Vol. VIII • 1986 http://www.creationism.org/csshs/v08n4p28.htm
Creation Evidences from Animal Learning Research
Diane Powell
Creation Evidences from Animal Learning Research
Diane Powell
Research along the lines of general process theory has been going on for over sixty years and has uncovered certain general laws of learning. For example, there is a similar learning gradient for a wide range of learning tasks, including such things as galvanic skin response IGSRI and salivation.1 However, while general process theory has produced certain general laws about learning which hold true across systems and species, it has also provided an inaccurate view of the behavior of any particular species. It has done so by overgeneralizing and thus obscuring the unique nature of each created kind. This uniqueness is significant because it testifies to the greatness of the God who created all things and called each of them "good".
In order to meet the experimental demands of general process theory, B.F. Skinner designed an experimental "box" which was able to record an animal's responses to arbitrarily chosen stimuli. The box housed food and water containers, a light and a screen and was fitted with a lever which, when pressed, recorded the response. Although the incidence of the response was accurately recorded by this convenient procedure, other factors such as motivation were totally ignored. Through such gross oversimplification, learning theorists were totally ignoring the true nature of the animal's responses.
In one operant experiment cats were exposed to a puzzle box containing a pole.2 When it was tilted in any direction, the doors opened allowing the cat to reach the food just outside. A Skinnerian type recording device would have recorded onlythat a response was made. However, this experiment involved a human observer who noted that the cats displayed certain stereotyped response patterns, moving the pole with a paw for a while and then using the shoulder or even the whole body.
The significance of these responses was not noticed for several years until Bruce Moore spotted it.3 He replicated the cat study done by Guthrie and Horton using either a human observer or a TV camera and was able to determine that the cats were responding only when a human observer was present. Furthermore, they were responding in a manner that was a typical social greeting. When Guthrie and Horton tried dogs in the same experiment, the dogs responded only by whining. The experimenters had ignored the possibility that the cat's responses were social and a feature unique to that organism.
Today, there is an increasing amount of evidence which challenges general process theory. There are more and more indications that, rather than being plastic and moldable, learning is itself shaped by an underlying structure which is unique to the organism and which determines the prospect of that learning task. Bolles discusses the term "preparedness" as an alternative to the concept that all responses are equally possible.4 Preparedness refers to capabilities which are innately programmed. These determine to a large extent what can be learned, and the ease with which it can be learned. Preparedness is assumed to be relative, identified by such terms as preparedness, unpreparedness, and contrapreparedness.
In avoidance conditioning the rat is prepared to learn to run down an alley for its escape, thus the learning of such a task proceeds rapidly. However, if the experiment requires something for which the animal is unprepared, such as running to the side of a shuttle box, the learning may require a long time if it is possible at all. In the case of contrapreparedness the task requires something that is contrary to what the animal is naturally prepared to do, something the animal finds it nearly impossible to learn. Although Bolles is still thinking in terms of a preparedness arrived at through evolutionary changes, the concept of preparedness is consistent with the concept of design implied by Creation.
John Garcia and his colleagues have seriously challenged both the notion that all associations are equally possible as well as the importance of there being no more than a very short delay between the response and the reinforcement. During experiments involving conditioning an avoidance to water, Garcia discovered that while rats could learn to associate lights and noise with foot shock, they could not associate lights and noise with nausea produced by radiation or toxin,6
Garcia designed a novel apparatus such that when the rat's tongue licked a waterspout, a circuit was completed which delivered stimuli of flashing lights and noise. Garcia found that the rats could readily associate taste stimuli such as saccharin flavored water with nausea but were unable to associate such tastes with foot shock. This ability to make a quick association between taste and subsequent illness is so remarkable it has been labeled the "Garcia effect." This ease of association between a certain kind of causal agent with a certain class of effects indicates a preparedness. This principle of "belongingness" has been likened to such innate detection systems as the "bug detectors" of the frog6 and the "bat detectors" in the auditory system of the moth.7
In earlier learning experiments delays of 3 to 45 seconds have appeared to interfere with learning. However, Garcia has demonstrated a significant effect after delays of 75 minutes when rats were given a drug which produces gastric distress. This followed the ingestion of saccharin water.9 In another laboratory, Revusky produced aversion to sucrose when x-ray exposure had been delayed seven hours.9 Smith and Roll demonstrated similar effects for saccharin and radiation after a twelve hour delay.10 Conditioning success in spite of delay indicates that general process theory is inadequate as an explanation of behavior. In addition to this, a creationist explanation would predict such a talent in an animal that functions as an opportunistic forager. The lowly rat is far more capable than learning theorists have given him credit for.
