the modest birder (10) a biography of Niko Tinbergen

By chance I came across a reference to Niko's Nature. The Life of Niko Tinbergen and his Science of Animal Behaviour. Oxford, OUP., 2003. The title could be a pun; the writer, Hans Kruuk, one of Tinbergen's students and friend of the family, spends some time throughout the book on aspects, often negative, of Tinbergen's character. The reason why I read the book were the (apparently faulty) memories of my teenage years that included having heard Tinbergen address a gathering of NJNers of which I was one. The NJN (Netherlands Youth Organisation for Nature Study - for young people, aged 12-23) played an important role in his life during its early years. I became a member in my early teens during the German occupation in WW II, when Niko Tinbergen was already an established expert in the new science of ethology, the study of animal behavior in relation to the environment. Actually he was then taken by the German occupiers and interned in a hostage camp with other prominent "unreliable and suspect" academics, artists and politicians. Tinbergen's contribution, in addition to helping create ethology, was to insist on field rather than laboratory (Pavlovian) studies (pp.74ff., 80), because he came to the study of animal behavior from his ecological interest in territoriality. He was most interested in the functional significance of species-characteristic behavior for survival in specific ecological conditions. As I read the book it became clear that the Tinbergen I had listened to was Niko's younger brother Luuk (Luke) by then also an academic who expanded on his brother's earlier work. Luke's interest in ecology led to an early publication called Vogels in hun domein (Birds in their Habitat) the 1946 edition of which I received as a birthday present. Luke's own work groups had increasingly looked into the relationships between habitat and behavior of songbirds. Because most of their members were also NJNers, their work was often discussed at district meetings and on excursions. One of those students, not personally known to me, engaged in a sociological study concentrating on the density of songbird populations in precisely mapped wooded habitats. As he sought the cooperation of other NJNers, I undertook to record the nesting birds in a nearby, neglected and overgrown, city park, the same park where my mother used to push me in a pram when we lived across the park's entrance (when it was still maintained as an - (Enlish)naturalistic - park). It involved my getting up at the crack of dawn, walk 45 minutes to the park, map the different songsters and walk to school which started at 9. The study came to nought, for as I learned after 1945, the student was picked up by the Gestapo and disappeared.

As I read this biography I sometimes wondered whether it was translated from the Dutch, but it's Kruuk's native language that comes through (I should talk!) even after all his years in England. Anxious to show how bright the Tinbergen siblings were he twice remarks that two Noble prizes in one family are unique. It is for two brothers, but there are several father and son as well as mother and daughter recipients, the Curie family collecting 5 prizes (2 for Marie, 1 for Pierre and 1 each for their daughter and her husband). Also imprecise is his emphasis on the limited means of the Tinbergen family, the father being a teacher in the Dutch preparatory system for the university, this in spite of the fact that the children were encouraged to pursue a then still expensive higher education - the eldest son, Jan becoming the eminent international economics expert - and that they had a summer cottage in a still wild region of the country (which later became the center of Luke's ecological work groups). By comparison, my own family could be considered poor, which we were not in fact though my brothers only had a trade school education that helped them become likely successors in my fathers house painting business (only one of them did). As the youngest I was allowed to become a white collar member of the educated middle class. Means may have been limited in the Tinbergen family, but a greater factor was a tradition of thrift that was strengthened by the parental Protestantism in both families (non-church going laborers and Catholics I grew up to believe, went to pubs but when my father drank beer it was on Saturday and brought home in a shopping bag).

It appears to me that this biography could have been shorter. Kruuk recounts the many repetitive experiments NT engaged in, first by himself and later with groups of students and the results could have been lumped together once their purpose and organization, which changed little, was described. Though after a while this repetition reinforces Kruuk's discussion of the fact that NT did easily become bored, switched to other subjects and eventually felt he had run out of ideas for new projects. As Kruuk makes abundantly clear, many conclusions drawn from these studies were later corrected by other ethologists, some during NT's active career, and criticism of ethology was not infrequent. This is not surprising as NT was a true pioneer in this new field where Karl Lorenz, Julian Huxley and others were his colleagues. NT and Karl Lorenz together with Karl von Frisch shared the Nobel Prize for their work. Incidentally, having grown up on the edge of the North Sea myself, it is clear to me that the dedication of his students was remarkable as NT insisted that they live a spartan life while in the field under often trying meteorological conditions; even if in the Post-War years and their probably thrifty families they were not used to luxury, living in tents with sleeping bags in very chilly Aprils and Mays when most of the field studies were done, must have been tough. Later Tinbergen organized a caravan to provide some comfort during the day. In Kruuk's day, when NT only came on visits - as his health and academic demands became problems - the students, then including some from America as well, improved their living conditions.

