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Proof of animal intelligence
Bet you didn't know how smart these animals are. You may change your view of them after you read this.
Dogs can detect if someone has cancer
Dogs can detect if someone has cancer just by sniffing the person's breath, a new study shows.
Dogs can identify chemical traces in the range of parts per trillion. Previous studies have confirmed the ability of trained dogs to detect skin-cancer melanomas by sniffing skin lesions.
Also, some researchers hope to prove dogs can detect prostate cancer by smelling patients' urine.
Lung- and breast-cancer patients are known to exhale patterns of biochemical markers in their breath.
"Cancer cells emit different metabolic waste products than normal cells," Broffman said. "The differences between these metabolic products are so great that they can be detected by a dog's keen sense of smell, even in the early stages of disease."
History of the guide dog
The first special relationship between a dog and a blind person is lost in the mists of time, but perhaps the earliest known example is depicted in a first-century AD mural in the buried ruins of Roman Heculaneum. From the Middle Ages, too, a wooden plaque survives showing a dog leading a blind man with a leash.
However, the first systematic attempt to train dogs to aid blind people came around 1780 at ‘Les Quinze-Vingts’ hospital for the blind in Paris. Shortly afterwards, in 1788, Josef Riesinger, a blind sieve-maker from Vienna, trained a spitz so well that people often doubted that he was blind.
The modern guide dog story, however, begins during the First World War, when thousands of soldiers were returning from the Front blinded, often by poison gas. A German doctor, Dr Gerhard Stalling, had the idea of training dogs en masse to help those affected. While walking with a patient one day through the hospital grounds, he was called away urgently and left his dog with the patient as company. When he returned, he got the distinct impression from the way the dog was behaving that it was looking after the blind patient.
— DOGS —
Stanley Coren, author of more than a half-dozen popular books on dogs and dog behavior, has reviewed numerous studies to conclude that dogs have the ability to solve complex problems and are more like humans and other higher primates than previously thought.
"We all want insight into how our furry companions think, and we want to understand the silly, quirky and apparently irrational behaviors [that] Lassie or Rover demonstrate," Coren said in an interview. "Their stunning flashes of brilliance and creativity are reminders that they may not be Einsteins but are sure closer to humans than we thought."
According to several behavioral measures, Coren says dogs' mental abilities are close to a human child age 2 to 2.5 years.
The intelligence of various types of dogs does differ and the dog's breed determines some of these differences, Coren says. "There are three types of dog intelligence: instinctive (what the dog is bred to do), adaptive (how well the dog learns from its environment to solve problems) and working and obedience (the equivalent of 'school learning')."
Data from 208 dog obedience judges from the United States and Canada showed the differences in working and obedience intelligence of dog breeds, according to Coren. "Border collies are number one; poodles are second, followed by German shepherds. Fourth on the list is golden retrievers; fifth, dobermans; sixth, Shetland sheepdogs; and finally, Labrador retrievers," said Coren.
As for language, the average dog can learn 165 words, including signals, and the "super dogs" (those in the top 20 percent of dog intelligence) can learn 250 words, Coren says. "The upper limit of dogs' ability to learn language is partly based on a study of a border collie named Rico who showed knowledge of 200 spoken words and demonstrated 'fast-track learning,' which scientists believed to be found only in humans and language learning apes," Coren said.
Dogs can also count up to four or five, said Coren. And they have a basic understanding of arithmetic and will notice errors in simple computations, such as 1+1=1 or 1+1=3.
Four studies he examined looked how dogs solve spatial problems by modeling human or other dogs' behavior using a barrier type problem. Through observation, Coren said, dogs can learn the location of valued items (treats), better routes in the environment (the fastest way to a favorite chair), how to operate mechanisms (such as latches and simple machines) and the meaning of words and symbolic concepts (sometimes by simply listening to people speak and watching their actions).
During play, dogs are capable of deliberately trying to deceive other dogs and people in order to get rewards, said Coren. "And they are nearly as successful in deceiving humans as humans are in deceiving dogs."
Meet Sergeant Stubby
Stubby was just another stray dog before he found his way into an area near Yale University where the 102nd infantry, Yankee Division was training for World War I. Private J. Robert Conroy found the puppy there in 1917 and named him Stubby on account of his short tail. Although animals were not allowed in the regiment, Stubby was allowed to stick around because he was smart and boosted morale. He learned the bugle calls, the drills and even a modified salute where he put his right paw on his right eyebrow. Later he proved his usefulness at war. Conroy smuggled the pooch aboard a ship to France, and when he was discovered by Conroy's commanding officer, Stubby won him over with an adorable salute.
