half a century on the concepts of innateness and instinct: survey, synthesis and philosophical...

2. Tierpsychol., 50,364-386 (1979) @ 1979 Verlag Paul Parey, Berlin und Hamburg ISSN 0044-3573 / ASTM-Coden: ZETIAG

Department of Philosophy, State University of New York at Albany, New York

Half a Century on the Concepts of Innateness and Instinct:

Survey, Synthesis and Philosophical Implications

By JOHN CASSIDY

Received: May 5 , 1978

Accepted: May 21, 1979

Abstract

This paper first surveys and criticizes the various attempts by students of behavior t o define the concept of innateness. A new definition, based on these (especially tha t of LORENZ), and reformulable in terms of now classic not’ions in genetics and evolutionary theory, is then offered: A trait is innate if, and only if, i t is canal.ized and such that any phenotype in the reaction norm which does not possess the trait is a morphose - hence m a h d a p t e d - and such that all modifications do possess the trait. A narrower definition of innateness, based on the first definition, is suggested t o delimit what is called “the Lorenzian notions of innateness” and t o provide a framework within which to ,discuss the notion of a fixed action pattern. Evidence, from the recent literature, is adduced to show the existence and importance of such patterns - even for human behavior. In the final section, it is argued that a paradigm shift has indeed occurred and that although th.is scientific revolut.ion has been accompanied by many of the irrational elements noted b y the Kuhnian school of philosophy of science, the shift has in fact been made upon perfectly rational grounds. That this should be t rue of so controversial a field is strong evidence against the irrationalist thesis in philosophy of science.

Introduction

The instinct controversy has not, heretofore, much engaged the attentions of philosophers, although much of the scientific writings have in fact been philosophy of science: questions of logic, the scientific method and even Kantian synthetic a prioris have been much discussed. One of the most in- fluential papers (LEHRMAN 1970) is concerned with “Semantic and conceptual issues in the nature-nurture prcblem”; another ( JENSEN 1961) takes its basis from the philosophical position of operationalism. Certainly, some basic sort- ing out of issues is needed.

The controversy is, of course, of great interest for its own sake, and not merely for the “philosophical” issues already mentioned. It bears on the issue of the genetic determination (if any) of behavior and so on important issues

Half a Century on the Concepts of Innateness and Instinct 365

in ethics and social philosophy and policy. This last has, in fact, been one of the major stumbling blocks in the way of a resolution: some think Ethology and Sociobiology support, and are derived from, right wing capitalism (e.g., KALIKOW 1976 and SAHLINS 1976), or are mere prophecies of doom (e.g., SCHNEIRLA 1966); too many of LORENZ’S opponents seem to some to echo the facile optimism in social progress of the 19th century.

This paper has four related goals: 1. Briefly to trace the recent intertwining histories of the concepts of

innuteness and instinct, and to try to explain why the controversy has remained so heated despite a growing agreement on the science involved.

2. To isolate a primary definition cf the innate, and a spectrum of stronger secondary definitions, to which there is widespread - if sometimes tacit - agreement.

3. To define a noticn of a Fixed Action Pattern (hereafter, FAP) especially with respect to those characteristics (such as spontaneity, central control in the CNS, etc.) most in dispute.

4. To sort out the confusions present in some of the best theoretical papers on these concepts (such as LEHRMAN 1970 and LORENZ 1967) as well as those in the writings of authors who cite the former.

That such confusion exists may be puzzling, but is certainly demonstrable. For example, as we shall see, LEHRMAN (1970) offers one definition of the innate which is vacuous (i.e., such that nothing is innate), yet which is cited with approval by BEER (1975) and by BROWN (1975, p. 36) as though LEHR- MAN had been offering a definition in terms of Lorenzian deprivation experiments. Again, LEHRMAN (1970), who is arguing against LORENZ (1967), is cited by SVENDSEN (1974, p. 768) as being on the whole in favor of the genetic control of behavior. It is also distressingly common to find that no notion of the innate is permitted except the geneticist’s notion of heritability (e.g., LEHRMAN 1970, JENSEN 1961), which we shall see is a perfectly distinct concept from the one that, for example, LORENZ has in mind.

We will begin with a brief account of the recent history of the innateness- instinct controversy and an attempt to set out some of the issues involved. Then we will turn first to the concept of the innate, with special references to LEHRMAN (1970) and LORENZ (1967), since the theoretical arguments ended with these two much-cited papers (although relevant scientific work has since been done), and second to the FAP controversy proper. Finally, we will try to estimate the change which has really occurred in our beliefs concerning animal behavior, and the reasons for the vehement, and continuing, controversy about the genetic control of behavior.

The Issues

The instinct controversy in this century has largely revolved around two points: is there a reasonable sense of “the innate” in which some behavior, including “instinctual behavior”, will be called innate? And, what is the proper interpretation of the Fixed Action Pattern? The century opened with criticisms of instinct theory as being vitalist and teleological (e.g., Kuo 1924, 1930, 1933, and cf. DIAMOND 1974); some philosophers have continued the dispute in these terms (eg., WILM 1925), and a few recent polemics (e.g., JOFFE 1973) have revived this complaint. However, LORENZ and his immediate predeces- sors (WHITMAN, HEINROTH, CRAIG) were never vitalists, and LORENZ has often

366 JOHN CASSIDV

criticized vitalism (LORENZ 1942). Indeed LORENZ, always the mechanist, a t first attempted to explain instincts in terms of Sherringtonian Reflex theory (LORENZ 1970, pp. xvii.). The “instinctual” interpretation of the FAP, with which the contemporary dispute deals - however much that interpretation has changed during 40 years of research by LORENZ, his colleagues, and his opponents - first appears in propria persona only in 1938 (LORENZ 1938; LORENZ 1970, p. xx), and it is with this version of the instinct theory and its modifications that we shall be concerned.

Much of the innateness controversy centers around the question: to what extent is behavior genetically determined? And to just what does “genetic determination” amount? A variety of meanings has been given to the terms involved, and much of the controversy has been generated by one contro- versialist attributing a mistaken meaning to another’s terms. However, the two opposing camps can be separated quite simply: one camp prefers to dwell on the developmental plasticity of the individual animal, and the other on the rigidity and adaptedness of an animal’s behavior. The camps can also be characterized in terms of research interests (cf. LEHRMAN 1970): one is interested in ontogeny, the other in phylogeny; and although any such strict dichotomy is an overstatement (few have raised as many animals as LORENZ), we shall find it helpful in considering some of the opposing points of view. It is clear that if one is interested primarily in the development of behavior, questions concerning the precise environmental factors necessary to normal development will be very important, whereas if one is interested in the evolution of behavior such environmental factors may often be uninteresting. This difference between the two camps has led, particularly in morally or politic- ally sensitive areas, to much heat: SCHNEIRLA (1966), for example, accuses LORENZ of burdening man with a sort of biological original sin when LORENZ contends that man is innately aggressive. For SCHNEIRLA, interested in developmental plasticity, the scientific foolishness of LORENZ’S claim only heightens its moral unacceptability.

These two camps are again in opposition when it comes to the interpretation of FAPs. A FAP is acceptable to both camps if described as follows: a FAP is a highly stereotyped, species-specific behavior pattern, differing from a reflex in that a FAP, while “set-off” in reflex-like manner, is not necessarily directed by external stimuli, and in that a FAP has a spontaneous character: i.e., an animal seeks situations which will release the FAP. (It was this last characteristic above all which led LORENZ to abandon his original reflex interpretation of the FAP [LORENZ 1938, 1970, pp. xvii].) This much is generally, although not perhaps universally (Kuo and J. BROWN may be exceptions), agreed to. In addition, there is general agreement (cf. MOLTZ 1965) that the FAP is inherited and is as valuable a tool for distinguishing species as are morphological characteristics. However, the following additional characteristics, advanced by LORENZ, seem to render the FAP unacceptable to the environmentalist, or empiricist, camp: the FAP is “innate”; it is not (at least, adaptively) modifiable during ontogeny (outside of a certain sharpening due to learning); it is centrally controlled by the CNS; it is explicable only with the aid of a supposition of endogenous neural activity (or something like this) and not merely in terms of other motivational systems (particularly only those of physiological need for such things as food and drink).

