Copyright © 2007-2017 Russ Dewey
Lorenz and Tinbergen usually studied solitary animals (monads ) and pairs of animals (dyads ). Starting in the 1960s, researchers started to put more emphasis on social interactions between animals.
John Crook of the University of Bristol proposed the term social ethology to describe this emphasis in animal research (Crook, 1970). The new ethologists focused on several ways that animals can interact:
What do social ethologists study?
Social ethology includes predator/prey interactions, displays such as alarm responses, and competitions for status and territory. All have implications for reproduction, so instinctive tendencies in these areas are strong.
Ethologists study friendly or prosocial behavior (e.g. invitation displays, grooming, and play). They study the reproductive cycle: courting, mating, and raising offspring.
Probably the best way to avoid being eaten by a predator is to avoid it. The slap of the beaver's tail, the flash of a white tail-patch of a deer, the "chip chip" of a bird, the scolding of a squirrel—all are alarm responses. They warn of danger, allowing prey animals to flee.
Vervet monkeys give at least three distinct alarm calls for three different predators: leopards, eagles and snakes. The alarm signals lead to distinct behavioral responses.
Seyfarth and colleagues (1980) played tape recordings of alarm calls to a group of free-ranging (non-captive) vervets. The leopard-type alarm call made the monkeys run into trees. The eagle-type alarm call made them look up at the sky. The snake-type alarm call made them look down to the ground.
This unexpected finding led to research documenting variable and informative alarm calls in many species. For example, the black-capped chickadee, a bird commonly found in American neighborhoods, varies its alarm call depending on the predator, and its alarm call is understood by other birds such as nuthatches.
What did researchers discover about alarm calls of vervet monkeys?
When a chickadee sees a predator, it issues warning call–a soft "seet" for a flying hawk, owl or falcon, or a loud "chick-a-dee-dee-dee" for a perched predator.
The "chick-a-dee" call can have 10 to 15 "dees" at the end and varies in sound to encode information on the type of predator (Schmid, 2007)
What is the benefit of shared alarm responses, among different species?
Alarm responses are often shared by several species. This benefits every animal that participates in the shared alarm system (usually a group of prey animals). The result is an alarm system more sensitive than any one species could provide on its own.
Watering holes on the African savanna are visited by all sorts of prey animals, such as baboons, birds, and cattle. All are threatened by the area's chief predator: the lion. When a member of any prey species senses the approach of a lion, it makes an alarm call, and all the prey species flee.
How do humans participate in shared alarm calls?
Humans participate in a variety of shared alarm calls. A watchdog shares its alarm call with its owner when it barks at shadowy objects in the night. Pet birds and cats also warn their owners of intruders or dangers, on occasion.
Burden (1975) collected a "bulging file" of newspaper clippings about cat heroes.
Take a family in Lewiston, Idaho, whose mistress decided to take a nap in the middle of the day. About two hours later her pet cat Tiger roused her with loud and anxious mewing. Following Tiger into the spare bedroom, the lady found pieces of ceiling falling onto the floor in flames. She managed to rescue Tiger and her kittens, but it was only a matter of minutes before the whole house went up in flames.
The woman probably lost many valuables in her house, but she saved the cat and her kittens. This helps answer the question, "What's in it for the cat?"
What is the human alarm response?
The human alarm call is the scream. It emerges in stereotyped form, without learning, in normal members of our species.
Small children commonly scream as an involuntary response to play situations, such as being approached by an adult playing the role of a monster. Like other species' alarm responses, a scream can be detected at a large distance, providing a useful warning.
Animals commonly stake out a territory and defend it. Studies of nest spacing and population control show how population may be regulated by available territory for nesting and breeding.
Some birds nest differently depending on available space and population density. Rodents will reproduce in different numbers depending on available resources.
How common is competition for territory, in nature?
Ants have territorial battles. One species in the Southwest United States has "tournaments" during which different ant colonies meet at the boundaries of their territories.
They engage in mock combat, drumming on each other's abdomens with their antennae. After 10 to 30 seconds, one or the other ant yields ground and the encounter ends.
In this way, territorial boundaries are re-established with a minimum of actual fighting (Rossiter, 1976).
Group-living animals commonly joust for dominance. Different animals test each other to see who is "really boss."
