisciplinary research is leading to a better understanding on how human and other mammal brains age, which may shed light on treatments for common disorders, such as dementia. Included on the list are bees, which Lieff said use symbolism and abstract concepts to solve problems in their daily lives. "They have a kaleidoscopic memory of every flower for miles, and learn from wise elders where the best flowers are," he told Discovery News. "Bees self medicate in their hives in different ways, and engineer the very complex honeycomb structures that are the most efficient possible for honey storage."Faces of Bees, Flies and Friends: Photos
Do not let their squishy tentacles fool you. Octopuses are extremely intelligent, according to Lieff, who explained that they spread cultural information, mimic others and communicate using colors, patterns and flashing. "They have advanced spatial learning capacity, navigational abilities and use creative predatory techniques," he added. "They manipulate objects as well as the human hand does."Why Octopuses Don't Tie Themselves in Knots
Elephants have highly evolved social capabilities and often show wise, compassionate and loving behaviors, Lieff said. Elephants have amazing memories and can remember friends and enemies for a half century or more, depending on their health and lifetime. (Elephants in the wild can live to about 60, and the oldest known elephant on record -- in captivity -- reached the age of 86.) "In captivity, elephants have become excellent artists," Lieff said. "Elephant communication is elaborate involving many different vocalizations, and they 'speak' to family five miles away. Elephants are extremely collaborative, consoling and cooperative, and deeply mourn their dead."Elephants Outwit Humans During Intelligence Test
Steve Jurvetson, Wikimedia Commons
Ants are the ultimate team players, but they display great individual intelligence as well, according to Lieff. The insects can navigate long distances with ease, remembering their lengthy routes. "Ants care for their family similar to many mammals and show altruism for comrades," Lieff said, mentioning that ants are the second society on earth (after termites) to develop agriculture. Human-established agriculture evolved much later.New Ant Species Hides in Plain Sight Like a Spy
NASA, Wikimedia Commons
Dolphins continue to astound researchers. These marine mammals in captivity can remember the communications of their fellow tank mates for at least 20 years, according to Lieff. "They also immediately notice themselves in a mirror, and are very creative in inventing new ways to fish," he continued. "They wear sponges on their noses to protect themselves near rocks. They have advanced social relations with humans, such as herding large schools of fish toward fishermen wading in the water with nets. When the fish are about to come in contact with the nets, the dolphins signal the fishermen by slapping the water."Dolphins: Second-Smartest Animals?
Birds are among the smartest of animals, with two groups making this particular list. The first are crows. "Crows are aware of themselves and are able to use counting and analogies," Lieff said. "They can solve higher-order, relational-matching tasks spontaneously. They use tools better than most (non-human) primates, molding wire into a hook and using three different tools for one task." He added that studies reveal crows understand the Archimedes principle, which holds that the upward buoyant force exerted on a body immersed in a fluid, whether fully or partially submerged, is equal to the weight of the fluid that the body displaces. This knowledge allows crows to manipulate water levels to access food.10 Surprising Facts About Animal Intelligence
Curious and playful, cockatoos are also incredibly smart. Lieff explained that cockatoos use multi-step techniques to solve problems, such as figuring out how a complex cage lock works. For example, Lieff said one clever cockatoo figured out a lock that required removal of a screw, followed by removal of a bolt, then turning a wheel 90 degrees before finally shifting a latch sideways. Other cockatoos that watched this happen quickly repeated the successful maneuver. A quick search at YouTube also reveals that cockatoos "completely disprove the notion that animals can't dance," Lieff said.Cockatoos Watch and Learn From 'Teacher' Birds
Lizards do not get a lot of recognition for their intelligence, but Lieff believes it is time they did. Anole lizards, in particular, continue to impress researchers with their cognitive skills. Anoles demonstrate counting, advanced learning and problem solving, he said, adding that their memories are extraordinary. In captivity, these lizards can "invent techniques that they don't use in the wild. They can use multiple different strategies (to solve puzzles) and can unlearn incorrect approaches, rapidly reversing course."Lizard Penises Evolve at Super-Speed
Dogs are so loyal to humans that they often don't get credit for their own intelligence. "From a purely cognitive vantage point, dogs have learned up to a thousand different words," Lieff said. He added that "service dogs demonstrate creativity and high intelligence" in saving others. Canines can also accurately read human emotions.Dogs Understand Human Smiles, Scowls
Whit Welles, Wikimedia Commons
Rounding out the list are whales, which demonstrate elaborate communication techniques and cultural exchange. "They work together for creative fishing techniques, with each whale in a designated role," Lieff said. For example, he explained three whales sometimes line up in a row while beating their tails together. This creates waves that can knock a seal off an ice perch. Whales also swim beneath a school of fish in circles, blowing air bubble "nets," which trap the fish. This requires a lot of team organization, as some whales do the diving while others make calls in order to herd the fish. Such teamwork is passed on to other generations.Mystery of Baleen Whale's Hearing May Be Solved
Missing from this Top 10 list are humans and other primates, which clearly excel at social communication, cooperation, tool making and much more. But can a species measure with complete accuracy its own intelligence compared to that of other animals? It's near impossible, since that judgment can only be based on the particular animal's values, brain structure and way of thinking.Can Intelligence Really Be Measured?