What is a t issue here really amounts to two quite different paradigms for animal behavior. If one accepts the “Lorenzian additions”, then animals are active (not merely re-active); their personal goals (i.e., those results attained


by their activities) are not necessarily those directly contributing to their survival, such as food and drink, but may include activities (such as territorial defense, hierarchy-fighting) only indirectly contributing to their survival; and, finally, these activities are not eradicable by training, but can only be more or less repressed or modified. An example commonly cited (LEYHAUSEN 1965) is that of the cat, whcse desire to hunt is stronger than its desire to kill, and whose desire to kill is stronger than its desire to cat (where desire and its strength can be defined, if one wishes, as it is in fact determined: for example, by frequency of performance in situations freely permitting any of the three behavior patterns). In addition, species may well be radically different in their behavioral potentialities, due to differences in genetic potential specific- ally concerning behavior (and not simply concerning morphology).

The contrasting system of belief, or paradigm, in which the FAP is not innate, there is no behaviorally important endogenous neural activity [except for circadian rhythms (MOLTZ 1965; J. BROWN, pers. comm.)], and the FAP is not centrally controlled, is that of Comparative Psychology (as described by, say, LOCKARU 1971). In this system, animals act as they d o primarily because of their morphological characteristics [cats hunt because they are physically suited to hunting, not because of some “innate urge” (KUO 1924, 1930, 1933, 1970)], and because of the contingencies of reinforcement (SKIN- NER 1974, chap. 3). The true goals of animals are the obvious physiological ones. Goals subsidiary to these (hunting, killing, territorial defense, hierarchy fighting) arise only because of their effectiveness in achieving the true goals, and are eliminable by appropriate rearing 2nd training. In addition, then, all animals are, behaviorally considered, essentially the same (e.g., LOCKARD 1971). Few, perhaps, today completely adhere to this latter paradigm (perhaps Kuo and SKINNER do), but it does seem to characterize a tendency on the part of those (such as SCHNEIRLA and LEHRMAN) who, although they might disagree with this paradigm at various points, nonetheless follow its implications when discussing human behavior.

The question of the FAP seems to dominate - be the cash of - the innateness-instinct controversy, as can be seen by the preceding clash of two paradigms. It is seen as a clash between learninghnstinct or, at least, modi- fiability/rigidity. We shall see reasons below for modifying this view. Not all that is innate is a FAP [I will refer not only to IRMs (innate releasing mechanisms) and reflexes], nor is a FAP always devoid of learning. However, this opposition of naive positions is explicative of the controversy. We turn now to the controversy about innateness.

The Innate

We will begin with an exposition of LORENZ’S (1967) views on the innate, turn to LEHRMAN’S (1970) criticisms of LORENZ and his own proposals, return to LORENZ for a deeper criticism of his definitions, and then finally we will attempt a definition of the innate based on what we have learned from LORENZ and LEHRMAN, and incorporating some concepts from evolutionary genetics.

LORENZ (1967) bases the analysis of the innate upon two concepts: that of phylogenetic adaptation (vs. adaptive modification) and that of the provenance of the information underlying an adaptation. These two concepts are not, as might seem at first, independent. Phylogenetic adaptations can only be distinguished from adaptive modifications by discovering whence came the knowledge underlying the trait in question: the genome or individual acquisi-

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tion (“learning”) (LORENZ 1967, pp. 9-10, 25, 103). And the only certain test seems to be a deprivation experiment, i.e., an experiment in which an individual is deprived of some experience (particularly social experience) and it is then seen whether or not the individual still performs the behavior in question. If it does, then the act is innate; if i t does not, then we cannot con- clude that the act is not (at least in some of its parts) innate, since the deprivation experiment may not merely have withheld information, but also perturbed the individual in other ways (LORENZ 1967, pp. 85ff). Thus i t is often very difficult to determine that such and such a trait is innate (LORENZ 1967, p. 25). Of course, a “failed” deprivation experiment may sometimes suggest a new one which does succeed.

Although LORENZ’S definitions are in terms of an information metaphor, it is clear that his actual intuition about the innate is based equally upon not only the provenance of information but also upon the evolution of adaptive behavior. LORENZ’S basic intuition about the innate is probably that it is what has evolved, what has been selected for because it was adaptive (cf., e.g., LORENZ 1967, .pp. 32 f, 106), whence, indeed, the emphasis on phylogenetic adaptation. HIS reasons for choosing to avoid this as a primary account - and, as W. M. SCHLEIDT informs me, for his extensive consultation with experts in information theory - seem to mc to be two: first, a definition via information permits a simple justification of the deprivation experiment (LORENZ 1967, chap. 7); and, second, may permit an easier defense against the claim made by his opponents (e.g., LEHRMAN 1970; JENSEN 1961; BEACH 1955) that he can only define the innate as the not-learned (LORENZ 1967, p. 103). [Amusingly, MAIER and SCHNEIRLA (1935, pp. 270 f) do accept this definition of the innate, although they hope ultimately to be able to offer a definition independent of the notion of learning.]

Although LORENZ has much else of interest to say about the innate, we have analyzed enough to turn now to LEHRMAN’S critique. After that we shall return to LORENZ’S theory and criticize certain points, particularly the information metaphor and the strength of his definition of the innate.

LEHRMAN’S paper (1970) is chiefly concerned with two things: first to point out that much of the difference between LORENZ and himself is one of interests rather than science; and, second, to offer two definitions of the innate which will demonstrate this.

LEHRMAN is primarily interested in the development of behavior, he says, and LORENZ in the evolution of adaptive behavior (LEHRMAN 1970, pp. 18f, 28, 31, 35, 37, 45-48). This is probably true. However, according to LEHR- MAN (1970, p. 24), LORENZ has confused the two and tends to use the term “innate” ambiguously, thus committing the sin of equivocation. LEHRMAN himself is not quite free from a similar confusion, when he asserts (pp. 28-30) that any experiment which produces no change in behavior is a failure in that it gives us no information. Passing over his comment that this is a fundamental question of logic and the experimental method (which i t clearly is not), one simply notes that where an environmental influence is expected to produce a change and a deprivation experiment shows it does not, we have surely learned something important. But let us turn tc his two definitions of the innate.

LEHRMAN specifies two definitions of the innate: the first is what he calls the geneticist’s notion of the heritable (or inherited or hereditary) (p. 22), namely, that a trait is innate or heritable if, and only if, the distribution of the trait in an offspring population is predictable given the distribution in the parent population and the mating patterns in the population. For the predic- tion to be possible, however, we need also to know the genetics underlying the

Half a Century on the Concepts of Innateness and Instinct 3 69

trait; further, his explication of this notion includes the claim that variation in such traits is due solely to genetic variation - a rare trait indeed (see below). The second definition of the innate is developmentally f ixed, indeed so developmentally fixed that the trait will develop in an individual “regard- less of the environment in which it is reared” (p. 23) due to the strength of the influence of the genes.

The geneticist’s notion of heritability is not what LEHRMAN means by his first definition. We now have two genetical notions of heritability (e.g., FALCONER 1960, or MCLEARN and DEFRIES 1973). In the broad sense, it means the proportion of phenotypic variance ‘due to’ genetical variation (VG/Vp) with respect to a specified population and environment. In the narrow sense it means the ratio of additive genetic variance to phenotypic variance. These definitions, however, are not really suitable as a means of defining the innate in this context. Note, for example, that neither definition gives us a measure of the genetic determination of a trait in any very interesting sense, since so long as the environment is the same for each individual in the population, the heritability in the broad sense will be 1, since whatever phenotypic variance - if any - is observed will be due to genetic rather than environmental variance (yet the actual presence of the trait could be largely due to the environmental factors)! The notion is clearly not what is needed here, where we are trying to characterize such things as the “instinctive” reaction of a male stickleback to “red-below”, and indeed where the traits which we want to call innate will probably have a l ow heritability, the variation in the trait quite likely being due to environmental factors (or, at least, non-additive genetic variance: cf., MCLEARN and DEFRIES 1973, pp. 253 ff). However, this geneticist’s notion seems to have led a number of people astray.

