Bird intelligence deals with the definition of intelligence and its measurement as it applies to birds. The difficulty of defining or measuring intelligence in non-human animals makes the subject difficult for scientific study. Anatomically, birds (the 10,000 species of which are the direct living descendants of, and so are, theropod dinosaurs) have relatively large brains compared to their head size. The visual and auditory senses are well developed in most species, while the tactile and olfactory senses are well realized only in a few groups. Birds communicate using visual signals as well as through the use of calls and song. The testing of intelligence is therefore based on studying the responses to sensory stimuli.
Bird intelligence has been studied through several attributes and abilities. Many of these studies have been on birds such as quail, domestic fowl and pigeons kept under captive conditions. It has, however, been noted that field studies have been limited, unlike those of the apes. Birds in the crow family (corvids), and parrots (psittacines) have been shown to live socially, have long developmental periods, and possess large forebrains, and these may be expected to allow for greater cognitive abilities.
Counting has been considered an ability that shows intelligence. Anecdotal evidence from the 1960s has suggested that crows may count up to 3. Researchers however need to be cautious and ensure that birds are not merely demonstrating the ability to subitize, or count a small number of items quickly. Some studies have suggested that crows may indeed have a true numerical ability. It has been shown that parrots can count up to 6,. and crows can count up to 8.
In the 1970s, on the Li River, Pamela Egremont observed fishermen who allowed the birds to eat every eighth fish they caught. Writing in the Biological Journal of the Linnean Society, she reported that, once their quota of seven fish was filled, the birds "stubbornly refuse to move again until their neck ring is loosened. They ignore an order to dive and even resist a rough push or a knock, sitting glum and motionless on their perches." Meanwhile, other birds that had not filled their quotas continued to catch fish as usual. "One is forced to conclude that these highly intelligent birds can count up to seven," she wrote.
Many birds are also able to detect changes in the number of eggs in their nest and brood. Parasitic cuckoos are often known to remove one of the host eggs before laying their own.
Visual or auditory signals and their association with food and other rewards have been well studied, and birds have been trained to recognize and distinguish complex shapes. This is probably an important ability that aids their survival..
A common test of intelligence is the detour test, where a glass barrier between the bird and an item such as food is used in the setup. Most mammals discover that the objective is reached by first going away from the target. Whereas domestic fowl fail on this test, many within the crow family are able to readily solve the problem.
Large fruit-eating birds in tropical forests depend on trees which bear fruit at different times of the year. Many species, such as pigeons and hornbills, have been shown to be able to decide upon foraging areas according to the time of the year. Birds that show food hoarding behavior have also shown the ability to recollect the locations of food caches. Nectarivorous birds such as hummingbirds also optimize their foraging by keeping track of the locations of good and bad flowers. Studies of western scrub jays also suggest that birds may be able to plan ahead. They cache food according to future needs and risk of not being able to find the food on subsequent days.
Many birds follow strict time schedules in their activities. These are often dependent upon environmental cues. Birds also are sensitive to day length, and this awareness is especially important as a cue for migratory species. The ability to orient themselves during migrations is attributed to birds' superior sensory abilities, rather than to intelligence.
The mirror test allows scientists to determine whether birds are conscious of themselves and able to distinguish themselves from other animals by determining whether they possess or lack the ability to recognize themselves in their own reflections. Mirror self-recognition has been demonstrated in European magpies, making them one of only a few species to possess this capability.[2 However, in 1981, Epstein, Lanza and Skinner published a paper in the journal Science in which they argued that pigeons also pass the mirror test. A pigeon was trained to look in a mirror to find a response key behind it which it then turned to peck—food was the consequence of a correct choice (i.e., the pigeon learned to use a mirror to find critical elements of its environment). Next, the bird was trained to peck at dots placed on its feathers; food was, again, the consequence of touching the dot. This was done without a mirror. Then a small bib was placed on the pigeon—enough to cover a dot placed on its lower belly. A control period without the mirror yielded no pecking at the dot. But when the mirror was shown, the pigeon became active, looked into it and then tried to peck on the dot under the bib.
Untrained pigeons have never been able to pass the mirror test. However, pigeons do not normally have access to mirrors and do not have the necessary experiences to use them. Giving a pigeon this experience in no way guaranteed it would pass the mirror test, since the pigeon never pecked dots on its own body in the presence of the mirror (until the final test).