I must say that I felt a great affinity with Kruuk's Tinbergen, warts and all. One of these warts was what Tinbergen himself later referred to as "youthful arrogance," but, like me, he seems not to have shed what was in fact an intellectual impatience with others. And I too was a truant, preferring the open fields around our home over the classroom and, like NT was inspired by the popular nature books of Jac. P. Thijsse and E. Heimans. For even longer than NT, I could not settle down after high school. Because there was no academic tradition in our family with its possibility to use connections, I became rather a vagrant, occasionally taking jobs as a merchant mariner, as a gardener in the Savoie and even as a semi-professional soccer player (the French there being convinced that all Dutchmen were great players). I resisted formal drawing lessons in school - both my brothers were gifted with the pencil and the oldest, called Jan (like Niko's older brother), became a talented amateur landscape painter, yet my own nature notebooks were full with pretty good drawings of flowers and birds (readily improved by brother Jan) and if I had stuck to it, who knows? Again, like Niko, I wanted to be a nature photographer, but unlike him, once I acquired a camera I abandoned the drawings, though I don't think I would have ever achieved the level evident in NT's lovely figures that illustrate this biography, nor did I persist with nature photography. Like NT, I also felt enclosed by Dutch middle class mores, the lack of space and career opportunities. In the early 20th century the hierarchical class structure was slow to unravel and Dutch society was relatively stagnant. In my case the biblical tale of the twice seven years that Jacob was to work for his uncle Laban was occasionally brought home by the golden watch handed out for one's 25 years of loyal service. My marriage to an American who did not want to start a family anywhere but in the US, also brought academic connections and I began to study seriously. But like Tinbergen, I remained restless and was eager to move, but just like Tinbergen was stopped by his wife, so too was I. All my moves were limited in space to Southeastern Pennsylvania where my late wife believed there were better early childhood educational opportunities for our two children. Also like Tinbergen I became bored with a subject once I felt I had learned enough and further study would be repetitious; from the 19th century Industrial Revolution I descended to the 16th century and settled down in Medieval ecclesiastical and art history. Perhaps it was our Calvinist background (which must have caused tensions with our own life in the NJN, an organisation run by its members and anti-establishmentarian),that Kruuk suggests was what made NT insist that one could not dally around and that work should lead to results (which my father made clear by an occasional interruption of the sequential after dinner readings from the bible to read the last verses of Matthew 25 about the "parable of the talents"). Not the least reason for for my own changes of subject was the fact that they permitted extended (and subsidized) travel, led to rapid promotions and at the end allowed me to teach whatever I felt like, including photography. On its less exalted level, my life parallels that of NT in many ways.

When I was trying to become a bird photographer, I also played around with a variant of Tinbergen's studies on the colonial nesting behavior of gulls without any precise formulation of what I was looking for. In my case it was a small colony of Common Terns in a meadow near our house. I replaced the eggs in a nest (not much more than a hollow in the grass formed by the wiggling of the bird's body) with fake white pigeon eggs and placed its real eggs about two feet away. The tern landed exactly as always, about a foot behind its nest. It stayed there and looked at the white eggs, then at the real eggs. The tern flew away. A few minutes later it came back after circling over head. It landed between its own and the pigeon eggs, looked left and right at both sets, walked over to the pigeon eggs in its nest and sat on them. Another time I left the nest empty and placed the tern's eggs a few feet away. The same thing happened, except that the tern did not sit down on the empty nest but flew away. After I had put the eggs back and the tern returned, it landed behind the nest, walked to it and sat down on the eggs. One could say that in this case the place of the nest was decisive though the bird seemed to recognize that the pigeon - or white - eggs were as different as an empty nest. But did the bird know that the eggs were its own? After it abandoned its empty nest, would it have laid new eggs in a different place? Tinbergen later did experiments in which gulls (and other birds) rolled an egg (even a much larger one) placed outside its own nest into the nest and sat on all the eggs. In my experiment I probably placed the eggs too far away and they were left where they were. I did not carry the experiment very far (mostly because none of my friends who were to get me to and from my blind were willing to play hooky as often as I did, though one year a farmer's son would interrupt his work in a nearby field to help out). In the weeks that I was studying them no tern nest was robbed so I did not find out whether terns would lay again once they had abandoned an apparently empty nest. Moorhens, coots and ducks whose eggs I had taken home for food during the war had laid more eggs or built new nests.