A familiarity with this notion of heritability seems to be at the bottom of much of the talk that only differences can be said to be innate, or heritable, or that we can only say that such and such differences are due to genetic differences. Those who have argued for this include BROWN (1975), LEHRMAN (1953, 1970), JENSEN (1961), BEACH (1955), SPURWAY (1953), HINDE and TIN- BERGEN (1958), and DILGER (1962). These authors tend to rest their case on the ground that geneticists only talk of “differences” and that behavior students should follow suit. Geneticists talk mostly about differences - that is, phenotypic and genotypic variance - for, I think, two reasons: first, because i t is genotypic variance (and its contribution to phenotypic variance) which is the prerequisite for evolution, and experiments to answer questions surrounding selection have been a focal point of genetic research; and, second, research into genetic diseases and the contribution of the genes to intelligence, success and so forth is research into differences. Not until recently have geneticists become interested in the species-typical (THEISSEN 1972).

What does i t mean to say only differences can be said to be innate? The geneticists’ answer is not always that given by these authors. JENSEN (1961) gives something like the geneticists’ answer: all we can talk about is the contribution of genetic differences to phenotypic differences relative to such and such an environment and population (although, curiously, JENSEN seems to limit experimentation to cases in which the environment is the same for each individual in the population). DILGER (1962), in contrast, feels quite com- fortable in talking about how rigidly the genetic constitution of the individual controls ontogeny (p. 38), and how there is more genetic control involved in not-learned behavior (pp. 36 ff). HINDE and TINBERGEN (1958) accept the formulation, but when they come to give an analysis and example (p. 34), they demonstrate no difference between their formulation and one not men-

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370 J O H N CASSIDY

tioning differences at all. Two experiments show that the use of feet in feed- ing is hereditary in tits but not in chaffinches; each experiment can stand on its own, and hence no talk of differences is needed.

Having seen why LEHRMAN has not used the (real) geneticist’s notion of heritability [and disposed of the differences argument, to which LEHRMAN himself has an unfortunate tendency to hark back (pp. 22, 25 f, 38)], let us look more closely at his two definitions of innate or inherited.

One can sympathize with LEHRMAN’S aim in giving these two definitions. The definition which LEHRMAN calls the geneticist’s notion of the innate is intended to satisfy LORENZ, who has always been primarily interested in the evolution of behavior: this definition fits into an evolutionary framework very well (LEHRMAN 1970, pp. 22 f). The developmental fixity definition is intended to be of use for those interested primarily in the development of behavior. And he wants to claim that the two definitions exist in “different, not parallel” dimensions (LEHRMAN 1970, p. 23). LEHRMAN’S account is open to two substantial criticisms.

First, it is simply not true that the two concepts exist in “different not parallel” dimensions. Anything which is developmentally fixed due to the influence of the genes is surely (at the very least in principle) heritable. Hence, malgri. LEHRMAN (p. 24), LORENZ is not necessarily confusing these two concepts when he introduces as evidence of innateness both heritability and the lack of learning influence, since both, for example, are evidence of developmental fixity (both are eaually necessary conditions of this fixity).

There is a more serious criticism of LEHRMAN’S distinctions. The notion of developmental fixity is too strict: nothing fits it, as we noticed earlier on. The notion of heritability, as given, is tco weak: what is needed, if possible, is a concept helpful in understanding the behavior and phylogeny of animals in nature, not merely fruitflies in laboratcries. A trait which is heritable in environment X is one which indeed is open to natural selection in X (LEHR- MAN 1970, pp. 22-23, 28), but the members of a species must survive in a variety of environments, and the species evclved in a variety of environments. That is, the trait, to be called innate, must, at least, be heritable (in LEHRMAN’S sense) in a reasonable variety of environments: which is as much as to say that it must have a reasonable degree of developmental fixity. So we are back to a notion of the innate which includes both heritability and some degree of developmental fixity: and we still have the problem of what kind of and how much of developmental fixity. LORENZ’S distinction between the provenance of information is one solution, since i f the information underlying a certain trait is contained in the genome, then the trait is impervious to a certain (in- tcresting) class of environmental changes.

Let us return now to LORENZ’S account of the innate and try, in the course of criticizing it, to arrive a t a more adequate definition.

LORENZ’S notion of the innate is at once developmental in that an innate trait is tested for by a deprivation experiment and must be relatively impervious to environmental perturbation during ontogeny; evolutionary in that an innate trait must be a phylogenetic adaptation, and genetic in that an innate trait must be heritable in LEHRMAN’S sense, and must have evolved out of characteristics which were sufficiently highly heritable in the narrow sense. I think that LORENZ is correct i n thinking that any useful notion of the innate must involve these three aspects.

However, I find three related difficulties with LORENZ’S account: first, although knowledge about information can be an important indicator of innateness, I do not think that information is the basic concept involved; and,


second, as a result of this, a reliance upon a definition based upon the provenance of information leads to a misleading - and, I shall argue, ultimately unclear - classification of behavior. Further, I am not sure that such a definition permits us properly to interpret the result of deprivation experiments. Let me try to justify these three claims.

The information account of the genes is tempting. The effects of the genes in such and such a series of environments look like the objects people produce on the basis of a set of instructions, a blueprint: thus we have the animal as machine, the effects of whose genes are adaptive and complex. SO long as the environment is within a fairly wide range of possible environments, the genes are able to produce the normal adult organism; without the genes, nothing of the sort would happen. Thus we can readily think of the genes as having the information necessary to the production of a complex organism/machine. Now among the things produced in this organism are methods for the machine itself gaining information (i.e., altering itself adaptively on the basis of a changing environment): learning structures. That is, in some cases it is “prudent” for the genes to build in methods for the machine to modify itself adaptively in the presence of different environments. This adaptive modification may be of two sorts: in the one many different modi- lications would be equally adaptive depending upon the environment; in the other only one modification can be adaptive, although maladaptive modifications are possible. These latter may include not only marginal (in the sense that these cases are at the far end of the lability and insight spectrum of learning) forms of learning [such as imprinting, certain cases of the learning of a releaser for a FAP (SCHLEIDT 1962; HAILMAN 1970; and see belowfl, but also clearer cases: for example, a bird’s learning its species’ song (in those cases where the bird is able to learn those of other species). In such cases the genes engineer the presence of the appropriate environmental stimuli (cf. MAYR 1970, chap. 6): the mother of a bird which relies on imprinting is generally present during hatching; birds which must learn their songs are raised by their parents; rhesus monkeys are raised in rhesus monkey societies; when it is adaptive to have a FAP much of it may be “given” to an individual without the necessity of learning, so that the individual need only “fill in the gaps”. In these instances of the second sort of modification, the individual is indeed “developmentally plastic”, but not in an interesting way, for only one fixed result can be adaptive.

Causally considered, then, we seem to have three broad types of phenotypic traits: (1) those for which we can test by suitable deprivation experiments, whose manifestation depends upon the environment only for materials, which do not depend upon learning structures (which are themselves usually members of this category), (2) those which depend upon an adaptive modification in response to the environment, and which are such that different environments give rise to different, but equally adaptive, traits, and (3) those which depend upon an adaptive modification in response to the environment, but where the modification is the only adaptive one, and in which the environment is itself a result of selection in the species (i.e., the individuals in the species have been selected to provide such an environment for themselves and/or for their offspring). Note that these traits which have been selected for in order to provide the appropriate environment may, for their manifestation, depend upon learning in this second sense: a bird imprinted upon an inappropriate object may not be able to provide the correct environment for its offspring (if any) (cf. LEYHAUSEN 1967, pp. 296ff). The first of these broad types corresponds to LORENZ’S innate, and the second two to his learned.