He was allowed to join the soldiers on the front lines, where he was once injured during a gas strike. Having developed a sensitivity to the smell of gas, he was able to save the soldiers as they slept through another gas attack. He even thwarted a German soldier's attempts to map out the layout of Allied trenches by biting him on the leg and subduing him until U.S. soldiers arrived. By the end of the war, Stubby had served in 17 battles and had developed a knack for locating his wounded comrades. The dog became a lifetime member of the American Legion and later became Georgetown University's mascot when Conroy went to study law there. In 1921 the pooch was awarded a gold hero dog's medal that was commissioned by the Humane Education Society. He lived until 1926.
Lola, the cat who walks on her front legs
Psychic Connections with Your Cat
Animal psychics nationwide, and many of the people they have helped to make a connection with their pets, says it's no coincidence. By using psychic or telepathic animal communication, you can talk to cats through inner sight, sound and feelings, they claim. They're not talking about hearing your cat meow or reading his body language. It's about transmitting an unseen message on a wavelength we share with our animals--a telepathic channel we can all find.
— CATS —
How Smart Are Cats?
As early as the 1920s, researchers found that cats can learn complex tasks, especially if the reward is food. And in highly structured tests of learning ability, cats often outperformed dogs in the ability to master conceptual problems. In the 1950s, animal behaviorist J. M. Warren at Pennsylvania State University at University Park described the cat's ability to master "oddity learning" in which the animal is shown three objects and is rewarded for selecting the one that is most unlike the other two. In the test, cats learned to paw a square block rather than two round blocks presented at the same time, because food was hidden beneath the square block. In similar tests, the cat chose the different object when presented with one round block and two squares.
Such tests require the ability to understand concepts, in this case, that of similarity and dissimilarity. Researchers have found that some cats do as well with this type of conceptual learning as monkeys. And, aside from monkeys and other primates, cats are among the most adept at learning by observing the successes and failures of other animals attempting to complete tasks to obtain a reward.
Learning from Experience and Practice
Cats may appear unable to learn, but in many cases, it’s just that the subject matter doesn’t particularly interest them. Cats learn from experience when they find the information relevant, which is why they can develop phobias quite easily. After a single traumatic experience, such as being roughly handled by a certain type of person (i.e., a child), the cat may subsequently avoid that category of person completely.
Cats are also good at remembering useful information (such as noises they have made that achieved the desired response from their owners) and they can recognize the people and animals they have interacted with. They can also learn their owners’ schedules. As a result, some cats will act as alarm clocks, attempting to wake their owners if they sleep past the usual time. In addition, many cats have the uncanny ability of knowing when their owners are about to arrive home, even when they aren’t returning at the usual time. It’s been theorized that this ability stems from a cat’s superior hearing and the capacity to recognize the sound of his owner’s footsteps from far away.
Many cat owners have noticed the extraordinary lengths some pets will go to attain a desired goal, and the way that they will try multiple strategies, rejecting an approach that proves ineffective and trying something new, rather than simply doing the same thing over and over again. Cats have also been known to problem solve by observing humans. For example, a cat may watch a person open a door by turning the knob and later jump up on a nearby object and attempt to turn the doorknob with his paws. Such attempts are inevitably thwarted by a lack of opposable thumbs, but the fact that a cat would try such a strategy indicates some degree of intelligence.
Cats have phenomenal memories for directions that often enable them to find their way home after travelling long distances. This superior navigation ability is believed to derive from two things: using the angle of the sun for navigation (which can be done even on cloudy days because the cat uses polarized light for wayfinding) and being sensitive to the Earth’s magnetic fields. This latter hypothesis was borne out when it was found that attaching a magnet to a cat will disrupt his navigational skills.
Do cats have a 6th sense?
Some scientists, including Dr Rupert Sheldrake of England’s world-renowned and respected Cambridge University, believe that cats are clairvoyant and telepathic, citing even everyday examples such as cats apparently sensing when a loved one is on the phone before it rings (not to mention their unerring homing instinct) as proof.
As for ‘predicting’ natural disasters, scientists believe animals’ acute sense of hearing give them early warning, and also add the possibility that they may be able to detect subtle vibrations or even changes in the air or in electromagnetic fields.
