Bird intelligence deals with the definition of intelligence and its measurement as it applies to birds. Traditionally, birds have been considered inferior in intelligence to mammals, and derogatory terms such as bird brains have been used colloquially in some cultures. For other uses, see Intelligence (disambiguation). ... For other uses, see Bird (disambiguation). ... Subclasses & Infraclasses Subclass †Allotheria* Subclass Prototheria Subclass Theria Infraclass †Trituberculata Infraclass Metatheria Infraclass Eutheria Mammals (class Mammalia) are warm-blooded, vertebrate animals characterized by the production of milk in female mammary glands and by the presence of: hair, three middle ear bones used in hearing, and a neocortex region in...

It is everywhere recognized that birds possess highly complex instinctive endowments and that their intelligence is very limited.

—Herrick, 1924^[1]

Such perceptions are no longer considered valid. The difficulty of defining or measuring intelligence makes the subject difficult for scientific study. Anatomically, birds have a relatively large brain compared to head size. The visual and auditory senses are well developed in most species, while tactile and olfactory senses are well developed only in a few groups. Locomotion is achieved through flight and use of the legs in most species. The beak and feet are used to manipulate food and other objects. Birds can 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.

Studies of bird intelligence

Cormorants used by fishermen in Southeast Asia may be able to count

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 such as the corvids and psittacines have been shown to live social lives, have long developmental periods and large forebrains, and these may be expected to have greater cognitive abilities.^[2] Image File history File links Size of this preview: 404 × 599 pixels Full resolution (575 × 853 pixel, file size: 167 KB, MIME type: image/jpeg) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Bird Bird intelligence ... Image File history File links Size of this preview: 404 × 599 pixels Full resolution (575 × 853 pixel, file size: 167 KB, MIME type: image/jpeg) File links The following pages on the English Wikipedia link to this file (pages on other projects are not listed): Bird Bird intelligence ...

Counting

Counting has been considered an ability that shows intelligence. Early bird photographers used hides to take pictures of birds at nest. They noticed that some species are alarmed by human presence and wait for the human to leave the hide before approaching. Some photographers tried a technique to fool the birds by having two people enter the hide and having only one leave it. Many birds failed to see the trick and returned to their nests assuming that the human had left. However, crows were found to be able to keep count and a figure of 7 was found to be the limit of their counting ability.^{[citation needed]}Cormorants used by Chinese fishermen that were given every eighth fish as a reward were found to be able to keep count up to eight. For other uses, see Cormorant (disambiguation). ...

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.

—Hoh, E. H.^[3]

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.

Associative learning

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.^[4]

Spatial and temporal abilities

A flock of swans migrating

A common test of intelligence is the detour test. Here 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. Domestic fowl fail on this test.^[5] Many corvids were found to readily solve the problem. Image File history File links Metadata No higher resolution available. ... Genera many, see article text Corvidae is a family of oscine passerine birds that contains the crows, ravens, rooks, jackdaws, jays, magpies, treepies and nutcrackers (Clayton and Emery 2005, [1]). Collectively its members are called corvids and there are over 120 species. ...

Large fruit-eating birds in tropical forests depend on trees which 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 caching behaviour have also shown the ability to recollect the locations of food caches.^[6][7] Nectarivorous birds such as hummingbirds also optimize their foraging by keeping track of the locations of good and bad flowers.^[8] Studies of Western Scrub Jays (Aphelocoma californica) also suggests that birds may be able to plan for the future. They cache food according to future needs and risk of not being able to find the food on subsequent days.^[9]

Many birds follow strict time schedules in their activities. These are often dependent upon environmental cues. Birds also are sensitive to daylight 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.

Tool use

Many birds have been shown capable of using tools. The definition of a tool has been debated. Tool use has been defined 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

—Jones and Kamil, 1973^[10]

By this definition, an Egyptian vulture 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.^[2] Video of parrot demonstrating tool use.

This New Caledonian postage stamp depicts a crow using a simple stick tool.

New Caledonian Crows have been observed in the wild to use stick tools 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.^[11] The Woodpecker Finch from the Galapagos Islands also uses simple stick tools to assist it in obtaining food. In captivity, a young Cactus Finch learned to imitate this behaviour by watching a woodpecker finch in an adjacent cage. Crows in urban Japan 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 retrieved the cracked nuts when the cars were stopped at the red light. Striated Herons (Butorides striatus) use bait to catch fish. Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Binomial name Corvus moneduloides Lesson, 1830 The New Caledonian Crow (Corvus moneduloides) is a moderately sized crow (40 cm in length) similar in size to the House Crow but less slender looking. ... The Woodpecker Finch was first seen by Charles Darwin on the Galapagos Islands. ... A cage designed for medium-large parrots, with a playtop. ... Binomial name Butorides striatus (Linnaeus, 1758) The Striated Heron (or Mangrove Heron or Little Heron), Butorides striatus, is a small heron. ...

