Social Behaviour in Animals: With Special Reference to Vertebrates

Tinbergen argues that social behaviour—the cooperation between individuals of the same species—is a biological phenomenon that can be studied through the same comparative method applied to anatomy. He identifies three linked problems: function, causation, and evolution. Crucially, he reframes intraspecific fighting not as the opposite of cooperation but as a regulated component within it. In herring gulls, fighting between males occurs simultaneously with the cooperative behaviours of pair formation, nest building, and courtship feeding. Fighting serves to space territories, select mates, and establish peck orders—all of which enable cooperative social organization rather than undermine it. This integrated view distinguishes his approach from treatments that isolate aggression as a separate topic.

The book was first published in Dutch in 1946 as Inleiding tot de diersociologie (Introduction to Animal Sociology). The English edition, published by Methuen in 1953, is described by Tinbergen as a revised translation rather than a literal one. It went through several reprints, with a notable 1990 facsimile reprint featuring a new foreword by G. P. Baerends that details Tinbergen's views on the reissue before his death in 1988. A Chinese translation by Liu Xiaotao, based on the English 1964 edition, was published in 2021. The English edition includes 69 line illustrations and 8 plates, many of which overlap with those in Tinbergen's earlier The Study of Instinct.

The Study of Instinct (1951) covers the entire field of animal behaviour, including methodology, motivation, and development. Social Behaviour in Animals is narrower in scope but deeper in detail on one specific domain: relations between two or more individual creatures. British Birds noted that while there is considerable overlap in examples and illustrations, the later book is "for the field ornithologist the more interesting of the two" because it reviews more facts and less background technique. The book is also more focused on the three biological problems—function, causation, and evolution—applied specifically to social phenomena, and it concludes with practical advice urging amateur naturalists to continue contributing to animal sociology.

Releasers are specific sensory stimuli—colours, movements, shapes, sounds—that innately trigger social responses in conspecifics. Tinbergen argues that social coordination depends on these signal-response mechanisms: the red throat of a male stickleback releases aggression in rival males but courtship in females; the red patch on a herring gull's bill releases pecking in chicks. The book's chapter on the analysis of social co-operation systematically reviews releasers across species, distinguishing the actor's behaviour (the signal) from the reactor's behaviour (the response). This framework explains how animals coordinate mating, parental care, and group cohesion without individual recognition or learning, though Tinbergen acknowledges that experience refines these innate mechanisms.

Tinbergen argues that the contribution of amateurs to animal sociology is not only possible but "very desirable," because lack of specialised training has advantages as well as disadvantages. He deprecates the situation in which research becomes the monopoly of professional specialists, leaving amateurs feeling they cannot keep pace. He contends that training gives knowledge and discipline of thought but often tends to smother originality of outlook. The concluding chapter, "Some Hints for Research in Animal Sociology," stresses that careful observation and simple experiments are within the reach of non-professionals. The British Birds reviewer praised this stance, noting that Tinbergen's own book was an authoritative survey that could help amateurs keep abreast of a literature much of which is accessible only to German readers.

The book's core framework—analysing social behaviour through function, causation, and evolution—became foundational for ethology and anticipated Tinbergen's later formalisation of the four questions in his 1963 paper. The concept of releasers and sign stimuli remains central to behavioural biology, though later research has shown greater plasticity and learning in many systems than Tinbergen's early emphasis on innate mechanisms suggested. The 1990 reprint's reviews in Nature and BES Bulletin called it a classic that "remains as valid today as in 1946" and noted its influence in establishing many vocations. It is now read as a historical milestone in the biological study of social behaviour and as a model of accessible scientific writing.