Instinctive Behaviors

Web making by spiders is an example of a genetically determined or instinctive behavior. There is little variation between individuals in how they construct the web and it is constructed similarly each time they do it. Ethologists (people who study behavior) call such a behavior a fixed action pattern. Fixed action patterns do not require learning or prior experience for their expression. They can, however, be very complex.  For example it has been noted that a cocoon-spinning spider performs over 6000 individual movements in a virtually identical fashion each time it prepares and closes its cocoon.

Fixed action patterns cannot be identified solely because they are highly stereotypic and species-specific. For example, songs of bird species fit those criteria but are actually learned behaviors, not instinctive behaviors. Birds deprived of the experience of hearing the song do not produce the characteristic song pattern. Deprivation experiments in which animals are raised without parents,or contact with their own species, have typically been used to help distinguish a behavior that is a fixed action pattern from those which are learned.

The lack of expression of a behavior in a deprivation study does not necessarily mean that it is not genetically determined. It may mean that the requisite stimuli are absent. Stimuli to elicit the expression of fixed action patterns are called releasers. Also a fixed action pattern may not be displayed because the animal is not in the appropriate physiological or developmental state. For example courtship behaviors are not shown by pre-pubertal animals even if the appropriate releasers are present.

Learned behaviors.

Learning is the modification of behavior in response to specific experiences. Learned behaviors of animals can be classified in various ways:

In Associative Learning an animal learns to associate one stimulus with another. There are 2 forms of associative learning. The first is described as classical conditioning and was demonstrated by Pavlov in his famous dog experiments. First he stimulated dogs to salivate by rubbing meat powder on their lips. The meat powder odor stimulated salivation as a physiological process. He then "conditioned " dogs by ringing a bell, or a tuning fork, at the same time as applying the meat powder. He then demonstrated that the animals had become conditioned to associate the sound of the bell with the meat powder and would salivate to the noise without food present.  A second form of associative learning  is called operant conditioning. In operant conditioning  an animal conducts a chance action e.g. pressing a lever and is rewarded with food. Rapidly the animal learns that the action leads to a food reward and will carry out the behavior repeatedly for food. This is the type of approach applied in most animal training.

Observational learning or modelling is when the animal learns a behavior through watching other animals conduct the behavior. For example,in a pack animal such as the wolf, hunting behaviors, fit this category.

Insight learning is in a sense the  "highest form" of learning observed. It is the ability to problem solve or to perform a correct or appropriate behavior the first time the animal is exposed to a situation. For example a chimpanzee may stack boxes to obtain a food object hung out of its reach without ever having seen this solution to the problem before. However, it is not restricted to primates e.g. Ravens and other birds will also show insight learning.

An animal may cease to carry out a response to a stimulus if the appropariet response no longer occurs. For example using the operant conditioning example given above if pressing the lever no longer leads to a food reward the behavior will probably become less frequent and stop.

 
Nature versus Nurture.

A debate among human psychologists, as well as animal behaviorists, concerns the relative importance of instinctive and learned behaviors. The factor influencing learned behaviors is the environment in which the animal is placed.   This debate is often referred to as Nature (genes) versus nurture (environment).

The balance between fixed and learned behaviors varies with species. In humans, a large part of our behaviors are learned. In the absence of role models to learn from (deprivation) there is a greater emphasis on programmed behaviors. Some behaviors need to be fixed for survival because there is unlikely to be a second chance to learn them. For example the kangaroo rat instinctively reacts to the sound of a rattlesnake by executing an escape jump. This is a species specific defense response.

With learned behaviors there ar often  critical or sensitive periods for the development of the appropriate learned behavior. For example a dog that has not been socialized to humans by 14 weeks of age is unlikely to be a good pet. Dogs that have not been well socialized to other dogs may be frightened of them or will not breed with them.

Imprinting is another example of a process that must occur within a distinct, usually short, time period. It is also irreversible and involves an attachment to an object that will evoke subsequentadult behaviors and can be generalized to all examples of the object.
The classic example is the work of Lorenz with goslings in which they imprinted on Lorenz. The imprinted adult geese directed courtship behavior to Lorenz rather than other geese.

Konrad Lorenz.  Nobel Laureate
 

Animal Cognition

Cognition is the ability to think. When applied in the context of animal behavior it refers to the ability of an animal to be aware of and make judgements about its environment. Are animals conscious of themselves and their place in the world? Do they feel pain, pleasure and sadness in the same way as humans? Are the differences between animals and humans in cognitive ability absolute, as believed by Descartes, or a matter of degree? Professor Donald Griffin of Princeton has been a proponent of the concept of cognitive ethology. This views conscious thinking as an inherent and essential part of the behavior of many non-human animals. Conscious thinking has been demonstrated in non-human primates but it is a very difficult subject to study with scientific rigor. As we have discussed above very many complex behaviors are actually genetically determined or learned by simple associations that do not need cognition. Difficult though they are to study the answers to questions about animal cognition may profoundly affect our views on the treatment of animals and their welfare.

Follow the link to an article on animal thinking by Pam Noble entitled the Status of the Animal Mind
 

Communication

Communication among animals relies upon their abilities to perceive sensory information. This may be visual, auditory or olfactory. Domestic animals perceive the world in a different fashion to us so may respond differently also.