Another year, I replaced the real eggs with fake pigeon ones that my brother Jan had painted to resemble the eggs of terns, the parent tern hesitated also between its own eggs that again I had place about two feet away, but rather than fly away and return, it cocked its head several times, after which it sat down on the fake ones. The importance of "place" or site tenacity, which also causes terns to return each spring to the same area to breed, may also have been why a tern, that I recognized by a missing tail feather, sat down on its own nest without hesitation even though I had switched its eggs with eggs that had larger and darker spots from another nest. Both sets were incubated normally and the chicks fed by the hatching parents on which the chicks had imprinted. But, after reading studies about the mind of birds, I now wonder how many of these tests are needed to move from the anecdotal to establish a theory of a bird making a choice.

Actually I paid more attention to the “getting of the great shot.” Yet, other puzzling aspects of bird behavior are buried in my memory. One of these concerns Lapwings. They were invariably warier of my blind (even if it was not near their own nest but near that of a Godwit about 50ft away across a small ditch) than any other meadow bird. While warier in a meadow without terns than with terns, in each case the Lapwing returned to its nest later than Redshanks, Godwits or Reeves (the female Ruff). It landed at a greater distance from the nest than those I observed when hidden in my kayak behind phragmites, and it took longer to approach its nest and to sit down. It seemed that the blind (made of - double - burlap potato sacks and painted green) made the difference. Nol Binsbergen, a professional photographer, whose heavy equipment I had sometimes been privileged to carry in my early teens, believed that Crows could count for they would not return to their nest unless he was accompanied to his blind by more than one person (who had to climb his tall ladder). This was the case also with the Lapwings outside the tern colony. I do not know whether they could count, perhaps three people were sufficiently confusing so that when two left, the breeding bird landed more quickly, although it still stood some feet behind the nest looking at the blind much longer than the Redshanks or Godwits did. The breeding Lapwing in the tern colony came back even though I had been taken to the blind by only one friend, perhaps because when the friend paddled away, all the other birds returned to their nests, led by the terns (who had loudly and aggressively seen her off). Lapwings may have been slower in returning because they nested in parts of the fields with low grasses and thus could see more of what was out of the ordinary. I would be hard put to decide what came first, nesting in open spaces with a high sense of suspicion or the reverse. I am inclined to the former as their eggs (marketed as "plover eggs") have been prized for centuries and their breeding in low grass helps the hunter in locating the nests. If there was something like what biologists call "evolutionary strategy," would successive generations of Lapwings have started to breed in high grass like the Redshank or the Reeve, whose eggs were much more difficult to find? Tinbergen made a film demonstrating the survival of light colored moths on paper birches and their darker colored relatives on bark that had been darkened by industrial smoke (the problem known as "industrial melanism"). This was a question of relative visibility making it more difficult or easy for a bird to pick them off and in each case the survivors would, if they lived in isolation from each other, breed a next generation of pretty much the same shade of color. In my West. Civ. Survey classes, whenever questions were raised about Darwin's theory of evolution, I argued that natural selection could best be understood not as conscious selection by an individual animal, much less of a species, but by an (accidental) interplay of environmental conditions (at the time DNA had just been discovered and I was blessedly ignorant of helices, genomes and switches). I speculated that Lapwings which might have hatched in the taller grass of unmowed meadows or meadows grazed by cows rather than sheep (that virtually "shave" the grass at the soil), might subsequently nest in tall grass and if all the eggs in short grass were found and taken there would eventually be no more "short grass" Lapwings. But other factors might prevent this evolution, for example Lapwings, like most of their plover relatives have short beaks and short grass makes foraging easier and there's the fact that its relatives tend to breed on such flat open spaces as beaches or golf courses (where I saw my first Killdeer nest). Richard Dawkins, one of NT's students, summarized in the 1970s the evidence that animals behave for the good of themselves and their offspring but never for that of the species or other species in a habitat (p.120). [Addendum: I didn't pursue this, but I wonder whether Dawkins was reacting to the preliminary discussions of Vero C. Wynne-Edwards who in the 60s had developed a contrary conclusion, namely that "the self-interest of individuals must have been subordinated to the long term interest (i.e. survival) of the group and species to which they belong.] One of the merits of Kruuk's biography is that he shows clearly how Tinbergen's theories on animal behavior evolved, partly as a consequence of exchanges with other ethologists (for instance at a 1949 Cambridge symposium, pp. 147ff.), partly as a result of the work of his different groups, which Tinbergen recognized (p.88) and in particular through a process of constant reexamination which led to such major publications as The Study of Instinct ([1947-8]1951) or "Aims and Methods of Ethology" (1963) discussed on pp. 218-222, in which NT once again stressed the need for observation and description of behavior in the field. His attitude is nicely summed up in an autobiographical essay, "Watching and Wondering," contributed to Studying Animal Behavior (ed. D.A. Dewsbury), Chicago, CUP, 1985, 431-463. And it is in fact what I did in the tern colonies; my answers came gradually as a result of reading NT or other scientists. In addition to NT's research and publications his training of students with a "clear questioning and pragmatic approach to science"(p.343) may, as I see it after reading this biography, have been NTs more lasting achievement. In my case, his work as it was discussed among NJNers, stimulated my youthful curiosity.