Despite this, pigeons are not classified as being able to recognize their reflection, because those that did were trained to do so and the animal must be able to do this without human assistance: it must also be shown that the birds are able to do this in the wild with no experience, just on their own intelligence. But even when an animal is trained to do this, it is still unknown if they are self-aware, or are just repeating the same movements and commands that they were taught so that they may receive a treat as a reward after they have correctly completed their task.
Some studies have suggested that birds—separated from mammals by over 300 million years of independent evolution—have developed brains capable of primate-like consciousness through a process of convergent evolution. Although avian brains are structurally very different from the brains of cognitively-advanced mammals, each has the neural circuitry associated with higher-level consciousness, according to a 2006 analysis of the neuroanatomy of consciousness in birds and mammals. The study acknowledges that similar neural circuitry does not by itself prove consciousness, but notes its consistency with suggestive evidence from experiments on birds’ working and episodic memory, sense of object permanence, and theory of mind .
Many birds have been shown capable of using tools. The definition of a tool has been debated. One proposed definition of tool use has been defined by T. B. Jones and A. C. Kamil in 1973 as
the use of physical objects other than the animal's own body or appendages as a means to extend the physical influence realized by the animal
By this definition, a bearded vulture (lammergeier) dropping a bone on a rock would not be using a tool since the rock cannot be seen as an extension of the body. However the use of a rock manipulated using the beak to crack an ostrich egg would qualify the Egyptian vulture as a tool user. Many other species, including parrots, corvids and a range of passerines, have been noted as tool users.
New Caledonian crows have been observed in the wild to use sticks with their beaks to extract insects from logs. While young birds in the wild normally learn this technique from elders, a laboratory crow named "Betty" improvised a hooked tool from a wire with no prior experience. The woodpecker finch from the Galapagos Islands also uses simple stick tools to assist it in obtaining food. In captivity, a young Española cactus finch learned to imitate this behavior by watching a woodpecker finch in an adjacent cage.
Crows in urban Japan and the United States have innovated a technique to crack hard-shelled nuts by dropping them onto crosswalks and letting them be run over and cracked by cars. They then retrieve the cracked nuts when the cars are stopped at the red light. Macaws have been shown to utilize rope to fetch items that would normally be difficult to reach. Striated herons (Butorides striatus) use bait to catch fish.
Using rewards to reinforce responses is often used in laboratories to test intelligence. However, the ability of animals to learn by observation and imitation is considered more significant. Crows have been noted for their ability to learn from each other.
At the beginning of the 20th century, scientists argued that the birds had hyper-developed basal ganglia, with tiny mammalian-like telencephalon structures. Modern studies have refuted this view. The basal ganglia only occupy a small part of the avian brain. Instead, it seems that birds use a different part of their brain, the medio-rostral neostriatum/hyperstriatum ventrale (see also nidopallium), as the seat of their intelligence, and the brain-to-body size ratio of psittacines (parrots) and corvines (birds of the crow family) is actually comparable to that of higher primates.
Studies with captive birds have given insight into which birds are the most intelligent. While parrots have the distinction of being able to mimic human speech, studies with the grey parrot have shown that some are able to associate words with their meanings and form simple sentences (see Alex). Parrots and the corvid family of crows, ravens, and jays are considered the most intelligent of birds. Not surprisingly, research has shown that these species tend to have the largest HVCs. Dr. Harvey J. Karten, a neuroscientist at UCSD who has studied the physiology of birds, has discovered that the lower parts of avian brains are similar to those of humans.
Social life has been considered to be a driving force for the evolution of intelligence. Many birds have social organizations, and loose aggregations are common. Many corvid species separate into small family groups (or "clans") for activities such as nesting and territorial defense. The birds then congregate in massive flocks made up of several different species for migratory purposes. Some birds use teamwork while hunting. Predatory birds hunting in pairs have been observed using a "bait and switch" technique, whereby one bird will distract the prey while the other swoops in for the kill.
Social behavior requires individual identification, and most birds appear to be capable of recognizing mates, siblings and young. Other behaviors such as play and cooperative breeding are also considered indicators of intelligence.
Crows appear to be able to remember who observed them caching food. They also steal food cached by others.
In some fairy-wrens such as the superb and red-backed, males pick flower petals in colors contrasting with their bright nuptial plumage and present them to others of their species that will acknowledge, inspect and sometimes manipulate the petals. This function seems not linked to sexual or aggressive activity in the short and medium term thereafter, though its function is apparently not aggressive and quite possibly sexual.