Another experiment indicates thai rats are able to respond to subtle taste cues, another feature we would expect in an organism created to forage. Exposure to low dosages of radiation for eight hours in special radiation chambers was seen to cause a depression in food and water intake during exposure.11 The following week the animals were returned to the radiation chambers and tested without exposure to radiation. The animals displayed the same depressed food and water intake. Later, informal testing revealed that the animals were responding to subtle taste cues which had been conditionally associated with radiation exposure. It seems that they were refusing water which had stood overnight in plastic test bottles such as were used in the radiation chambers. Later work confirmed that visual, auditory and tactile stimuli associated with the distinctive compartment were ineffective as conditioning variables.12
Another example of the rat's God-given talents is his sensitivity to a thiamine deficiency, which prompts him to sample newfoods. It has been demonstrated that rats will learn an aversion to a familiar but deficient diet. Later, even when hungry and recovered from the effects of the former diet, they will prefer not to eat ifthe deficient food is all that is available.13 Rats also learned to prefer a flavor which was associated with recovery from a thiamine deficiency.14 Thus, they are prepared by design to avoid malnutrition.
In summary, the food behavior of the rat exhibits the features which we would expect of a creature designed to forage. The rat has an innate capacity to associate subtle food tastes with nausea even after long delays. Though such instinctive behaviors are predicted by the creation assumption they boldly contradict much of what learning theorists have believed for many years. Such a preparedness can also be seen in the area of avoidance behavior. Bolles points out that natural avoidance behavior has little to do with avoidance as it is usually studied in the laboratory. For example, an escaping mouse has no chance to "learn" proper avoidance behavior. It must knowwhat to do if it is to remain alive. Instead it is kept alive not by learning but by an innate defense reaction to new and sudden stimuli.
When laboratory rats are shocked, their friendly inquisitive natures are dramatically transformed into what resembles a wild rat, furtive and bent on escape. Exploratory, grooming or appetitive behaviors such as bar pressing all drop out. This sudden severe restriction of its activity to species specific defense responses is highly serviceable, as it promotes the animal's survival. However. it indicates that an organism's survival depends upon its own instinctive preparation and how well the animal conforms to it rather than on its own creative responses.
Bolles proposes that a response can be rapidly acquired only if it is a Species Specific Defense Response (SSDR}. For example, if the innate fleeing response is effective in a particular experimental set-up it will be acquired rapidly. For example, running down an alley may require six trials to learn whereas jumping out of a box may require only a few trials, perhaps only one.15 These may both be considered examples of preparedness. On the other hand, learning the appropriate response in a shuttle box may require 100 trials if it is learned at all.
Bolles also argues thai a response can be rapidly acquired only by the suppression of other SSDR's. For example, other innate escape behavior such as freezing and aggression only result in more shock, thus they are suppressed. Running and jumping are acquired quickly only if they make flight possible. Thus, establishing an avoidance response depends upon how well the instinctive need for flight is being met, not on the response's physical features or even its effectiveness in avoiding shock.
Thus we see evidence for the innate structure of learning both in eating and in escape behavior. Survival may depend not so much on how clever the animal is, but on certain stereotypic inborn mechanisms designed to promote its survival and how well the animal heeds its natural instincts. Those who defend the notion "survival of the fittest" must give serious attention to this claim: The fittest animal is the one who is most true to the pattern of its created kind. Those animals who are "different" are not better equipped behaviorally or genetically.
Other investigations indicate that the preparation is a biological one. For example, aversions have been produced even while the animal was anesthetized.18 17 Others also have stated that humoral changes must be responsible for the aversive properties of x-radiation.19 Other studies have shown taste aversion learning while the cortex was inactivated by cortical spreading depression.20 Aversive effects can even be induced by transfusions of blood from irradiated donors.20 Such evidence suggests strongly that the basis for innate learning mechanisms may very well be biological.
Such evidences of innate biological preparation for behavior point clearly to the concept of design. We may praise the Creator that even the lowly rat benefits uniquely from the loving design of its Maker. Such a humble example only bears further testimony to the wisdom and love of our Heavenly Father.
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