The outcome has important implications for each animal's genetic success. Dominant animals usually reproduce more than non-dominant animals.
Aggression in primates is related to the male hormone testosterone. The more testosterone a male primate has, the more aggressive it tends to be. Defeated males lose testosterone.
How do struggles for dominance relate to the male hormone testosterone, in primates?
Similar phenomena occur in other mammals. A dominant ram mates repeatedly with his pick of the ewes. The male that loses a head-butting contest might not reproduce at all.
What does Pryor say about the nature of porpoises?
Karen Pryor is the famous porpoise researcher whose differential reinforcement of creative behavior in the porpoise was described in Chapter 5. She noted that people think porpoises are "cute, playful, friendly, harmless and affectionate to each other and to man." The truth is that they engage in constant struggles for dominance.
The novice trainer quickly learns that porpoises can be very aggressive. They are highly social animals, to which rank order is a matter of considerable importance.
Aggressive interactions between porpoises, usually during dominance disputes, include striking, raking with the teeth, and ramming with the beak or rostrum. Sometimes there are serious consequences, such as broken ribs or vertebrae, or punctured lungs.
A dolphin accustomed to humans shows no hesitance in challenging the human for dominance, by means of threat displays and blows. A person who is in the water with an aggressive porpoise is at a dangerous disadvantage.
The sentimental view that these animals are harmless stems at least in part from the fact that they are usually in the water and we are usually on boats or dry land. They can't get at us. (Pryor, 1981)
How do chimpanzees "test" human lab assistants?
Sarah Boysen, a chimpanzee expert, made a similar point. She said chimpanzees "test" human lab assistants with dominance displays such as roughhousing and hair pulling. Chimps also seem to be sensitive to gender differences in humans.
Boysen noticed that the chimpanzees seldom bother male lab assistants who are physically large, especially if they have facial hair such as beards. But the chimpanzees challenge female lab assistants "constantly, every day." (Boysen, personal communication).
Angry or aggressive-looking postures, noises and facial expressions are widespread among different animal species. Displays often serve as a substitute for actual fighting.
One of the most common threat displays is the stare. "Animals as diverse as crabs, lizards, and birds all perceive staring as a threat." (Kalin, 1993) This is one reason people are advised never to stare at potentially hostile dogs. Or bears.
What is the function of threat displays? What are common examples? How did Dian Fossey use a facial expression to intimidate a large gorilla?
When a larger or more dominant animal makes a threat display, a younger or more submissive animal usually backs down, and violence is averted. A low growl accompanied by a stare is an unmistakable threat display used by many large mammals.
A common threat display for the dog is a low growl, with ears laid back and teeth bared. Cats have a threat display also: they stare, make a low growling sound, and adopt a posture that indicates they may attack.
If seriously threatened, cats hiss, arch their backs, and fluff their fur in the classic "cat fight" posture. Such a display might be considered a fear display as much as a threat display. Fear and threat displays are often similar.
A primate grimace known as a threat face tells an aggressor to "back off." Dr. Dian Fossey, whose life was portrayed in the movie Gorillas in the Mist, used her knowledge of social displays among gorillas.
In response to a silverback that would not stop bluff-charging her, she made a fright face, [a] kind of horrible grimace... The startled silverback sat down at once and began to eat, nervously, with one eye on her. Then he got up and walked away. (Willis, 1990)
How are intention movements used in threat displays?
Many threat displays involve intention movements: movements that indicate the animal is getting ready for an action. In humans, a threatening intention movement is the clenched fist.
In seagulls the threat posture is an upright head, ready to give a sharp peck. Cats, when bothered, swat with their paws, in a minor version of attack behavior that (when full-fledged) is deadly to small prey.
Cats who are annoyed may also open their mouths, looking ready to bite. They may administer a soft "mock bite" that does not break skin but conveys an unmistakable message: "Stop what you are doing." Mother cats do the same thing to kittens.
How do intention movements trigger avoidance behavior?
Intention movements show how conditioning can operate in a natural setting. An intention movement is a signal that a punishing event is about to occur, just as surely as a buzzer that occurs before an electric shock.
After receiving discipline, a subordinate animal learns to avoid such punishment in the future by executing some behavior such as backing down. Viewed through the lens of operant conditioning, this is avoidance conditioning.
