Charles Darwin’s observations of his son’s laughter

Charles Darwin with his eldest son William
Charles Darwin with his eldest son William

Did you know that Charles Darwin was the first scientist to study laughing babies? Darwin is so famous for his theory of natural selection that it overshadows some of his other landmark contributions to science. His observations of nature alone would have have made him famous. His book was so far ahead of its time “The Expression of Emotions in Man and Animals,” that it came 60 years before ethologists started studying the same questions and about a 100 years before the psychological study of emotions was taken seriously.

His observations of his favourite son ‘Doddy’ lead to another overlooked masterpiece “A biographical sketch of an infan”. One of the first observational accounts of infancy. It was published as a short paper in the philosophical journal Mind in 1877, 18 years after ‘On The Origin of Species’ at a time when Darwin was world famous. In one section, he reflects on what makes Doddy laugh:

A biographical sketch of an infant – Charles Darwin

Pleasurable Sensations.
It may be presumed that infants feel pleasure whilst sucking, and the expression of their swimming
eyes seems to show that this is the case. This infant smiled when 45 days, a second infant when 46 days old; and these
were true smiles, indicative of pleasure, for their eyes brightened and eyelids slightly closed. The smiles arose chiefly when looking at their mother, and were therefore probably of mental origin; but this infant often smiled then, and for some time afterwards, from some inward pleasurable feeling, for nothing was happening which could have in any way excited or amused him. When 110 days old he was exceedingly amused by a pinafore being thrown over his face and then suddenly withdrawn; and so he was when I suddenly uncovered my own face and approached his. He then uttered a little noise which was an incipient laugh. Here surprise was the chief cause of the amusement, as is the case to a large extent with the wit of grown-up persons. I believe that for three or four weeks before the time when he was amused by a face being suddenly uncovered, he received a little pinch on his nose and cheeks as a good joke. I was at first surprised at humour being appreciated by an infant only a little above three months old, but we should remember how very early puppies and kittens begin to play. When four months old, he showed in an unmistakable manner that he liked to hear the pianoforte played ; so that here apparently was the earliest sign of an {esthetic feeling, unless the attraction of bright colours, which was exhibited much earlier, may be so- considered.

Charles Darwin (1877) A biographical sketch of an infant Mind, 7, 285-294

Good to see that old reliable peek-a-boo raising a laugh. But isn’t somewhat surprising, given the stature of the author, that other scientists have largely ignored the laughter of infants in the following 135 years?




Baby Laughter project scientific statement.

The Baby Laughter project is run by scientists at the Babylab at Birkbeck College, University of London. We use a range of methods to study how babies learn about the world. This survey is our latest attempt to understand about the remarkable and all important changes that happen in the first few years of life.

The Baby Laughter project is a set of online survey for parents of babies and toddlers to see if there are developmental changes in what makes babies laugh at different ages. The aims are two-fold. Firstly to see how laughter changes in the first two years of life and secondly to see if those changes track other milestones in cognitive development.

My hope is that we will find some evidence that babies’ laughter is a good index of what they understand about the world at different ages. Laughter is a strangely neglected topic in developmental psychology (Rothbart, 1973; Nwokah et al 1994; Reddy, 2001; Kawakami et al, 2006). But it is one which could provide interesting new insights into infant cognitive development. We also expect to confirm the findings in the adult literature (Provine, 2000) that most laughter is primarily social in nature, By finding out what situations, people and events babies find most amusing and entertaining at different ages, we hope to provide a new perspective on infants’ social and emotional development.

The participants will be parents of babies (two years old and under). They will be recruited online via the project website itself (, from the CBCD participant database and via parenting websites and by individual recommendations and social media. We aim to recruit at least 200 participants for each of the two surveys, but ideally many more.

A set of two online questions for parents asking them about things which make their babies laugh.
Full survey – The causes of infant laughter
9 sections, ~60 questions, 15-30 minutes to complete
Questions about baby and family background, causes of laughter, funny situations, places, times of day, interactions with people. In addition to the questions prepared specifically for this survey, participants can optionally answer a set of standard questions about infant temperament (Very Short Infant Behaviour Questionnaire, Gartstein and Rothbart, 2003)
Very short ‘field report
6 questions, 2-5 minutes to complete
A very short survey asking the parent to describe a single incident of infant laughter.Questions ask for infant age, details of who was present, where and when the event took place and what happened.

From the long survey, we hope to discover what toys, games, sensations and interactions cause babies to laugh the most. How early does social laughter start? What are the primary causes of laughter in infancy? Do these change with cognitive development? Is laughter influenced by, family size, socio-economic status, temperament, etc
From the shorter survey, We hope to accumulate evidence in support of the hypothesis that babies laugh most at events and activities for which they are just starting to understand the relevant features of the world. Laughing at falling objects as physical intuition develops, etc.