The iPad game you play against your cat
Friskies created the first interspecies game: You vs. Cat
The game is simple enough: At one end of the screen the human slings a piece of animated cat food onto the playing board.
The goal? Get the item across the screen into a goal box before you cat stops it by putting its paw on the item.
It’s sort of a 21st century air hockey table for you and your favorite feline friend.
There’s even an automatic scoreboard at YouVsCat.com, where Friskies has posted the You vs. Cat World-Wide Leaderboard to track gameplay on all iPads that are connected to the internet.
Thanks to his guide cat, blind dog can go for walks again
After going blind from cataracts, 8-year-old dog Terfel struggled to get around on his own. He spent most of his time lazing around in his basket in his owner's North Wales, UK home.
Then his owner, Judy Godfrey-Brown, welcomed a stray cat into her home.
The cat, dubbed Pwditat, walked up to the blind dog and led him into the garden. Ever since, the cat has been Terfel's trusty guide, leading him everywhere.
VIDEO CLIP http://news.yahoo.com/video/trending-blind-dog-gets-seeing-000000278.html
Cat saves boy from dog attack
A heroic cat saved its young owner from a dog attack by hurling itself in between the canine and the four-year-old boy in Bakersfield, California.
Surveillance cameras caught the entire incident, which lasted less than a minute, on tape. The boy's father uploaded the footage on YouTube.
Four-year-old Jeremy can be seen riding his bicycle in a driveway, when a neighbor's dog sneaks up on him around the side of a white vehicle.
The dog, identified by local news station KERO as an eight-month-old Labrador and Chow mix, bites the boy on his left leg, pulling him from the bicycle onto the ground and dragging him for a short distance.
The family's cat, Tara, sprints into the frame and hurls itself at the dog, causing it to release its grip on the boy. The cat then chases it away.
The boy's mother, Erica Triantafilo, then runs to Jeremy and checks his wounds, his father, Roger Triantafilo, explains in the comments section of his YouTube video.
She leaves Jeremy and chases the dog to ensure it doesn't attack him again, he writes.
"She was bit by the dog as she tried to pin him in his yard," he says, adding the owners regained control of the pup.
Jeremy appears to have suffered bite wounds and required several stitches.
"Tara is my hero," he told KERO, which identified and spoke with the family.
VIDEO CLIP http://www.youtube.com/watch?v=Y6GQR3Ym5M8
Cormorant fishing is a traditional fishing method in which fishermen use trained cormorants to fish in rivers. Historically, cormorant fishing has taken place in Japan and China, as well as other places throughout the world.To control the birds, the fishermen tie a snare near the base of the bird's throat. This prevents the birds from swallowing larger fish, which are held in their throat, but the birds can swallow smaller fish. When a cormorant has caught a fish in its throat, the fisherman brings the bird back to the boat and has the bird spit the fish up. Though cormorant fishing once was a successful industry, its primary use today is to serve the tourism industry.
The key to their adaptable nature might be their intelligence -- as evidenced by their ability to accurately count beyond the number seven. Chinese cormorants on the Li River are allowed to keep every eighth fish they catch. Otherwise they "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."
*The pigeon can recognize all 26 letters of the English language.
*They can be taught relatively complex actions and response sequences, and can learn to make responses in different sequences.
*In scientific tests pigeons have been found to be able to differentiate between photographs and even between two different human beings in a photograph.
*A study conducted at Keio University in Japan demonstrated that pigeons could learn to distinguish between a Van Gogh and a Chagall paintings, based on multiple feature cues, such as color and pattern.
*Pigeons can remember large numbers of individual images for a long time, for example hundreds of images for periods of several years.
Life-saving Pigeons: The pigeon have far better eyesight than humans and even though they can see color in the same way that humans do, pigeons can also see ultra-violet - a part of the spectrum that humans cannot see. They can also learn relatively complex actions and response sequences and can be taught to make responses in different sequences. These sets of skills were utilized to save thousands of people lost at sea and during numerous rescue missions during times of war (World Wars I and II).
Navigation: Their most unique ability it to learn routes back to their home from long distances. This homing behavior differs from that of birds that migrate - which usually occurs over a fixed route at fixed times of the year. Homing, however, is more flexible, although similar mechanisms may be involved. Their homing ability has been used by humans for myriad purposes.