Incidentally, Dawkins' argument that birds do not behave for the good of other species in a community, made me think about the effect of the terns in one of the colonies (=A) that I observed for a few Springs which appeared to have a larger number of other meadow breeders in its immediate area than the strips of meadow beyond a circle with a radius of about 50 yards from the edge of the colony. These strips were separated from the colony by the normal system of ditches and canals; and all parcels were in fact rectangular islands. The other colony (=B) had one pair of Blackheaded Gulls but no other breeders on the same island and the reason for the difference may have been the fact that in this colony the grass was shorter when nesting began as it had been grazed by cows (which had been moved to another island). But at the time I believed that the presence of Redshank, Reeve, Godwit and other nests in colony A was due to the aggressive behavior of the terns whenever a predator approached and which appeared to be exploited by the other species. But Redshanks, Reeves and Grasspeepers also prefer to nest in tufts of grass and there were enough of those in and around colony A. Colony B was on higher ground and the meadow was dryer (my pants stayed dry even after a morning sitting on the grass in my blind). The only other nest near B was that of an Oystercatcher about 30 yards away across a narrow ditch and they were yet more aggressive and loud than the terns in defense of their territory. On the other hand, colony B had a Mallard and a Shoveler on nests in the rough weeds on the edges of the island as well as a Moorhen in the phragmites across the wide canal behind my blind.

Possibly my conclusions at the time resulted from the cultural paradigms of my education. Traditional interpretations of the biblical story of creation (man created in the image of God) and the ideas of the Enlightenment with, among others, the improvements made by people, reinforced the then common assumption that the difference between human beings and animals is the fact that humans normally develop their capacity of thought; distinguish between "good" and "evil", "safe" and "dangerous;" can sort out complex stimuli and have a memory of choices made and their consequences, or at least of parental commentary on the choices and the "I told you so" reminders. Thus people learn and adapt or, at a minimum, they can be conditioned. My failures in the training of several dogs to distinguish between kerb and side walk have reinforced the stereotypical difference between teaching another and adapting oneself (when at last the dog appeared to have figured it out, I too had changed, a good example of the joke commonly told about Pavlov's dogs). Even the importance of instinct could be understood in terms of God's creation and I once heard a scientist colleague argue in the weekly school Assembly that evolution in the Darwinian sense was made possible because of what was inherent in a species' creation. The ethological studies sought to establish that animals too can learn or be conditioned, though as far as what looks like memory is concerned it still seems to me a matter of an instinct of self preservation and genetic imprinting. But then, I'm not an ornithologist or animal behaviorist.