Birds communicate with their flockmates through song, calls, and body language. Studies have shown that the intricate territorial songs of some birds must be learned at an early age, and that the memory of the song will serve the bird for the rest of its life. Some bird species are able to communicate in several regional varieties of their songs. For example, the New Zealand saddleback will learn the different song "dialects" of clans of its own species, much as human beings might acquire diverse regional dialects. When a territory-owning male of the species dies, a young male will immediately take his place, singing to prospective mates in the dialect appropriate to the territory he is in. Similarly, around 300 tui songs have been recorded. The greater the competition in the area, it has been suggested, the more likely the birds are to actually create or make their song more complex.
Recent studies indicate that some birds may have an ability to memorize "syntactic" patterns of sounds, and that they can be taught to reject the ones determined to be incorrect by the human trainers. These experiments were carried out by combining whistles, rattles, warbles, and high-frequency motifs.
Evidence that birds can form abstract concepts such as same v. different has been provided by Alex, the grey parrot. Alex was trained by animal psychologist Irene Pepperberg to vocally label more than 100 objects of different colors and shapes and which are made from different materials. Alex could also request or refuse these objects ('I want X') and quantify numbers of them.
Macaws as well as carrion crows have been demonstrated to fully comprehend the concept of object permanence at a young age. Macaws will even refute the "A-not-B error". If they are shown an item, especially one with whose purpose they are familiar—they will search logically for where it could be feasibly placed. One test for was done as follows: A macaw was shown an item; the item was then hidden behind the back of the trainer and placed into a container. The container it was placed in without the macaw seeing, along with another container and multiple objects, were spread upon a table simultaneously. The specific container that the item was stored in out of the macaws' sight was one that the macaw had never observed before. The macaw searched this some, then another container, then returning to open the correct container to demonstrate knowledge of and the ability to search for the item.
A study on the little green bee-eater suggests that these birds may be able to see from the point of view of a predator. The brown-necked raven has been observed hunting lizards in complex cooperation with other ravens, demonstrating an apparent understanding of prey behavior. The California scrub jay hides caches of food and will later re-hide food if it was watched by another bird the first time, but only if the bird hiding the food has itself stolen food before from a cache. A male Eurasian jay takes into account which food his bonded partner prefers to eat when feeding her during courtship feeding rituals. Such an ability to see from the point of view of another individual and to attribute motivations and desires had previously been attributed only to the great apes and elephants.
Bird anatomy, or the physiological structure of birds' bodies, shows many unique adaptations, mostly aiding flight. Birds have a light skeletal system and light but powerful musculature which, along with circulatory and respiratory systems capable of very high metabolic rates and oxygen supply, permit the bird to fly. The development of a beak has led to evolution of a specially adapted digestive system. These anatomical specializations have earned birds their own class in the vertebrate phylum.Cetacean intelligence
Cetacean intelligence is the cognitive ability of the order Cetacea of mammals. This order includes whales, porpoises, and dolphins.Dinosaur intelligence
Dinosaur intelligence has been a point of contention for paleontologists. Non-avian dinosaurs were once regarded as being unintelligent animals but have largely been appraised more generously since the dinosaur renaissance. This new found optimism for dinosaur intelligence has led to highly exaggerated portrayals in pop-cultural works like Jurassic Park. Paleontologists now regard dinosaurs as being very intelligent for reptiles, but generally not as smart as their avian descendants. Some have speculated that if the Cretaceous–Paleogene extinction event had not occurred, the more intelligent forms of small theropods might have eventually evolved human-like levels of intelligence. Popular misconceptions of dinosaur neurology include the concept of a second brain in the pelvis of stegosaurs and sauropods.Encephalization quotient
Encephalization quotient (EQ), encephalization level or just encephalization is a relative brain size measure that is defined as the ratio between observed to predicted brain mass for an animal of a given size, based on nonlinear regression on a range of reference species.. It has been used as a proxy for intelligence and thus as a possible way of comparing the intelligences of different species.
