Feeding Behavior In Feral And Domestic Cats Essay, Research Paper

Feeding Behavior in Feral and Domestic Cats

During the course of evolution, a species may change drastically. Adaptations in

behavior and in physical characteristics are both important to survival. Some behaviors of

a species may be learned, while others may be genetically determined. It is likely that most

behavior are a combination of genetic makeup and learning. Learned behaviors are

essential to survival because they can change to meet the demands an organism?s current

situation. Genetically determined behaviors are advantageous because they are automatic

and take place in the absence of learning. Each of these types of behavior are important to

species survival.

One way of conceptualizing genetically determined behaviors is through the Fixed

Action Pattern. Fixed Action Patterns or FAP?s are species typical behaviors that are

stereotyped, they are independent of external control, spontaneous, and are independent of

individual learning (Moltz, 1965). Fixed action patterns are considered to be

consummatory acts, and include a wide range of different behaviors.

Some types of feeding behaviors can be considered to be FAP?s. Capturing and

consuming prey are probably two of the most important behaviors an animal must perform

in order to survive. In most species, the young must learn how to capture prey from it?s

parents. This is especially true for carnivores.

Carnivores must work especially hard for their food. In most cases, carnivores

species must locate, capture, and kill their food before they can begin to feed. Herbivores

usually need only to locate a food source. One species of carnivores that is in fairly close

contact with humans is the domestic cat. Domestic cats belong to the family felidae,

which also includes large felines such as tigers, leopards, and lions. It is estimated that as

many as 31.2 million families out of the 108

Large felines, such as lions, hunt and kill food in groups. Some other large felines

are solitary hunters. The common, domestic cat is also a solitary hunter. Typically,

domestic cats stalk their prey in a manner that is stereotypical of most domestic cats. A

study by Hutchinson and Renfrew (1966) looked at physiological factors that affected the

stalking attack in domestic cats. In that study, cats were placed in a testing area along

with a mouse. In each trial, different areas of the hypothalamus were stimulated. The cats

moved about the test space quickly and quietly with their backs arched while they sniffed

at the floor. Upon approaching the rat, the cat lunges and takes it?s prey by the back of

the neck and holds it to the floor with one paw. This study found that stalking behavior of

this manner could be elicited by stimulating the lateral areas of the hypothalamus. This

area of the brain plays a role in controlling when an organism is hungry or thirsty. Since

stalking behavior can be elicited by stimulating a certain area of the brain, it is reasonable

to assume that this behavior is a hard-wired, genetically determined behavior. However,

some parts of this behavior may also be learned. Hutchinson and Renfrew do not address

the learning component of the behavior.

Another type of behavior that is observed in cats is the tendency to shake their

heads back and forth while eating. This behavior has no real use when the cat is eating a

meal, such as commercially produced cat food. However, if the cat were attempting to

kill a smaller animal for food, the behavior has a definite purpose. When killing prey, cats

typically grab the animal at the back of the skull, at it?s base, and shake it back in forth.

This action helps kill the cat?s prey more quickly. The fact that this behavior is observed

in many different species of cats suggests that it may be genetically determined and

therefore passed on as the species evolved. It is also reasonable to assume that as

domestic cats become more dependent on humans to provide them with food, and less

dependent on their hunting skills, that fewer instances of this behavior will be observed in

domestic cats than in feral cats.

Domestic cats, in some cases, will hunt even though they do not need food.

Household pets are commonly observed stalking bugs and other small creatures that are

found in their immediate environment. In some areas, domestic cats are considered a

threat to indigenous wildlife (Liberg, 1984). A study was conducted by Liberg (1984) to

determine what foods house cats in Sweden regularly consumed. It was found that even

though all the cats in the sample were regularly fed by their human owners, they still

continued to hunt during all seasons. During the year when the cats were studied, both

house cats and feral cats were found to have killed similar numbers of animals. While one

would expect that feral cats would have hunted and killed other animals for food much

more often than house cats did, the difference was surprisingly small. The fact that cats

will hunt even when there is food available also suggests that many of the behaviors

associated with hunting and killing prey are genetically determined, and can be passed on.

A study by Adamec (1976) examined the relationship between hunting in cats and

hunger. In that study it was found that domestic cats will stop eating a meal of

commercially produced cat food in order to kill a rat. After they kill the rat, they bring it

back to the bowl of food they were eating, and then continue to eat the cat food. These

results show that hunting behavior and eating are not necessarily related to one another. It

seems that hunting and killing prey is a behavior that is not related to the animal?s

immediate need for food.

It is difficult to directly observe cats hunting prey. However, components of the

behavior can be easily observed in domestic cats. The head shaking behavior of cats can

be observed even when the cat is eating commercially manufactured cat food. This

behavior persists even though it is not necessary useful to the animal. If this behavior is

genetically determined and not learned, it should be present in both feral and domestic

cats. Also, if this part of the behavior is reinforced by hunting and killing prey, it should

be observed to a greater degree in feral cats than in domestic, indoor cats.

Method

The subjects of the experiment were 4 domestic cats and 3 feral cats. The age of

the cats was between 3 and 12 years of age. All four domestic cats were female. One of

the feral cats was female. All of the cats included in the sample had been spayed or

neutered.