Observational learning

Learning 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.^[12]

Brain anatomy

At the beginning of the 20th century, scientists argued that the birds had hyper-developed basal ganglia, with a little mammalian-like telencephalon structures.^[13]. Modern studies have refuted this view ^[14] Basal ganglia only occupies 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, as the seat of their intelligence, and the brain-to-body size ratio of psittacines and corvines is actually comparable to that of higher primates.^[15][16]

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 African Grey Parrot have shown that some are able to associate words with their meanings and form simple sentences (see Alex). Along with parrots, the crows, ravens, and jays (family Corvidae) are perhaps the most intelligent of birds. Not surprisingly, research has shown that these species tend to have the largest hyperstriata. 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. Systematics (but see below) Family Cacatuidae (cockatoos) Family Psittacidae (true parrots) Subfamily Loriinae (lories and lorikeets) Subfamily Psittacinae (typical parrots and allies) Tribe Arini (American psittacines) Tribe Cyclopsitticini (fig-parrots) Tribe Micropsittini (pygmy-parrots) Tribe Nestorini (kakas and Kea) Tribe Platycercini (broad-tailed parrots) Tribe Psittrichadini (Pesquets Parrot) Tribe... Binomial name Psittacus erithacus Linnaeus, 1758 Subspecies The African Grey Parrot is a medium-sized parrot of the genus Psittacus, native to Africa and is considered one of the most intelligent birds. ... Alex is an African grey parrot whose use of language has been studied intensively for over 30 years by animal psychologist Irene Pepperberg, initially at the University of Arizona and currently at Brandeis University. ... Genera many, see article text Corvidae is a family of oscine passerine birds that contains the crows, ravens, rooks, jackdaws, jays, magpies, treepies and nutcrackers (Clayton and Emery 2005, [1]). Collectively its members are called corvids and there are over 120 species. ... The University of California, San Diego (popularly known as UCSD, or sometimes UC San Diego) is a public, coeducational research university located in La Jolla, a seaside resort community of San Diego, California. ...

Social behaviour

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 behaviour requires individual identification, and most birds appear to be capable of recognizing mates, siblings and young. Other behaviours such as play and cooperative breeding are also considered indicators of intelligence.

When crows are caching food, they appear to be sensitive to note who is watching them hide the food. They also steal food cached by others.^[17]

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 conspecifics 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. ^[18] Genera Malurus Sipodotus Clytomyias Stipiturus Amytornis The Maluridae are a family of small, insectivouous passerine birds endemic to Australia and New Guinea. ... Binomial name Malurus cyaneus Latham, 1783 The Superb Fairy-wren (Malurus cyaneus) is the best-known of all fairy-wrens, and in south-eastern Australia is frequently known simply as the blue wren. ... Binomial name (Latham, 1801) The Red-backed Fairy-wren (Malurus melanocephalus) is a species of bird in the Maluridae family. ... For the petals of chakras, see Petal (chakra). ... Nubian wedding with some international modern touches, near Aswan, Egypt Preparing for the photographs, at a wedding in Thornbury Castle, England A traditional Japanese wedding ceremony A wedding is a civil or religious ceremony which celebrates the beginning of a marriage. ...

Language

Main article: Talking birds

While birds have no form of spoken language, they do 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 a variety of dialects. For example, the New Zealand saddleback will learn the different song "dialects" of clans of its own species, much as human beings might learn 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. ^{[citation needed]} Talking birds are birds who can imitate human speech. ...

Recent studies indicate that some birds may have an ability to understand grammatical structures.

Conceptual abilities

Evidence that birds can form abstract concepts such as same–different has been proven by Alex, the African grey parrot. Alex was trained to vocally label more than 100 objects of different colours and shapes and which are made from different materials. Alex can also request or refuse these objects ('I want X') and quantify numbers of them.^[19]

Medication

Macaws in the rain forest of Peru have been noted to eat fruits that are poisonous during certain seasons. They later feed on clay at avian clay licks. These appear to bind the toxins in the food and prevent sickness in the birds. Very large aggregations of birds at these clay sites have been noted.^[20] The Gay Head cliffs in Marthas Vineyard are made almost entirely of clay. ...

Other abilities

A study on the Little Green Bee-eater suggested that these birds may be able to see from the point of view of a predator. Such an ability to see from the point of view of another individual has been attributed only to the Great Apes. Such abilities form the basis for empathy.^[21] Binomial name Merops orientalis Latham, 1802 The Little Green Bee-eater, Merops orientalis, is a near passerine bird in the bee-eater family Meropidae. ...

References

Emu, subtitled Austral Ornithology (ISSN 0158-4197), is the peer-reviewed scientific journal of the Royal Australasian Ornithologists Union (RAOU). ...

See also

• Avian Brain Nomenclature Consortium
• Animal intelligence
• Pigeon intelligence

The Avian Brain Nomenclature Consortium is a group of neuroscientists working on standardizing and updating the scientific language used to describe parts of bird brains. ... The term Animal intelligence is currently used in three distinct but overlapping ways: as a synonym for animal cognition, to pose the question “are animals intelligent?”, or to denote a discussion of relative levels of intelligence in different animal species. ... Pigeons have featured in numerous experiments in comparative psychology, including experiments concerned with animal cognition, and as a result we have considerable knowledge of pigeon intelligence. ...

External links

• An overview of the brain at the Life of Birds website
• The anatomy of a bird brain
• Crow Makes Tool by Bending Wire to Snag Food
• Tool using in birds
• Video of parrot demonstrating tool use