For this purpose it is a more refined measurement than the raw brain-to-body mass ratio, as it takes into account allometric effects. The relationship, expressed as a formula, has been developed for mammals, and may not yield relevant results when applied outside this group.Evolution of cognition
Evolution of cognition is the idea that life on earth has gone from organisms with little to no cognitive function to a greatly varying display of cognitive function that we see in organisms today. Animal cognition is largely studied by observing behavior, which makes studying extinct species difficult. The definition of cognition varies by discipline; psychologists tend define cognition by human behaviors, while ethologists have widely varying definitions. Ethological definitions of cognition range from only considering cognition in animals to be behaviors exhibited in humans, while others consider anything action involving a nervous system to be cognitive.Irene Pepperberg
Irene Maxine Pepperberg (born April 1, 1949 in Brooklyn, New York) is a scientist noted for her studies in animal cognition, particularly in relation to parrots. She is an adjunct professor of psychology at Brandeis University and a lecturer at Harvard University. Pepperberg also serves on the Advisory Council of METI (Messaging Extraterrestrial Intelligence). She is well known for her comparative studies into the cognitive fundamentals of language and communication, and was one of the first to work on language learning in animals other than human species (exemplified by the Washoe project), by extension to a bird species. Pepperberg is also active in wildlife conservation, especially in relation to parrots.Jimmy the raven
Jimmy the raven (often credited as Jimmy the crow) was a raven who appeared in more than 1,000 feature films from the 1930s through the 1950s. He first appeared in You Can't Take It with You in 1938, after which director Frank Capra cast the bird in every subsequent movie he made. Among his roles were Uncle Billy's pet, seen in the Building & Loan in It's a Wonderful Life, and the crow that landed on the Scarecrow in The Wizard of Oz.Jimmy belonged to Hollywood animal trainer Curly Twiford, who found the bird in a nest in the Mojave Desert in 1934. Twiford trained Jimmy to do an assortment of tricks, such as typing, opening letters, and even riding a tiny motorcycle: things that would make him appealing to use in films. Jimmy could understand several hundred words, though only around 50 were what Twiford called "useful". It took Jimmy a week to learn a new useful word—two weeks if it had 2 syllables. Twiford said that Jimmy could perform any task that an 8-year-old child could (see bird intelligence).His human co-stars were complimentary of the bird. "When they call Jimmy, we both answer," remarked Jimmy Stewart on the set of It's a Wonderful Life, noting that the raven "is the smartest actor on the set" requiring fewer re-takes than his human counterparts.As he became more popular with the studio, Metro-Goldwyn-Mayer had him insured for $10,000. Lloyd's of London wrote a policy to cover Jimmy's $500 a week fee as well as Curly Twiford's $200 handler fee, in the event Jimmy forgot any of the words he would need on the set. Twiford credited these fees with keeping him solvent during World War II. At one point, Jimmy had 21 stand-ins, 15 of which were female, who would fill in for him when the scene did not require any tricks or movement.Jimmy received a Red Cross gold medal in acknowledgement of 200 hours spent entertaining veterans after the war, and his footprints were enshrined in cement at a large Los Angeles pet store, alongside Lassie and other Hollywood animal stars.His last credited film was 3 Ring Circus in 1954, after which little is known about him. Though Curly Twiford said Jimmy would "probably live to be 150" years old, which the papers re-printed, in reality ravens seldom live more than 30 years in captivity. Twiford died in 1956 at the age of 60.Li River
The Li River or Li Jiang (Chinese: 漓江; pinyin: Lí Jiāng) is a river in Guangxi Zhuang Autonomous Region, China. It flows 83 kilometres (52 mi) from Guilin to Yangshuo, where the karst mountains and river sights highlight the famous Li River cruise.List of programs broadcast by Showtime
Showtime is an American premium cable and satellite television network. Showtime's programming primarily includes theatrically released motion pictures and original television series, along with boxing and mixed martial arts matches, occasional stand-up comedy specials and made-for-TV movies.Ornithology
Ornithology is a branch of zoology that concerns the study of birds. Several aspects of ornithology differ from related disciplines, due partly to the high visibility and the aesthetic appeal of birds.The science of ornithology has a long history and studies on birds have helped develop several key concepts in evolution, behaviour and ecology such as the definition of species, the process of speciation, instinct, learning, ecological niches, guilds, island biogeography, phylogeography, and conservation. While early ornithology was principally concerned with descriptions and distributions of species, ornithologists today seek answers to very specific questions, often using birds as models to test hypotheses or predictions based on theories. Most modern biological theories apply across taxonomic groups, and the number of professional scientists who identify themselves as "ornithologists" has therefore declined. A wide range of tools and techniques is used in ornithology, both inside the laboratory and out in the field, and innovations are constantly made.Pigeon intelligence
Pigeons have featured in numerous experiments in comparative psychology, including experiments concerned with animal cognition, and as a result there is considerable knowledge of pigeon intelligence.
