Floyer and the man-faced pig

This is from my forthcoming book with Malte Ebach.


Floyer’s monster pigs and his use of homologies to eliminate the interspecies breeding claim

In 1699, John Floyer reported upon a claim of interspecies breeding: human–pig. He had shown to him by a breeder in Staffordshire a new-born pig with what appeared to be a human face:

Contrary to the claim made by some that this was due to interbreeding between humans and pigs, a view quite common in the literature on natural history from the Greeks through to the modern era, Floyer observes that the teeth, pelt, nose, and bones are generally those of a pig, and that the similarity to human faces is due to distortion “whilst the Bones were Cartilaginous” in utero. He thinks it is due to mechanical distortion, but whatever we might now think of fetal deviation in development after such things as the thalidomide scandal, Floyer is using homology to overcome a mistake in classification made on the basis of analogy. He wrote:

I was further convinced in Opinion that there was really no mixture of the two Species in this Monster, by the Woman’s account who saw the Sow take the Bore[sic], and after the sixteen Weeks, on the beginning of the seventeenth, which is the usual time, the Sow pigged [bore] eight Pigs, the first five were perfect Pigs, the sixth was the Monster, and after that two more perfect Pigs, all which I saw sucking the Sow, and as well shaped, and as large as possible…

Floyer is appealing not only to the species homologies of anatomy, but also to the species homology of development. He makes this explicit, when thinking of the Mule:

… the Female contains in her Eggs the first Rudiments of the Animal of her Species, and … the impregnation only changes some of the extremities into resemblance of the Male.

This is a view widely held at the time: the male changes but does not cause the inheritance of the species-typical traits. He goes on to argue that this is a general law of biological inheritance. Assigning a monster to a single species is a remarkably modern thing to do for the late 17th century. Most monsters were thought to be hybrids from Aristotle’s writing onwards. That he uses observation rather than theoretical presumptions is telling also, but clearly what is observed are traits that are held to be somehow informative as to the taxonomic relations between pigs and humans.

Floyer, John, and Edward Tyson. 1699. A Relation of Two Monstrous Pigs, with the Resemblance of Humane Faces, and Two Young Turkeys Joined by the Breast. Philosophical Transactions of the Royal Society of London 21:431-435.

3 thoughts on “Floyer and the man-faced pig

  1. I had to read it to see if he had also rebutted female imagination as a possible cause. I note he did. It would have been an obvious secondary line of attack on his argument.

    He also rebutted the notion that the monster had a distinctive cry (in this example like a human baby) and appears to relate that directly to fiction and want of proper observation.

    That is impressive, its a highly emotive motif associated with such creatures that appeared to cause particular anxiety (although it may also have entertained in the way such horror does).

    He has carefully thought through his argument not just rejecting theoretical assumptions but would appear to have taken considerable care, ensuring that he is challenging commonly held cultural assumptions and directly rejecting key elements of narratives that are live at the time (still are) in popular culture that support a wide web of related beliefs.

    Science may not be modern but the way he has constructed his argument to deal with key theory and key elements of popular culture; it stands up rather well in relation to a lot of later work I have seen, in this regard.


  2. From Aristotle, On the Generation of Animals IV.3 (Translated by Arthur Platt, eBooks@Adelaide, 2004)

    Also, if we assign only one sort of cause, it is not easy to explain all the phenomena, (1) the distinction of sex, (2) why the female is often like the father and the male like the mother, and again (3) the resemblance to remoter ancestors, and further (4) the reason why the offspring is sometimes unlike any of these but still a human being, but sometimes, (5) proceeding further on these lines, appears finally to be not even a human being but only some kind of animal, what is called a monstrosity.

    For, following what has been said, it remains to give the reason for such monsters. If the movements imparted by the semen are resolved and the material contributed by the mother is not controlled by them, at last there remains the most general substratum, that is to say the animal. Then people say that the child has the head of a ram or a bull, and so on with other animals, as that a calf has the head of a child or a sheep that of an ox. All these monsters result from the causes stated above, but they are none of the things they are said to be; there is only some similarity, such as may arise even where there is no defect of growth. Hence often jesters compare someone who is not beautiful to a ‘goat breathing fire’, or again to a ‘ram butting’, and a certain physiognomist reduced all faces to those of two or three animals, and his arguments often prevailed on people.

    That, however, it is impossible for such a monstrosity to come into existence—I mean one animal in another—is shown by the great difference in the period of gestation between man, sheep, dog, and ox, it being impossible for each to be developed except in its proper time.

    This is the description of some of the monsters talked about; others are such because certain parts of their form are multiplied so that they are born with many feet or many heads.

    The account of the cause of monstrosities is very close and similar in a way to that of the cause of animals being born defective in any part, for monstrosity is also a kind of deficiency.

    On another place, Aristotle suggests that not only differences in gestation period will prevent hybridization, but “physical incompatibility” between parents will be a problem, to begin with.


  3. “……..it being impossible for each to be developed except in its proper time………others are such because certain parts of their form are multiplied so that they are born with many feet or many heads.”

    How many thousand years would pass between this wondrous piece of insight and our learning that genes switch on and off in foetal development?


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