A German Shepherd trainer who specialized in problem cases said his technique for greeting a disobedient dog was to clasp the dog's head and stare it in the eye until the dog looked away, indicating submission. That established who was boss. The trainer was large and strong, which probably helped.
Cesar Millan, the "Dog Whisperer" who hosted a program of that name for years, would sometimes pin a dog to the ground at the neck, the way a dominant wolf treated a subordinate wolf. Cesar used his hands instead of his teeth, but the message was the same: I'm the boss, stop misbehaving.
Dogs responded to this display of dominance almost every time. Cesar's strength and calm but firm manner contributed to his uncanny success with problem dogs.
What actions can tell a dog who is boss? How do group-living and solitary animals differ, regarding submission to authority?
Not all animals respond so readily to assertions of authority. As a rule, only group-living animals are programmed to submit to dominant animals.
In group-living species, submission is adaptive; it gives the subordinate animal better odds of survival and reproduction. Badgers, by contrast, are solitary animals.
Therefore badgers are not programmed to respond to submit. They do not respond well to acts of discipline by a human. Eibl-Eibesfeldt wrote:
When I reared a badger I could never forbid it to do anything. If I scolded it when it opened a cupboard and pulled out my linen, the most it did was to stare at me, and if I gave it a smack on its nose it attacked me. It would not subordinate itself. A dog, on the other hand, quickly learns to obey. (Eibl-Eibesfeldt, 1970)
Submission postures are displays used to acknowledge a dominant animal and ward off aggression. The submission posture conveys the message, "OK, you're bigger. I am no threat to you. You do not have to injure me."
Dogs (as well as humans) cringe and cower as symbols of submission. When dogs fight, the fight always ends the same way: the loser turns over on its back to signal submission.
We once had a little dog (a Jack Russell terrier) who did not wait for a fight; whenever she met another dog, she flipped over on her back right away. The gesture worked; she never had to fight.
What is the function of a submission posture? What are similar human gestures?
Submission postures often involve exposing a vulnerable part of the body such as the neck. A supplicant bowing before a king illustrates a submission posture.
In the kneeling position, a person is vulnerable to being struck on the neck or back of the head. The kowtow of medieval China was an extreme example; visitors to the emperor literally threw themselves to the ground, touching it with their foreheads.
Bowing remains a gesture of respect in many countries today. To Muslims, touching the forehead to the ground is a way of showing submission to Allah.
Submission postures are called appeasement displays if used to appease (lessen the anger of) an aggressive animal. A striking characteristic of animal and human appeasement strategies is infantilization.
Cowering, whining, crying, begging, and nervous laughter: all are responses that partially mimic the behavior of children. These postures are often accompanied by a higher voice, similar to a child.
What is an appeasement display? How are such displays infantilized?
Smiling itself, ethologists suggest, is an infantilized expression, more typical of children than adults in most primate species. Chimps, like humans, smile and cringe when confronted with a dominant, aggressive animal.
Burden, J. P. (1975, November) Hero Cats. Glamour, p.15.
Crook, J. H. (Ed.) (1970) Social Behaviour in Birds and Mammals: Essays on the Social Ethology of Animals and Man. Cambridge, MA: Academic Press.
Eibl-Eibesfeldt, I. (1970) Ethology, the Biology of Behavior. Austin, TX: Holt, Rinehart & Winston.
Kalin, N. H. (1993, May). The neurobiology of fear. Scientific American, pp.94-101.
Pryor, K. (1981, April). The Rhino likes violets. Psychology Today, pp.92-98.
Schmid, R. E. (2007, March 20) Nuthatches Seem to Understand Chickadee. Retrieved from: http://www.washingtonpost.com/
Seyfarth, R. M., Cheney, D. L., & Marler, P. (1980). Vervet monkey alarm calls: semantic communication in a free-ranging primate. Animal Behavior, 28, 1070-1094.
Willis, D. (1990, July 15) 'Some Primates Weren't to be Trusted.' Review of H.T.P. Hayes, The Dark Romance of Dian Fossey. New York Times Book Review. Retrieved from: http://www.nytimes.com/
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Copyright © 2007-2017 Russ Dewey