Available data show, for example, that:
Pigeons have the capacity to share attention between different dimensions of a stimulus, but (like humans and other animals) their performance with multiple dimensions is worse than with a single stimulus dimension.
Pigeons can be taught relatively complex actions and response sequences, and can learn to make responses in different sequences.
Pigeons readily learn to respond in the presence of one simple stimulus and withhold responding in the presence of a different stimulus, or to make different responses in the presence of different stimuli.
Pigeons can discriminate between other individual pigeons, and can use the behaviour of another individual as a cue to tell them what response to make.
Pigeons readily learn to make discriminative responses to different categories of stimuli, defined either by arbitrary rules (e.g. green triangles) or by human concepts (e.g. pictures of human beings).
Pigeons do less well with categories defined by abstract logical relationships, e.g. "symmetrical" or "same", though some experimenters have successfully trained pigeons to discriminate such categories.
Pigeons seem to require more information than humans for constructing a three-dimensional image from a plane representation.
Pigeons seem to have difficulty in dealing with problems involving classes of classes. Thus they do not do very well with the isolation of a relationship among variables, as against a representation of a set of exemplars.
Pigeons can remember large numbers of individual images for a long time, e.g. hundreds of images for periods of several years.All these are capacities that are likely to be found in most mammal and bird species. In addition pigeons have unusual, perhaps unique, abilities to learn routes back to their home from long distances. This homing behaviour is different from that of birds that learn migration routes, which usually occurs over a fixed route at fixed times of the year, whereas homing is more flexible; however similar mechanisms may be involved.
Pigeons showed mirror-related behaviours during the mirror test.Snowball (cockatoo)
Snowball (hatched c. 1996) is a male Eleonora cockatoo, noted as being the first non-human animal conclusively demonstrated to be capable of beat induction: perceiving music and synchronizing his body movements to the beat (i.e. dancing).The Crow and the Pitcher
The Crow and the Pitcher is one of Aesop's Fables, numbered 390 in the Perry Index. It relates ancient observation of corvid behaviour that recent scientific studies have confirmed is goal-directed and indicative of causal knowledge rather than simply being due to instrumental conditioning.The Genius of Birds
The Genius of Birds is a 2016 book by nature writer Jennifer Ackerman.Tool use by animals
Tool use by animals is a phenomenon in which an animal uses any kind of tool in order to achieve a goal such as acquiring food and water, grooming, defense, recreation or construction. Originally thought to be a skill possessed only by humans, some tool use requires a sophisticated level of cognition. There is considerable discussion about the definition of what constitutes a tool and therefore which behaviours can be considered true examples of tool use. A wide range of animals, including mammals, birds, fish, cephalopods, and insects, are considered to use tools.
Primates are well known for using tools for hunting or gathering food and water, cover for rain, and self-defence. Chimpanzees have been the object of study, most famously by Jane Goodall, since these animals are more-often kept in captivity than other primates and are closely related to humans. Tool-use in other primates are lesser-known as many of them are mainly observed in the wild. Many famous researchers, such as Charles Darwin in his book The Descent of Man, mentioned tool-use in monkeys (such as baboons). Both wild and captive elephants are known to create tools using their trunk and feet, mainly for swatting flies, scratching, plugging water-holes (so the water doesn't evaporate), and reaching food that is out of reach. A group of dolphins in Shark Bay use sponges to protect their beak while foraging. Sea otters will dislodge food from rocks (such as abalone) and break open shellfish. Carnivores (of the order Carnivora) can use tools to trap prey or break open the shells of prey, as well as for scratching.
Corvids (crows, ravens and rooks) are well known for their large brains (among birds) and subsequent tool use. They mainly manufacture probes out of twigs and wood (and sometimes metal wire) to catch or impale larvae. Crows are among the only animals that create their own tools. Tool use in other birds is best exemplified in nest intricacy. Warblers manufacture 'pouches' to make their nests in. Some birds, such as weaver birds build complex nests. Finches and woodpeckers may insert twigs into trees in order to catch or impale larvae. Parrots may use tools to wedge nuts so that they may crack it open (using a tool) without launching it away. Some birds take advantage of human activity, such as some species of gulls which drop shellfish in front of cars to crack them open.
Several species of fish use tools to crack open shellfish, extract food that is out of reach, cleaning an area (for nesting), and hunting. Octopuses gather coconut shells and create a shelter. They may also construct a fence using rocks.
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