READ MORE about Homing Pigeons http://www.avianweb.com/messengerpigeons.html#rescue
— BIRDS —
Birds can be very resourceful - "Tool user," once a term used exclusively to define and distinguish mankind, is today also applied to birds. Wild birds have been observed to lay walnuts in the roadway so passing cars will crack them open. Captive cockatoos will clip off small sticks of wood with their beaks, and then use them to scratch various parts of their body.
Some birds can understand… and use… human language - At one time parrots where thought only to mimic speech. Hence, the term "parroting" was coined. Now, it appears this was in error. How would you react if, after you clean your bird's cage, he commented, "Looks good"? Alex, an African Grey parrot who was studied by Irene Pepperberg, did just that. Reportedly, Alex developed a 100-word vocabulary and could identify 50 different objects, recognize quantities up to six, distinguish seven colors and five shapes, and understand the difference between big and small, same and different, and over and under. Amazingly, Alex could put words together in new and meaningful phrases.
Birds may have exceptional memory - Wild birds can collect and bury thousands of seeds across hundreds of square miles, then retrieve over 90% or them. It is thought that these species have developed a specialized portion of their brain to accomplish the task. Alex, the African Grey, could tell you that corn is yellow, even if there is no corn in view.
Birds take enjoyment in intelligent play - Frolicking in a bird bath may, or may not, be simple instinct. But what about dropping marbles into a water bowl to study the splash? Turning somersaults? Or climbing a rope with their beak? Clearly, birds do many things just for the fun of it. Provided the right interactive toy, they will invest hours in play to satisfy their curiosity, and possibly earn intellectual reward.
Birds may display emotions - According to scientists, birds have the right equipment for emotion. They have a limbic system, a specialized portion of the brain, necessary for true emotional behavior. Other than birds, this system is found only in other higher vertebrates - man and other mammals. Bird owners have long felt they can tell whether their pets are happy or sad, fearful or content. Now research is underway to determine whether birds are aware of their own emotions, and the impact this awareness may have on their individual behavior.
— HORSES —
Horses have been shown to learn in five different ways which are all based on memory.
1. Habituation This is when a horse is repeatedly exposed to a certain stimulus. Eventually the horse will stop responding to the stimulation. An example of this is exposing a horse to traffic so the horse will no longer be frightened of cars. This can sometimes be a temporary form of learning because the animal’s more primitive instincts may emerge causing fear to emerge if the animal is stressed.
2. Associated Learning There are two types of associated learning. The first is the classical type which was first documented by Pavlov in the early 1900’s. Dealing with horses, a trainer could click his tongue when the horse was about to break into a canter and give positive reinforcement when the horse complies. The clicking of a rider’s tongue will now be the signal for a canter. The operant type is when a reward is associated with its own behavior. A trainer will present a horse with a choice, go right or left when pressure is applied to the left. When the horse chooses correctly, he is rewarded. The wrong choice means no reward. The horse will remember the right choice earns the reward.
3. Latent Learning This is the ability of the memory to store an experience unconsciously. This type of learning does not require any training. This type of learning is evident when horses automatically remember places, routes, and locations.
4. Imprinting This is when early perceptual experiences are marked into the horse’s brain. Trainers often take advantage of this type of learning with young foals, as young as 1 hour old. They will try to desensitize the animals to alarming sensations, sights and sounds.
5. Insight Learning This is when the horse is taught how to learn. It is based on the premise of stimulus-response-reinforcement. This is similar to the operant type of associated learning but the insight learning focuses more on emotional reinforcement. This type of learning will require a strong relationship between horse and trainer.
— CHIMPANZEES —
In the past few decades, scientific evidence on chimps and other nonhuman primates has poured in to support one basic fact: We have much more in common with the apes than most people care to believe. Often cited is the statistic that humans have 98.4% of the same DNA as chimps, humans having branched off from chimpanzees just six million years ago on the evolutionary tree. Research suggests that, like us, chimps are highly intelligent, cooperative and sometimes violent primates who nurture family bonds, adopt orphans, mourn the death of mothers, practice self-medication, struggle for power and wage war. And that only makes sense, because the chimp brain and the human brain both evolved from the same brain-that of our common ape ancestor. The mental processes inside these two brains have become specialized as they adapted to different social needs over six million years, but they still share the same underlying ancestral intelligence.