Living conditions of the cats varied. Three of the domestic cats lived indoors, and

did not ever go outside. One of the cats lived some of the time indoors and some of the

time outdoors. The three cats that were considered feral cats were placed in that category

for two main reasons. First, they lived exclusively outdoors. Second, they did not allow

humans to approach them at any time.. The other cats in the sample all allowed themselves

to be approached by and at times approached humans. The animals in this category are all

considered to be pets, whereas the others are not.

Some of the cats in the sample were genetically related to one another. Three of

the cats in the sample are littermates. Of these three, two of them are indoor pets, and one

of them was categorized as a feral cat. The only male cat in the sample, one of the feral

cats, had the same mother as these three, but was not from the same litter. The remaining

cats in the sample are not related to one another, or to any of the other cats in the sample.

All of the cats were offered store bought cat food. They were presented with a

choice of either dry or canned food. The feral cats were fed at approximately 5:30 p.m.

everyday. The indoor cats were presented with the same food choices, but were allowed

to eat whenever they wished during the day. Circumstances beyond the experimenter?s

control forbid any manipulation of feeding times or food choices.

The feral cats were observed at their normal feeding time over a period of five

days. The indoor cats were observed at many different times during the day when they

were eating. This was also done for five days. It was not possible to induce the indoor

cats to eat at a regular time during the observation period.

The behavior of interest was head shaking while feeding. Head shaking was

defined as a vigorous shaking of the head from left to right. The shake from left to right

only had to occur once in order to be recorded. Initially, the head shake was defined as

having to happen twice, but was changed. This was because the behavior of interest

turned out to be more rare than expected. Behavior was recorded as either being present

or not present. The number of times that it occurred was also recorded.

Results

Very few instances of the head shaking behavior were observed in any of the cats.

However, it was slightly more common in the feral cats than in the indoor cats. Only two

instances of the behavior were observed in the indoor cats, while six were observed in the

feral cats. The results are presented in Graph 1. These results support the hypothesis.

The cats that did exhibit the head shaking behavior tended to do so most frequently when

eating canned cat food. The behavior was only observed once when a cat was eating dry

cat food, in one of the indoor cats. The cats were observed for a total of approximately 5

hours (1 hour per day). The feral cats were observed more regularly and for longer

periods of time than the indoor cats. The feral cats tended to eat less than the indoor cats,

but ate for longer periods of time. All of the indoor cats ate small amounts of food several

times during the day (probably many more times than could have been observed and

recorded by a single observer). The indoor cats ingaged in another behavior that was

similar to the head shaking behavior. At times, they would tilt their heads to one side

while chewing. This behavior looked almost like half of a head shake.

Discussion

Based on the results, one could assume that head shaking behavior is both

genetically and environmentally determined. Since the feral cats exhibited the behavior

more often, it is possible that it is reinforced though experience with killing prey. The

indoor cats had very little opportunity to hunt anything, so they were not reinforced. The

fact that the behavior is still observed in the indoor cats suggests that it is at least partially

controlled by genetic factors. The results of the study by Hutchinson and Renfrew (1966)

also suggest a biological basis for some of the stalking behavior observed in domestic cats.

Although the hypothesis was supported, this study had many shortcomings. First

of all, the feeding times and food choices of the cats could not be manipulated. The feral

cats and house cats were not always fed the same types of food. Canned cat food was fed

in greater quantities to the feral cats. Dry cat food was available to the indoor cats most

of the time throughout the day. On some days the indoor cats did not receive any canned

cat food at all. All the cats food intake was regulated by someone other than the

experimenter. In most instances, the indoor cats received canned food only when they

made vocal appeals to their caretaker.

Another potential problem with the experiment was that the feral cats were

observed for longer periods of time than the indoor cats. The indoor cats did not have a

specific time when they were fed. This made observations difficult. It is possible that the

indoor cats may have exhibited more instances of the head shaking behavior when they

were not being observed. The indoor cats were aware that they were being observed

during most of the time they were being observed. It was nearly impossible to observe the

indoor cats in an unobtrusive way. However, the feral cats were never aware that they

were being observed.

This study could be improved by reducing the amount of variance between the

feral and indoor cat groups. Uniform diets and feeding times would probably have yielded

different results than what was found in the current study. It would also be interesting to

do another study that examines the degree to which the head shaking behavior is

genetically determined. According to an article by Moltz (1965), fixed action patterns can

occur in the absence of the normal releasing stimulus. In the case of head shaking

behavior in cats the releasing stimulus would be food. If head shaking behavior fits into

the category of fixed action patterns, cats might shake items other than food. Future

studies could look at how frequently cats perform this behavior on nonfood items, such as

toys. Differences between cats who have been food deprived and those who have not

could be compared.

Bibliography

References

Adamec, Robert E. (1976). The Interaction of Hunting and Preying in the Domestic Cat.

Behavioral Biology, 18, (263-272).

Hutchinson, R. R., & Renfrew, J. W. (1966). Stalking Attack and Eating Behaviors

Elicited From the Same Sites in the Hypothalamus. Journal of Comparative and

Physiological Psychology, 61, (360-367).

Liberg, Olof (1984). Food Habits and Prey Impact by Feral and House-Based Domestic

Cats in a Rural Area in Southern Sweden. Journal of Mammalogy, 65, (424-432).

Moltz, Howard (1965). Contemporary Instinct Theory and the Fixed Action Pattern.

Psychological Review, 72, (33-50).