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There are, however and alas, some problems with this apparently nice trichotomy. First, I do not think that ( I ) is adequately characterized, nor do I believe that deprivation experiments succeed in distinguishing it completely from (3). Certain classes of cases are clear enough: where imprinting, or some other form of learning is involved; but who can say that no sort of learning is involved in even the manifestation of so obviously a sort of innate behavior as the aggressive behavior of the male stickleback? What the deprivation experiment shows is that no learning of a particular, and interesting, sort is involved. Second, when we come to a case such as that of the female rat who, if prevented from access to its own genitals (so that it cannot lick them), turns into an unsatisfactory mother (although other sorts of deprivation experiments leave its motherly behavior intact), or of female rats who, if prevented from playing with “building materials” in ycuth turn out to be incapable of building nests [ behavior unaffected by other deprivation experiments - in fact the relevant deprivation may have been of a suitable nest-building site (THORPE 1956); LORENZ 1967, pp. 64 f , notes that EIBL-EIBESFELDT (1970) was unable to confirm the results of the original experiment], when we come to such cases, it is difficult to know whether i t is a case of (1) or (3). The problem, in part, is that it is not now possible precisely to characterize the notion of a “learning structure” [and so to distinguish learning from uther sorts of environmental influences: hence the imprecision of “materials” in the formulation of (I)] (LORENZ 1967, pp. 10 f), and this creates problems even though we (including LORENZ) do not want to make a dichotomy between innate and learned. This is as much as to say that because it is difficult, a t least as yet, to identify this environmental stimulus as information, and thut as a non-informational environmental stimulus, the trichotomy is unclear. And this means that it is difficult t o evaluate a deprivation experiment, since in order to decide if a deprivation experiment shows anything of interest about innateness, we must first know if the stimulus of which the organism is being deprived counts as information, or not. But we do make such evaluations, and frequently (cf. LORENZ 1967). Sometimes, I agree, such evaluations are based upon an intuitive feeling for what stimuli count as infcrmational. But in the problem cases I mentioned above our intuitions boggle. Where then do we turn? Can we find a definition of the innate which can both justify the information analysis (as far as it goes) and provide us with a guide to these difficult cases? I will first offer a quite broad definition of the innate, which conflates classifications ( I ) and (3) above, and then intrcduce ways of narrowing that definition.

Drawing upon our analyses of LORENZ and LEHRMAN we want, in general, to say that a trait is innate in a species if, and only if,

1. The trait is an adaptation and has evolved from traits sufficiently highly heritable in the narrow sense.

2 . The trait will develop in an individual of the species so long as [a) the individual is statistically physiologically normal (this clause is only to exclude obvious cases of mutants, etc.) and (b) the individual develops in one of the environments in the natiual runge of environments (see below for definition).

3. If the trait does not develop in the individual, the animal is seriously maladapted to its natural environment (where “maladapted” includes the inability to reproduce as a maladaptation).

4. By “natural range of environments” we mean not the statistically normal range of current environments of the species but of the (past) environments in which the trait and the individuals possessing the trait were selected for, and would not have been selected for otherwise.

Half a Cen tu ry on the Concepts of Innateness and Instinct 3 73

[Determining the past environment of a species is, of course, a somewhat difficult task. In addition, it sometimes seems that our best evidence for a correct judgment about past environment is our belief that such and such a trait is innate! - a method of inference which would seem to render my definition circular (a possibility suggested to me by W. M. SCHLEIDT). However, things in fact are not so bad. First, the evolutionarily important aspects of the past environment - climate, geography, predators (and as much of their behavior as can be inferred from paleontological evidence), competitors, etc. - can often be determined without recourse to innateness. Second, deprivation experiments can give us good evidence for innateness, which can then be used to infer statements about past environment. Third, the current environment (and that of the past few, or more, generations) can often be reasonably claim- ed to be similar to the past environment. And so forth. The logical point is that circularity between A and B can be avoided - even when the determination that a is an A is relevant to the determination that b is a B, and vice versa - so long as there can be independent evidence both that a is an A and b is a B. And this is clearly the case with innateness and past environment. Interdependence need not entail circularity.]

It is important to notice that the natural environment in this sense may include behavior which was innate (by this definition) in the ancestral population and probably is innate in the present species (cf., e.g. WADDINGTON 1959). The two innate behaviors may even, in the present species, be mutually dependent for their manifestations. For example, the ability to be imprinted could not have been selected for until some degree of sociality had already evolved in the ancestral population. A natural environment for an imprintable species thus includes some degree of sociality (itself inevitably an innate trait). And the continuance of that sociality now depends upon successful imprinting. It is illuminating here to mention a case analyzed by EVANS (1973): he describes two allied but distinct species of gulls such that the naive young of one species (herring gulls) prefer t o follow the calls of the adults of the other species (ring-billed gulls). The specificity of the call and response have declined (presumably by mere drift) in herring gulls simply because these birds are strongly territorial, so that a large amount of territory is defended, and the ycung remain within it for quite some time. Ring-billed gulls, on the other hand, defend much smaller territories, and the entire family may move only a few days after hatching. Here again we have a case of evolved behavior affecting evolved behavior.

The general point that the genotype engineers the environment necessary to its proper expression is also made by, for example, MAYR (1970, chap. lo), and is involved in the notions of normalizing and canalizing selection (cf. DOBZHANSKY 1970, chap. 4; WADDINGTON 1941, 1960a).

This definition of innateness is broader than LORENZ’S in that (1) The natural environment may well be a social one, and so those aspects of the social environment upon which “the genes were counting” (because it was in this social environment that they were selected for, and would not have been selected for otherwise), and which a deprivation experiment would eliminate, are permissible developmental factors; and ( 2 ) the characteristic, although developmentally canalized (see below), may depend for its manifestation upon a certain class of individual adaptations (including “classical” learning). Further, it is evident that the ontogeny of such a trait may be more complex than permitted under LORENZ’S definition. This definition also seems to have two cardinal virtues. First, it permits us to call innate certain characteristics

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which LORENZ’S strict definition would exclude and yet which I think we would like to call innate (for example, those which I mentioned as problem cases for LORENZ’S definition). Secondly i t is based upon fundamental biological notions (such as adaptation, selection, etc. - and see below) rather than upon concepts brought in from outside of biology (information theory). Furthermore, the definition explains the allure of the information analysis and largely justifies its use in our analyses of behavior. And thus it also explains and justifies the use of deprivation experiments - still our most important tool for deciding about innateness - and provides us with a criterion for deciding when such and such a deprivation experiment is good (i.e. reveals innateness or not). A good deprivation experiment (in this sense of good) does not deprive an animal of stimuli present in the natural range of environments. Other deprivation experiments, of course, will be useful in understanding ontogeny and the way that behavior is put together, but we need not take them as showing anything important about innateness per se. Finally, I would tentatively suggest that this definition provides a better framework for the study and analysis of innate learning structures, i.e. the ways in which learning, and its objects, are themselves, to varying degrees, genetically programmed as a result of natural selection. And this study, as an anonymous referee pointed out to me (and as our problem cases of innateness and other cases, such as bird song “learning”, have indicated), has been of increasing importance as we have learned more about animal behavior. Here too deprivation experiments can be of great importance, since they can reveal the presence of “programmed learning”, i.e. special, limited, rather precisely evolutionarily designed learning structures.

By slightly extending WADDINGTON’S notion of canalization (in a way he would apparently find acceptable: WADDINGTON 1959, 1960 b) and using the notion of reaction norm, with its attendant terms “modification” and “morphose”, we can produce a more succinct primary definition of the innate, and introduce methods of strengthening it.

A canalized trait is one whose manifestation i s relatively insensitive to changes in either the genetic or the “outside” environment. Canalization can be selected for (WADDINGTON 1960 a; WADDINGTON and ROBERTSON 1966) and presumably has been for those traits we call innate. Of course, a canalized trait is not insensitive to any change in the environment, but rather will develop in that range of environments natural, in the sense earlier defined, to the individual. Let us include those aspects of the social environment which are natural in this sense, and indeed any aspects of the environment which the members of the population engineer by behavior which has been selected for (and so was probably- innate in an ancestral population before the emergence of the behavioral trait originally in question) such as certain aspects of the environment which the population chooses (cf. WADDINGTON, WOOLP and PERRY 1954; WADDINGTON 1959).