Vision - An obvious example of  seeing the world differently relates to eye placement. Horses are set laterally, providing a wide range of monocular vision (215 degrees) but a small 60-70 degree arc of binocular vision. In contrast, the cat has a much smaller arc of vision (around 180 degree) because of the placement of the eyes to the front but more than half of this is binocular vision. When the relative visual acuity of domestic animals is compared, the ranking is pig, sheep, cattle, dogs and horses. All the domestic animals have some ability to discriminate colors and most have superior night vision to humans.

Auditory sensing - Again there are differing ranges of hearing, as well as different acuities. Sheep and dogs can discriminate higher frequencies than humans. Cats range of hearing is similar to humans.

Olfactory senses - This is perhaps the most important sense of domestic animals in terms of communication. Dogs probably have the greatest olfactory ability of the domestic species. They are able to detect many compounds at 1/100 the concentration of humans and for many weeks after they were placed. Odors and pheremones are very important triggers for domestic animal behavior.

The communication methods employed by an animal in response to stimuli perceived through these sense organs are  the same types: auditory, visual (facial expressions, posture, grooming) , and olfactory. These communication methods have varying importance between domestic species:

Auditory - Pigs have perhaps the most complex set of domestic animal vocal sounds - more than 20 distinct types have been identified. Horses, cats and dogs also have many sounds but those of cattle and sheep have been little studied. The categories of calls include greeting, distress, separation, excitement, aggression, fear, pain and so on.

Visual - In the horse, for example, the ear position can tell a lot about the animals disposition. Ears pointed back generally denote aggression and the flatter the ears to the head the greater the aggression. Another visual expression in male horses and ruminants is the Flehmen response. This is a curl of the lip when the urine of a female in estrus is smelled. In the cat, a high tail is a greeting or sign of being curious. Raised hackles, and lips drawn back in the dog denotes aggression; if  the ears are flat against the head and the tail is between the legs this signifies fear. Pigs and horses show grooming behavior, as do many of the monkeys and primates. Subordinate pigs groom dominant ones. Horses tend to groom horses of comparable rank. Cattle and cats spend long periods of time self-grooming but little time grooming others. Subordinate cattle will lick dominant cattle.

Olfactory - Olfactory clues and scent serve to mark territory , show the way home, and distinguish individuals. Urine and feces are powerful means of olfactory communication. Cats and dogs also have anal sacs which are additional scent organs. Olfactory stimuli play a major part in heat detection in cattle, and for distinguishing animals. The ewe will accept an orphaned lamb if it is made to smell like her own lamb.

                  Animal Behavior and the Animal Scientist.

Domestic animals display the same ranges of behaviors that would be seen in other animals and have both instinctive and learned behaviors. Understanding domestic animal behavior is not only fascinating and intellectually stimulating it is also crucial in their management, productivity and welfare.
 

Behavior and the detection of animal disease.

Often the experienced veterinarian or owner who has a sound understanding of  normal animal behavior can identify the existence of a problem from a change in posture, sounds etc. Some are very easy to recognize such as acute laminitis others can be quite subtle. An animal kicking at its belly probably has an abdominal pain, while sweating in horses is a sign of acute pain e.g. colic. Dogs with ear infections often tilt their heads. Excessive grooming or scratching is indicative of parasites or irritations. A change in the order in which an animal comes into the milking parlor, particularly if a dominant cows hangs back, may indicate illness.

Control of Breeding and Feeding

The definition of a domestic animal is one which has been altered by selective breeding and control of the food supply by humans.  An understanding of behavior allows the detection of animals in heat, can be used to identify feeding problems, modify maternal behavior to accept orphaned animals, manipulate  group numbers and size of animals to reduce aggresion and so on.

Training

In training domestic animals heavy reliance is placed upon associative conditioning i.e., positive reinforcement of desired behaviors,  but the genetic blueprint is also very important. For example the genetic predisposition of the border collie to herd is adapted by consistent training to  increase skills and control of that instinctive ability. This is a particularly crucial aspect of  animal science with respect to the companion and recreation species. The use learning theory is also applied to help animals relearn to reduce vices and bad habits.

Behavior and the Environment

Observation of animal behavior provides a great deal of information about the extent to which the animal copes with the environment in which they are kept.  It can also contribute to the design of better housing and management systems for farm animals. An obvious example is climate. Temperatures which are either too hot or too cold will lead to behavioral changes which are readily detectable. If dairy cows are standing in free stalls  rather than feeding or lying down it probably indicates that the stalls are uncomfortable. If the environment of pigs is very barren and unstimulating  this will lead to some aberrant behaviors such as aggresion and also to stereotypes. This is discussed further under the animal welfare section.

 
Bibliography

Craig, James. (1981). Domestic Animal behavior: Causes and Implications for Animal Care and Management.  Prentice-Hall;, Inc. Englewood Cliffes, New Jersey

Houpt, Katherine. (1991) Domestic Animal Behavior for Veterinarians and Animal Scientists. Iowa  State Press, Ames,  Iowa,

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