Young children and wild great apes think alike, at least when it comes to using tools to solve similar problems.
Since toddlers can come up with their own simple tool techniques, without the help of adults, a new study counters the widespread belief that such basic skills require instruction from adults, or result from copying them. The same is likely true for non-human great apes like chimpanzees too, suggests the research in Proceedings of the Royal Society B.
"We do not fully rely on our cultures to be smart," senior author Claudio Tennie told Discovery News, explaining that "these behaviors instead derive from a complex interaction of genetic and environmental factors," which have yet to be completely determined.
Tennie and his colleagues from the University of Birmingham recruited 50 boys and girls, aged 2.5 to 3 years old, for the study. The researchers created a dozen tasks that were all based on wild great ape natural behaviors. For example, the kids were given a stick, and had to figure out how to retrieve Play Doh balls from a tube. This is similar to how chimpanzees use sticks to pound the bottom of a hole to obtain insects.
Another task required the toddlers to use a wet stick to collect polystyrene beads, and then wipe them into a box. Chimps do something very similar when collecting and then eating ants.
The kids only failed one experiment: the "nut-hammer task," where a plastic sphere serving as an artificial nut had to be cracked open by hammering it with a hard object made of clay. Chimps use rocks as hammers for this purpose. Only one child was able to pull off the task.
For all of the other tasks, however, the kids used their tools in ways that mirror tool use among great wild apes. Lead author Eva Reindl explained that her team chose to study only young children "because with increasing age, children's cultural knowledge will increase, and thus it becomes harder and harder to rule out that children have used cultural knowledge to solve these tasks."
As for why both wild great apes and young humans spontaneously use tools in similar ways, the answer seems to be that both groups are able to learn physical rules governing their environment when interacting with objects.
Orangutans, chimps, bonobos, gorillas and humans all seem to independently figure out the basic rules that they can then apply later to other challenges. For example, if a chimp learns that a stick can retrieve a certain object, then he may use the stick later to acquire other objects.
A chimp uses a twig to capture termites from a mound.Corbis
Interestingly, another recent study, published in PLOS ONE, showed that dogs appear not to have this learning skill.
"That's practical for us, in a way, as otherwise we would need to padlock their food in the kitchen," Tennie said.
Corsin Müller from the University of Veterinary Medicine Vienna led the study on dogs. He told Discovery News that "when it comes to understanding how a particular task can be solved, what dogs learned when solving previous tasks does not seem to help them solving other tasks with similar underlying physical rules."
"Of course, dogs do remember something about what led to success in the past (for example, a food reward)," Müller continued. "No dog training would be possible otherwise."
Yet he said dogs in his study could not successfully apply underlying physical rules from one task to other different ones. Great apes do this with ease.
Over time, humans are able to accumulate tool-using skills, far exceeding the abilities of wild great apes. Reindl's team, as well as other research groups, have proposed several key cognitive factors that allow to reach more sophisticated tool-related behaviors that include everything from manipulating a cell phone to driving a car.
"These factors include the ability to innovate; high-fidelity social transmission mechanisms such as imitation, active teaching, and language; cooperative tendencies -- as well as the capacity of frequently copying several sources of information at once," Reindl said.
She added, "One of the key differences that our team has identified is the relative lack of imitation, as well as the lack of teaching in non-human great apes. But it surely does not help either that they do not talk."