The reaction norm of a genotype is the range of phenotypes which are producible by varying the environment. By and large, those phenotypes which develop in wild species, in response to environmental stimuli that recur regularly in the habitats of these species, are adaptive. Responses to unusual or artificially created environments are often maladaptive. The first were called modifications, and the latter morphoses, by SCHMALHAUSEN (DOB- ZHANSKY 1970, p. 37).

We can now succinctly characterize an innate trait as one which is canalized and which is such that any phenotype in the reaction norm which does not possess the trait is a morphose (hence maladapted), and such that all modi-

Half a Century on the Concepts of Innatcncss and Instinct 3 75

fications do possess the trait. [This definition is slightly oversimplified, since it is possible for two traits to be both mutually exclusive and innate (in this sense) if a common environmental stress can shift the development from one adaptive canalized path to ancther. Furthermore, some species may be poly- typic in that there are two, or more, common genotypes each adaptively reacting differently to a common environmental influence. J

In order to strengthen this definition of the innate in the direction of Lorenzian innateness, we have only to include alterations in the natural environment which (as, for example, a deprivation experiment could show) leave the trait canalized. In particular, and A la LORENZ, we can specify that such and such a learning situation is not necessary to the natural development of the trait. We can rarely, if ever, be quite sure that no learning of any sort is necessary for the normal development of the trait, but it seems that some traits - particularly of FAPs - are innate in stronger, and interesting, senses than that according to our primary definition. It is important to note that any secondary, stronger, definition of the innate requires an explicit characteriza- tion of those aspects of the normal environment whose alteration does not affect the development of the trait in question. We may refer to these secondary senses of innateness (as a body) as the Lorenzian sense of innateness. We turn now to FAPs.

Instincts and the Interpretation of the FAP

When first discovered, the FAP seemed to be well-described by LORENZ’S hydraulic (or “flush toilet”) model. In this model, we have a reservoir slowly filling up, a spring-held outlet valve, and release mechanism which can pull out the valve. As the reservoir fills, the animal performs appetitive behavior; upon sighting the releaser, the valve is pulled and the water shoots out (the FAP is performed). If the releaser is nct sighted for a long time, the increasing pressure exerted by the reservoir upon the spring may cause the valve to be forced open anyway (“vacuum activity”), or, at least, be pulled by only a slight pressure, i.e., the FAP will be released by a less perfectly appropriate releaser, one which would not have worked earlier on. The distance the water shoots out corresponds to the intensity with which the FAP is performed (including only partial performances). This model has had to he modified as new discoveries about the FAP have been made; to some of these we now turn.

The original analysis of the FAP has had to be modified chiefly in two points: first, upon the discovery that learning of some sort is often involved (particularly with respect to the releasers, and a sharpening of the performance of the FAP), and, second, upon the realization that it is not always the performance of the FAP which is the sole consummation (as was believed a t first), but also sometimes, at least in part, the perception of the result of the performance of the FAP. As an examination of a couple of the classes of examples will show, these modifications of the original picture are not as serious as some authors have seemed to suppose. Indeed, LORENZ’S hydraulic model has not, I think, entirely lcst its value (cf., e.g., LEYHAUSEN 1965, for a vigorous defense).

(1) The releasers are sometimes “learnt”. This is notorious in cases where the releasers for a FAP depend upon imprinting. Again, the male stickleback (in the appropriate sexual state) defends his tevritory by means of an aggressive FAP against red-below objects. No learning enters into “red-belowness” as a releaser; but the animal must have “learnt” that this particular piece of

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water is its territory. I have put learnt in scare quotes because the sense of learning involved here is clearly neither a “learning that” nor a “learning how”: we are evidently dealing with a sense of learning quite different. Animals “grow accustomed to, and adopt” a territory; an individual who is imprinted does not learn how to do scmething, nor can it, un-metaphorically, be said to learn that such and such is the appropriate target of its behavior: it only ‘acquires’ a sort of object as a target. Because it can easily seem to the observer that the animal has learned that this is its territory (and so it ought to defend it) and that this is its mother (and so it ought to follow it), this distinction between this sort of learning and learning-that (i.e. the mere acqui- sition of information), has not always been perceived. This sort of learning is perhaps closer to that involved when we say, “he was brought up to abhor theft and believe in God”.

(2) Often, perhaps usually, the releaser of a FAP, even if innate in LORENZ’S sense, is capable of refinement, so that the individual performs its FAP only upon “more appropriate” targets (LORENZ 1967, p. 35).

(3) A FAP may sometimes be a complex of taxis, learned and innate (in the strong sense) movements, learning serving to mold these elements into a whole (cf. LORENZ 1967, pp. 64f and 81 f). They can also exist alongside learned behavior which supplants them in some cases (LEYIIAUSEN 1965).

(4) It was originally thought that the mere performance of the FAP was the satisfaction involved; it is now realized that the perception of the result of that activity, if appropriate, may be a t least part of the consummation. Similarly, it is now thought that this result can serve as a reinforcement of the behavior [thus molding a FAP into perfect form, as we described in (3)], and that without this successful effect the frequency of the performance of the FAP is sometimes lessened (SCOTT 1962; CLARK 1962; LORENZ 1967, pp. 64f and 81).

The addition of a certain plasticity to the concept of the FAP which is introduced by these four points is not spurious, in that many of these are ways of modifying behavior to make it more adaptive, not simply ways which disrupt the animal, yet these points really serve to emphasize the rigidity of the FAP. For the possible ways of modification are limited. Furthermore, most of these possibilities have clearly “been planned for”, are perfectly adaptive and, in particular, have been adapted to increasing the value of the FAP, and the frequency with which i t occurs with successful result. The learning which is involved has been “planned for” in the sense we specified in defining innateness.

Thus far we have considered matters about which there is widespread agreement (e.g., MOLTZ 1965), researchers chiefly being distinguished by the aspects of the FAP which they find interesting (as we saw in our discussion of innateness). On the basis of these agreeable matters and the results of certain physiological experiments (particularly those of VON HOLST 1937, 1939), LORENZ and his co-workers have made inferences about the FAP which have been violently criticized (e.g., LEHRMAN 1953; MOLTZ 1965). These controversies center chiefly around the following points: innateness, the explanation of the stereotypy, the role of learning (and other experience), presence of specialized neural structures underlying each FAP, and endogenous neural behavior (or some other explanation for the spontaneity of FAPs). These controversies arise out of two different “theoretical interpretations” of the FAP. On the one hand, we have LORENZ arguing for ‘genetic encoding’, special neural structures, endogenous neural activity, and the relative uninteresting-


ness of the influence of learning (and other experience). O n the other hand, we have LEHRMAN, MOLTZ, SCHNEIRLA and company arguing for “alternative rcutes to stereotypy”, a single set of developmental laws capable of encom- passing acquired responses and FAPs (MOLTZ 1965, p. 36, but cp. p. 40), motivational systems not involving endogenous neural activity, and the importance of experience (i.e., all environmental influences) in the development of a FAP. We will first discuss each of these issues, and then turn to their broader importance as ingredients in two different paradigms.

Some of the disagreements mentioned abcve are largely verbal, or merely frivolous. We have already analyzed senses in which a FAP can reasonably be said to be innate or genetically encoded. Since a FAP differs from learning and reflex (but see below for the fuzzy boundary between reflex and FAP), we may reasonably suppose that it is based on peculiar (but cf. LEYHAUSEN 1965) and innate neural structures. MOLTZ’S (1965) suggestion, citing the work of DAVIS (1957) on towhees, that “anatomical and functional properties of peripheral structures also provide a possible explanation of behavioral stereotypy” cannot be of much general importance (even though we certainly expect evolved morphology to go hand in hand with evolved behavior) since most FAPs involve the use of limbs and muscles used in the making of other movements. More crucially, this suggestion does not account for the observed spontaneity of FAPs.