In the past year alone, numerous studies have highlighted our remarkable likeness not only to chimps, but to monkeys and apes of all kinds. A 1999 Columbia study conducted by psychologist Herbert Terrace, Ph.D., showed that rhesus monkeys have rudimentary arithmetic skills, and that they can think using symbols. The Yerkes Regional Primate Research Center released a study in April indicating that capuchin monkeys work together to gather food and then share the fruits of their labor; head researcher Frans de Waal, Ph.D., suggests that this kind of cooperation may be an essential element of human society. And a study published last May in the journal Nature by famed chimpanzee researchers Jane Goodall, Ph.D., and Andrew Whiten, Ph.D., shows that chimpanzees engage in more behaviors than are necessary for mere survival, and that these behaviors-which range from using rocks as hammers to crack nuts to not using tools at all--vary geographically, sound evidence that chimps might have region-specific cultures.
Certainly, humans and chimpanzees differ in intellectual ability. But what differs is their degree of intelligence, not the kind of mental processes they employ. There is no bold line separating human intelligence from chimp intelligence.
My careful observations of chimps, comparing their specific behaviors to those of humans, have shown me that our thoughts and actions overlap in many ways. These up-close-and-personal experiences have given me proof of their compassion, their cooperation, their empathy, their duplicity. The reason that chimps are the frequent subjects of scientific experiments is the very reason that testing land inferior treatment is wrong: More than just our biological cousins, they are also our psychological and emotional cousins.
— ORANGUTANS —
Imitation Imitation by one individual of actions of another individual(s) is probably the first indicator of intelligence of a certain species.
In case with orangutans, we don't need to go far for the proof of their ability to copy actions, ex. even human actions.
Here are some of the recorded examples of orangutans copying human actions :
Hammering nails into wood
Anointing the body with insect repellent
Attempting to siphon liquid with a hose
Self-Awareness Guided by the fact that self-awareness is an indicator of a certain level of intelligence, researchers usually use a mirror test as an instrument to understand whether animals are aware of themselves.
Orangutans have passed this test.
So why do we use self-awareness as a measure of intelligence?
We do so because we assume that animals that are aware of themselves may also have a better, more conscious understanding of the world around them.
In other words, if they are aware of their own existence, they may also perhaps imagine themselves as separate entities within their own environment as well as in relation to other individuals inhabiting this environment.
Tool Use There are many good examples that demonstrate how efficient these animals may be at using and manufacturing tools.
For instance, they can:
use leaves as “toilet paper”
use vegetation to protect themselves from the rain
use leafy branches as fly swatters
As for tool manufacture, wild orangutans can:
modify sticks to collect insects or open large fruit and seed pods
use stacks of leaves for holding spiny fruit while opening it
and captive orangutans can:
connect short sticks to make one long stick to reach an object
stack boxes to make a ladder
dig holes with sticks
make swings from ropes
collect water using different objects as cups
Planning Traveling around the forest and obtaining food is the main activity that orangutans engage in during the daytime.
Some time ago it was suggested that they develop cognitive maps – memorized knowledge of their habitats – and use them for travel.
They travel by swinging and often use the back-and-forth oscillation of the tree until they can catch another tree.
Deciding and following a potential route through a multitude of trees is a very difficult task. This is especially true for males who are quite heavy – the choice of a wrong tree would result in a fall and serious injury.
So to be successful in their travels they need to take the right decisions about which trees to use and which ones to avoid.
This points to their ability to plan ahead.
Language Finally, language is probably one of the strongest indicators of intelligence – one's ability to understand and respond to the outside world in a meaningful way.
It has been shown these endangered animals can effectively learn to use the sign language.
An orangutan named Chantek has a vocabulary of several hundred signs and understands spoken English and American Sign Language. He can even invent signs of his own.
It is obvious that orangutans are capable learners.
Birute Galdikas says that they can learn how to use language at the level of a 3-year-old child.
— PIGS —
As Smart as the Primates
Intelligence research was done with pigs in the 1990s. One of the experiments was to train the pigs to move the cursor on a video screen with their snouts. When the pigs used the cursors again, they were able to distinguish between the scribbles they already knew, and the scribbles they were seeing for the first time. The pigs learned this skill as fast as the chimpanzees.
All species of pig are smarter than dogs, and capable of abstract representation. “They can hold an icon in their mind, and remember it at a later date,” says Professor Stanley Curtis of Penn State University, who discovered that pigs dominate at video games with joy sticks. Curtis goes on to say, “Pigs are able to focus with an intensity I have never seen in a chimp.”
Smarter Than a Three-Year-Old Child
Other tests were done where the pigs were taught the meaning of simple words and phrases. Several years later, the instructions were repeated, and the pigs still remembered what to do. The same thing was done with different objects placed in front of them. They were taught to jump over, sit by, or retrieve the item. Three years later, they could distinguish between the items.
The studies also showed:
Pigs lead complex social lives that behaviorists once believed to be true only of primates.
Mother pigs sing to their piglets while they are nursing.
They excel at video games that would be hard for a young child, and sometimes better than the primates.
Pigs have a good sense of direction, and can find their way home from long distances.
They learn from watching one another.
Pigs outsmart each other. One will often follow another pig to food before grabbing it away from him, and the pig who was tricked will change behaviors to reduce how many times it is tricked.
Navy dolphins and sea lions
During the Vietnam War, dolphins and sea lions were tapped by the Navy for assistance in duties ranging from mine detection and object retrieval to finding and marking enemy swimmers as part of an official U.S. Navy Marine Mammal Program. Since then, the animals in the marine fleet have been sent to other U.S. Navy bases and were deployed to help clear mines from the waters by Umm Qasr during the early stages of the war in Iraq.
None of the animals has ever been injured or killed in the line of duty, according to the Navy.
"We enlisted marine mammals because modern technology has not yet caught up with their innate sensory abilities," LaPuzza said. Dolphins have superior biological sonar that allows them to find mines and swimmers for the Navy, and sea lions have excellent low-light vision and underwater directional hearing capabilities useful for deepwater object retrieval missions and swimmer detection, he said. Also, unlike human divers, both animals can take repeated deep-sea dives without experiencing adverse health effects.
— DOLPHINS —
The high intelligence of the dolphins is regarded as a reaction to the complex marine environment. The dolphin's brain has 2 kg (4.4 pounds), more than a human brain (which has about 1.5 kg or 3.3 pounds) and displays the same complicated grooves pattern. A dolphin weighing 120 kg (280 pounds) has a 1.7 kg (4 pounds) brain. Archaeological data show they have been having these big brains for millions of years. But there are differences between a dolphin and a human brain: in the case of the dolphin, the auditory areas are more developed than in humans (due to their complicated ultrasound sonar used for mapping the environment).The cortex is relatively less developed than in humans and the neuron's density is lower than in terrestrial mammals.
The brain development of the dolphins is attributed to their displacement in all directions (forward, backward, up and down, left-right), the aquatic and aerial life, the speed of movement (enriching the organism in information), developed space orientation, group life and collective hunt (which require a complex behavior and communication system about food, its nature, size, distance), protein rich food and long parenting of the offspring.
The QE (encephalization coefficient) (volume of the brain versus body surface) is about 2. In lower mammals (like mice) this value falls under 1; in humans is 7.4, in chimpanzee 2.5, in primitive river dolphins 1.5 while large dolphins display a value of 5.6, explaining their developed mental and imprinting abilities. The most developed area are auditory nuclei of the mid brain, the motor nuclei of the fore brain and the motor learning nuclei of the cerebellum.
Their visual areas are less developed than in people`s case, while olfactory areas are completely absent (in humans, they are greatly reduced, but existent). But their cortex, the brain part of mental and cognitive processes, has the same size like in humans and its surface is even more complicated and grooved than in humans. Anyhow, their intelligence and the way they perceive the world are different from ours; their world is a more acoustic one. And even if dolphins can execute complicated movements, they require a long time to distinguish a circle from a square, an easy task for a mouse or a pigeon.
Diver Snaps First Photo of Fish Using Tools
While exploring Australia's Great Barrier Reef, professional diver Scott Gardner heard an odd cracking sound and swam over to investigate. What he found was a footlong blackspot tuskfish (Choerodon schoenleinii) holding a clam in its mouth and whacking it against a rock. Soon the shell gave way, and the fish gobbled up the bivalve, spat out the shell fragments, and swam off.
The tuskfish caught on camera was clearly quite skilled at its task, "landing absolutely pinpoint blows" with the shell, Brown says. A scattering of crushed shells around its anvil rock suggests that Gardner didn't just stumble upon the fish during its original eureka moment. In fact, numerous such shell middens are visible around the reef. Blackspot tuskfish, members of the wrasse family, are popular food fish, so it's surprising that its shell-smashing behavior has remained unknown, Brown says. "My feeling is that when we go out and really look for it, it'll turn out to be common."
The use of a rock as an anvil rather than a hammer could be considered a sign of intelligence considering the ineffectiveness of manipulating a freely suspended tool in water.