The two questions which have been most in dispute are: (I) Is the FAP centrally controlled by special neural structures? and ( 2 ) What is the explanation of the spontaneity of FAPs?

(1) The physiological evidence for the central control of ‘FAPs is primarily of two sorts. First, from experiments involving deafferented limbs, and, second, those involving so-called punctate electrical stimulation (actually, a small field is produced) of the brain. MOLTZ (1965, p. 33) complains that the deafferentation experiments deal with such simple phenomena as respiration and heart beat and concludes that it is quite a leap from these to FAPs. How- ever, BULLOCK (1961) already contains an able discussion of the central coordination of behavior nnd its relationship to peripheral control, pointing out the importance of the fcrmer. EIBL-EIBESFELDT’S (1970, pp. 41 ff) summary of the evidence, which is persuasive, discusses experiments on quite complex locomotory behavior (some of which experiments were performed prior to 1965). A recent experiment described in FENTRESS (1973) is particularly interesting here. FENTRESS took new-born mice and amputated the forelimbs. The development of grooming behavior (as identified by shoulder muscle activity) was left unaffected, although no grooming could take place. H e concluded that “endogenous control factors must be postulated” (p. 705). In any case, the question of ‘central control’ is to some extent one of depee. VON HOLST has always asserted that some peripheral activity has an influence on even “central nervous automatisms” (a point also made by BULLOCK (1961) in discussing the work of GRAY and LISSMANN). Furthermore, VON HOLST has attempted to eliminate the reflex/automatic dichotomy, claiming that true reflexes are rare, merely the extreme end of a spectrum (e.g., VON HOLST 1939; and cf. LEY- HAUSEN 1954; and SPERRY 1965).

The brain stimulation experiments are rather controversial. In these experiments, electrodes are surgically inserted in places in the brain, and then electrically excited for brief periods, and the animal observed. Generally speaking, the behavior elicited is either a fragment of a FAP or a complete FAP (if any behavior is elicited at all), although some success is reported in

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producing learned behavior (MOLTZ 1965, p. 41). Relevant to the production of a FAP are: the mood of the animal (emphasized by VON HOLST and VON ST. PAUL 1963); the presence of appropriate releasers of the behavior (also emphasized by VON HOLST and VON ST. PAUL); and the position, intensity and duration of the stimulation. VON HOLST and VON ST. PAUL (1963) report the natural performance of almost every FAP domestic fowls possess; they claim widely different behavior depending upon the mood of the animal, and that the same behavior can be elicited from many different points; they hypothesize a complex of centers controlling fixed movements (not necessarily entire FAPs) which interact in various ways depending upon mood and environmental conditions. PHILLIPS and YOUNGREN (1971), in a conscious attempt to dupli- cate the work of VON HOLST and VON ST. PAUL, do not discuss the latter hypothesis; report a lack of natural behavior (but rather the presence of spastic fragments of the FAPs) and claim more success with the spatial localization problem. Finally, they suggest that their inability to obtain ‘natural behavior’ indicates that the FAP is not rigidly programmed in the CNS of chickens. They also claim that their experimental results did not differ from VON HOLST’S and VON ST. PAUL’S since, in their opinion, the behavior which VON HOLST elicited, and which he filmed, was not natural.

That so-called punctate electrical stimulation should produce a FAP, or even a recognizable fragment of a FAP, would be unexpected evidence of central control and “special neural centers”. It would be unexpected for several reasons: first, FAPs are normally elicited by releasers, not purely internal matters; second, hormones and age are crucial factors in the production of some FAPs (LEHRMAN 1962); third, and most importantly, central control does not entail ‘single location’. Indeed, VON HOLST and VON ST. PAUL, as well as PHILLIPS and YOUNGREN, stimulated two points simultane- ously. We have no a priori reason to suppose that each FAP is completely controlled by a single neural center; after all, the same movements may enter into a number of FAPs and, for that matter, reflex and learned behavior. It might well be that these common movements are controlled by separate neural centers which are “made use of” by centers more particularly associated with a single FAP. This, in fact, seems very close to the hypothesis which VON HOLST and VON ST. PAUL suggest to account for their data, and something lather similar is suggested by LEYHAUSEN (1965). It also seems to account for the results of PHILLIPS and YOUNGREN: punctate (i.e. small field) stimulation in such a case would be expected often to produce fragments of FAPs and just plain spastic behavior; the production of a complete FAP would depend upon lucky placing of the electrodes and, more significantly, an antecedent disposition of the bird to perform the FAP together with the appropriate releasers in the environment. If this hypothesis is correct, then we would expect there to be points during some FAPs during which afferent inflow might be important (which could easily lead us to suppose we are actually observing a sequence of FAPs and other sorts of behavior: cf. LEYHAUSEN 1965). A terminological problem also seems to be important here. The ‘Lorenz School’ is quite strict in distinguishing instincts from taxis and learned behavior, even within what is, by other authcrs (e.g., HINDE cited by LEYHAUSEN 1965, p. 223) who are less concerned to make these distinctions anyway, often called a single FAP. Consequently, what is regarded as a refutation of the doctrine of “afferent inflow independence” will naturally vary. Note also that the stereotypy expected by LORENZ is only that of the phase relationships among all the muscles involved, and consequently, rather unnatural-looking

Half a Century on the Concepts of Innateness and Instinct 3 79

activity could still be a FAP (cf. LEYHAUSEN 1954, p. 84). I n any case, PHIL- LIPS’ and YOUNGREN’S conclusion that the FAP is not rigidly programmed in the CNS seems premature - especially in view of CANNON and SALZEN’S (1971) experiments with newly-hatched chicks, which they take to support an innate brain mechanism hypothesis.

The hypothesis of central control was originally made by LORENZ in order to account for the apparent immunity of the FAP to (immediate) afferent inflow (note that MOLTZ 1965, pp. 27, 30, and 40 accepts this as fact) and so to distinguish it from a reflex chain (also agreed to by MOLTZ 1965, p. 30). The hypothesis was suggested (and supported) by some early experiments by VON HOLST (cf. VON HOL~T 1939). The case far central control is quite strong; much of the resistance to the hypothesis has resulted, it seems, from the common coupling of it with the hypothesis of endogenous neural activity, which has excited far more resistance because of some of its implications. And so we turn now to the spontaneity of the FAP.

( 2 ) It appears to be the case that, inexplicably by a purely reflex theory, animals display appetitive behavior, are motivated to seek situations in which they can perform FAPs. Also, there are fluctuations in the threshold of a FAP; as the animal goes the longer without performing a FAP, the likelier it is to perform the FAP intensely in response to inferior releasers. Consequently, FAPs are said to be spontaneous (this dces not entail that any FAP can be set off in the absence of external stimuli), and hypotheses to explain this fact have been debated.

LORENZ’S first supposition involved a reservoir of action specific energy, endogenously produced. As this energy accumulates, the threshold fluctuates and appetitive behavior (directed to the performance of the FAP) begins. This supposition was influenced by VON HOLST’S then recent discovery of the importance of endogenous neural activity. Much work since then has shown the omnipresence of endogenous neural activity and automatic systems in the CNS (cf. BULLOCK 1961; LEYHAUSEN 1954; etc.), and the classical reflex theory has had to be modified accordingly (VON HOLST 1939; SPERRY 1965, p. 163). However, as further experimentation has altered LORENZ’S original analysis of the FAP, modification of this simple reservoir model of motivation has also been necessary. For example, it was discovered that the consummation of a FAP could be conringent on the feedback of the successful effect of the FAP, and not merely on its performance. The influence of hormones has also been accepted. Even more importantly, the influence of physiological feedback on such matters as eating and drinking is now seen to be important. Motivational analysis (even for FAPs) is now a complex matter involving feedback mechanisms and a systems analysis approach (e.g., MCFARLAND 1971, 1974; Mc- FARLAND and SIBLY 1972). However, despite growing evidence for the continued importance of endogenous neural activity (cf. EIBL-EIBESFELDT 1970, for a summary; and FENTRLSS 1973), and for catecholamine reservoirs, which may play a necessary role (EIBL-EIBESFELDT 1970, pp. 59 f ; and cf. SCHILD- KRAUT and KETY 1967; catecholamines appear to be synaptic facilitators which endogenously build up, perhaps in a number of reservoirs, and influence mood and reaction to external stimuli), resistance to endogenous motivational factors (except for circadian rhythms, e.g., J. BROWN pers. comm.) has remained. The reasons for this appear to hinge on certain implications of any motivational analysis which mostly involves endogenous factors.

Suppose there are only feedback mechanisms involving physiological needs, and, say, copulation (here we need to add hormones as an internal

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motivational factor in the biofeedback mechanism). Such feedback mechanisms have two virtues: first, they are essentially ‘rational’ in the sense that they involve reactions to the environment and activity strictly necessary to the survival of the individual (sex is not, perhaps, quite so “rational”, but its necessity is obvious). FAPs involving results not immediately serving such needs would only be elicited by special external circumstances, or when the animal ‘sees’ the need for them in order to serve such needs. For example, aggression would only occur when required (e.g., under attack, when hungry, etc.).

But suppose we now add behavior largely motivated by endogenous neural activity (with the addition of a catecholamine hypothesis). This behavior will, of course, be adaptive in the normal environment; i t will indeed be behavior evolutionarily designed in the furtherance of an individual’s and its offspring’s survival. But it is not behavior which is a simple tool: i t has an independent motivation. Such a behavior (or its immediate effects) is a goal in itself for the individual. From one point of view, then, it can well be irrational behavior. For example, a well-fed cat could, nonetheless, be motivated to hunt and kill (as indeed it apparently is); an individual may be socially aggressive despite adequate supplies of whatever goods such aggression usually secures. There is a strong disinclination on the part of many (e.g., SCHNEIRLA 1966; LEWONTIN 1976; SCOTT 1962) to accept this sort of implication. And if extended to man, the implication can be even more obnoxious. O r so i t may seem: it is only fair to point out that the opposing view - that essentially only ‘physiological needs’ have independent motivational systems - can be equally horrifying. Such a creature is unscrupulous. In order to satisfy hunger, thirst, and the desire to copulate (the position of child-rearing behavior is anomalous here) such a creature will do anything. By the use of rewards, it could be conditioned to perform any action whatsoever.

The evidence for the spontaneity of even such FAPs as aggression, and not merely of those satisfying purely physiolcgical needs, is nonetheless quite strong, whatever one’s attitude towards “action specific energy”, “unitary drives”, reservoirs of this and that, and endogenous neural activity. That is to say that some sort of internal motivating factors able to explain the rise and fall of threshold levels (as a consequence of a variety of factors: e.g., the performance of the FAP; the perception of the results of that performance) and appetitive behavior must be postulated. If aggression is a true FAP, then i t must be spontaneous (in our sense). Aggression and/or its immediate results must be a goal-in-itself, for individuals with such aggressive FAPs. Evidence that hormones are an internal motivating factor in aggressive behavior (e.g., SCOTT 1962), that aggressive behavior can be directed away from its typical targets (EIBL-EIBESFELDT 1970, pp. 214 f ; Kuo 1930, 1933), that there are numerous inhibitory mechanisms (EIBL-EIBESFELDT 1970, pp. 330 ff), that it occurs primarily in reaction to external circumstances (the releasers), or that aggressive behavior can be discouraged by lack of success (CLARK 1962; SCOTT 1962; EIBL-EIBESFELDT 1970) is what one would expect even if aggression is a true FAP. The most striking piece of evidence which I know concerning the question of spontaneity is the fact that cocks and fighting fish can be trained to perform tasks when their sole reward is an opportunity for fighting and threat behavior (EIBL-EIBESFELDT 1970, p. 329). Resistance to the hypothesis that aggression can be spontaneous (in this sense) is nonetheless widespread (CLARK 1962; SCOTT 1962; BERKOWITZ 1962; SCHNEIRLA 1966), perhaps because spontaneity is often equated with ‘‘uncontrollable’’. Yet a reflex,


though not spontaneous, is “uncontrollable”. If aggression is an innate response to certain naturally and frequently occurring situations, we have a grave problem whether or not it is spontaneous; spontaneity is only the bow on Pandora’s box.

Much of the heat behind the resistance to these two Lorenzian facets of the FAP - central control and spontaneity - is due to the attempts by LOKENZ and others to extend the work on the ‘lower’ animals to man. If a number of fundamental human traits, such as aggression or territoriality, are Lorenzian FAPs (or based on such FAPs), then it may be impossible simply to ‘remove’ them; they can, perhaps, only be repressed to some extent and chan- nelled. The actual attempts to attribute FAPs to man have not in fact been very successful. While i t is true that, beginning with DARWIN’S “The Expres- sion of Emotions in Man and Animals” and most recently with the work of HASS and EIBL-EIBESEELDT (cf. EIBL-EIBESFELDT 1970) and LEYHAUSEN (1967), evidence has accumulated that the expression of emotions is often a FAP, and while there is other evidence for FAPs in man (e.g., EIBL-EIBESFELDT 1978), it is also true that FAPish accounts of human behavior in general have been riotably lacking in rigor.

For example, there is a considerable amount of loose talk about such and such a characteristic releasing a feeling, an cmotion, an aesthetic thrill: i.e., mental events, not behavior patterns [a point made against LOKENZ by, e.g., KALIKOW (1976)l. They say aggression is innate, but they do not distinguish kinds of aggression (SCHNEIKLA 1966), and where is the FAP that men use to kill? Where is the species-typical, innate, releaser? Again, how can such an analysis account for the pervasive influence of learning and culture upon human behavior?

It seems to be the case, however, that one can construct an evolutionary theoretical framework which can account for these anomalies, and which is nonetheless a FAPish framework. This is, hcwever, largely speculative insofar as it can be said to be true of man.

We have two sets of facts a t our disposal in an attempt to reconstruct the evolution of human behavior from a FAP-ridden predecessor. First, man is a tool-using animal, and is capable of a high degree of abstraction. Second, we have already modified our account of the FAP in order to permit these three crucial changes: we now permit learning to enter into the development of a releaser [in imprinting, in the ‘learning’ that this plot of land is one’s territory, that this is one’s mate (a necessity in herring gulls, for example), etc.] ; we now recognize the possibility that the perception of the result of a FAP can be a t least part of the consummation of a FAP, rather than its mere performance; even more than a t first, we recognize that FAP’s can be intercalated with reflex and learned behavior and other FAPs. In addition, we must recall that FAPs have been the center of motivational studies in animals, and that the consummations of FAPs have been the appropriate goals of animals.

As ‘man’ became a tool user, the extended motor behavior involved in a FAP would become a hindrance in many situations, rather than an aid. There is no point in using the tried and true motor behavior of sinking one’s teeth into one’s adversary, if clubs and bows and arrows have been invented. Con- sequently, one would expect those FAPs replaceable by learned behavior involving (new) tools to diminish in importance. [This evolutionary trend is not, of course, limited to man; LEYHAUSEN (1965) points out that learned aggressive behavior patterns sometimes supplant innate ones in cats]. On the other hand, since man is a social animal, FAPs serving the ends of communica-

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tion (or those for which tools are valueless, e.g., copulation) would retain their importance. In cases where a FAP served both for social communication and a tool-replaceable motor pattern, we would expect the evolution of FAPs serving the first function, and yet permitting tool using. For example, one would expect aggressive FAPs to be replaced by FAPs involving the expression of emotions (i.e., to some extent, intentions of sorts of behavior) while permitting some latitude in the extended motor behavior leading to their performance. The role of appetitive behavior would grow in importance. An ‘aggressive’ FAP in itself might not involve any aggression! but only a grimace of malice and a sneer of vindictive triumph. Concomitantly, both the releasers of aggression and what constituted consummation of the (now purely expres- sive) FAPs would have to be subject to learning processes. For an animal capable of great abstraction, only the concept of suffering might be needed as a consummation. Due to the often purely cultural differences separating g~-oups and the numerous ways of inflicting suffering, the releasers of aggression would need to become subject to learning. We have already seen this last sort of learning in territcrial-based aggression in other animals. The same sort of learning must also be involved in group agpression in animals (for example, in some rats, where the scent of the group is the releaser; or in social primates where individual recognition is important). In such a case it is easy to see how the subjective emotional aspect of a FAP, and the learning involved (in appetitive behavior, in the releasers, and in the consummation) would attract most attention, although, for example, DAVIS (1962) suggests, in his study of the phylogeny of human gangs, that “probably only the means of fighting and the object of attack are learned” (p. 319).

Probably the evolution surgested in the preceding paragraph is not complete in man. Nonetheless, the line of thought there expressed seems to account for observed human behavior within a FAPish framework. The evolutionary aspect is not dissimilar to that suggested by ERNST MAYR in his “Behavior Programs and Evolutionary Strategies” (1974), i n which he takes the separa- tion of behavior into communicative and non-comniunicative to be a major clue (for selection reasons) as to whether the behavior is a result of an open or a closed genetic program (also, cf. LEYHAUSEN 1967).

The preceding account of human behavior, i t must be admitted, may suggest pessimistic conclusions concerning, if not the extent to which humans are improvable, at least the difficulty of doing so. Historically, observably, of course, they have not much improved. Nonetheless, resistance, as we noticed carlier, to these sorts of conclusions remains strong.

Sum rn a r y

An Unacknowledged Revolution?

In conclusion, I would like to summarize the important changes that have occurred in our ‘paradigms’ of animal behavior and the reasons why some of these changes have gone virtually unremarked, and even been denied when they have been extended to analyses of human nature.

The chief changes in our paradigm that we have analyzed are: (1 ) There is a perfectly plausible and generally accepted notion of the (behaviorally) innate, which is at once developmental and genetic (as it always has been in colloquial discourse), and indeed, evolutionary; (2) There are behavior patterns which can plausibly be called “instincts”, which include behavior not

Half a C e n t u r y on the Concepts of Innateness and Inst inct 383

directly concerned with nourishment and reproduction (e.g., territorial and hierarchy behavior), and arcund which an animal’s life revolves; and (3) The instincts mentioned in (2) are spontaneous (have internal motivational factors) and have many innate characteristics. The genetical influence, then, is important for an animal’s behavior; an animal is active, not merely re-active, a tool of its environment; and, further, the plethora of ‘desires’ which make an animal active are largely just these strongly genetically influenced instincts.

That these are indeed changes in our paradigm we have seen by looking at those who have argued against LORENZ and is most evident when looking at the work of Kuo (1924, 1930, 1933, 1967, 1970), or the recent papers of R. B. LOCKARD (1971) and J. M. JOFFE (1973).

That these changes are, in a sense, unacknowledged can be seen by several facts. H. ADLER and TOBACH’S “comment” (1971) on LOCKARD (1971) simply more or less denies that comparative psychology has fallen, and, in justification of their position, cites LEHRMAN (1970) - even though LEHRMAN claims (1970, pp. 18-19) that there is really n o substantive factual question at issue between himself and LORENZ. And this claim by LEHRMAN is questioned by BEER (1975). MAYR (1974) and KLOPFER (1974) write about the gradual synthesis between the opposing camps which has taken place - which, while perfectly true, does tend to minimize the extent of the concessions which the ‘empiricists’ have had to make. The evidence that the changes are unacknowledged is most striking in the resistance to the sort of extension of the new views to human behavior given above. Yet if we are to include humanity among the animals some such extension must be made.

We can also follow the failure to acknowledge these changes in some of the controversies involving the “p ie t i c determination” of human behavior. For example, WILSON’S “Sociobiology” has met criticism on purely general grounds - and not only on particular errors - in that it commits “the fallacy of biological determinism” (LEWONTIN 1976; Sociobiology Study Group of Science for the People 1976) - which seems to be the ‘fallacy’ that anything is innate. It is obvious enough that much of the resistance to “biological determinism” (even in the form of our weakest definition of the innate) derives from the apparently unacceptable political, social and ethical implications that it appears to have. Why these implications are now thought to be unacceptable (and why they have actually seemed generally to be commonplaces from the ancient Greek period until fairly recently), and whether or not the most un- p la tab le of these implications really follow [e.g., malgrk LEWONTIN (1976), 110 automatic justification of the status quo is generable from sociobiology] are questions which lie outside the scope of this article.

But a point in the history and philosophy of science does remain to be observed. If I am correct a revolution as momentous as that of Copernicus has occurred (or, at least, is occurring: it has not, especially in its application to human behavior, by any means finished, even if the fundamental changes have been accomplished). This revolution has been accompanied by as many “irrational” (i.e. non-scientific) trappings as any other: disturbance of world views (moral and political as well as scientific); the re-definition of old terms; mutual misunderstandings among researchers; the use of moral arguments against a purely - or largely - scientific position; attempts to re-write history in order to minimize the extent of the revolution; and so forth. Because of these one might be tempted to suppose that this “revolution” fits very well the Kuhnian paradigm of a scientific revolution. Further reflection, however, shows that this revolution is not Kuhnian, but rather provides a counter-

3 84 JOHN CASSIDY

example to KUHN'S thesis (and a crucial counter-example at that, because of our revolution's implications about human nature, morals, politics and so forth). The crux of KUHN'S position is that the root causes of paradigm shift are non-rational; but the causes in this case are, at bottom, patently rational scientific experiments and theorizing. This, I hope, is obvious from the whole of this article, and the point is only emphasized by the introduction of means - such as videotape, and statistical and computer analyses - to render the judgments of researchers yet more rational (in that they provide objective criteria for agreement and information for inter-subjective agreement - or disagreement). I therefore claim that an account of this revolution provides a decisive counter-example to the basic Kuhnian claim that scientific revolutions are intrinsically, and inevitably, irrational, even while it illustrates and con- firms his claims about the many irrational trappings which accompany revolutions.

Zusarnmenfassung

Die Arbeit gibt einen Oberblick und eine Kritik der verschiedenen Ver- suche von Verhaltensforschern, ,,angeboren" zu definieren. Eine neue, vor allem auf LORENZ griindende Definition wird vorgeschlagen; sie ist in die heute gebrauchliche Ausdrucksweise von Genetik und Evolutionstheorie iiberfuhrbar. Ein Merkmal ist angeboren, wenn und nur wenn es kanalisiert ist (im Sinne WADDINGTON'S: seine Auspragung ist weitgehend unempfindlich gegen Ver- anderungen der genetischen oder der aufleren Umwelt), wenn jeder Phanotyp innerhalb der Reaktionsnorm, der das Merkmal nicht aufweist, unadaptiv ist und wenn alle Modifikationen das Merkmal zeigen. Eine darauf aufbauende engere Definition trfaf3t das LoRENZ'sche Konzept des Angeborenen und eignet sich fur eine Erorterung der Erbkoordinationen (die - wie aus jiingerer Lite- ratur ersichtlich - auch beim Menschen eine Rolle spielen).

Schliefllich wird aufgezeigt, daf3 in der Verhaltensbeschreibung ein Para- digma-Wechsel stattgefunden hat, und zwar aus vollig rationalen Griinden. Vielerlei Irrationales (auf das die KuHN'sche Philosophie abhebt) wurde nur beilaufig auf den Plan gerufen, kann aber gerade auf diesem Feld die These der Irrationalisten in der Wissenschaftsphilosophie nicht stiitzen.

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Author’s address: John CASSIDY, Department of Philosophy, 455 W. Lindsey, Rm 605, University of Oklahoma, Norman, Oklahoma 73019, U.S.A.

half a century on the concepts of innateness and instinct: survey, synthesis and philosophical...

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