Ancient History & Civilisation

Spontaneous Generation:
Birds, bees, wind in the trees

When it came to reproductive matters in the natural world, most Greeks had myopia. Granted, it’s easy to miss the mating antics of insects and worms, and watery species from eels to shellfish. Instead of supposing that their methods of reproduction took place far from prying human eyes, natural scientists of that time preferred to believe that certain species had the knack for spontaneous generation. No parents needed.

Aristotle, for instance, announced that caterpillars reproduced from dew, grubs came from dung or fig trees, gnats from timber, and worms from snow or putrefying sap. Furthermore, he taught that bugs emerged from dried sweat, flies from vinegar slime, and certain winged insects from fire. He wasn’t alone, either.

It was widely believed that the common cicada sprang from the spittle of cuckoo birds—and that bees never mated, instead buzzing to life from putrefying matter. While the wild bee population quietly went about reproducing itself, honey-gatherers and beekeepers in every corner of the Greek world wasted a lot of time slaughtering oxen, leaving them to rot, and anxiously awaiting a new batch of bees to form in the stinking carcasses.

Aristotle was far from being a theoretical intellectual. Unlike Plato, he enjoyed empirical field research; he even spent his honeymoon grubbing around the tidepools on the island of Lesbos. (This may say more about his marriage than his vocation.) He took copious notes on his work, insisting later that eels grew spontaneously from mud. He also claimed that mussels, oysters, hermit crabs, and the murex (a nearshore mollusk valued for its purple dye) grew out of the slimy gunk that formed on the bottoms of ships.

Even when observing mammals and larger creatures, the Greeks utterly failed to spot any X-rated action, giving rise to widespread beliefs that mice reproduced by licking salt—or, in a pinch, by licking themselves. Fantastical theories abounded. As Pliny the encyclopedist confidently wrote, “We have it from many authorities that a snake may be born from the spinal marrow of a human being.”

The generative powers of the wind were blamed for the conception of some animals. Breezes, especially the wayward one called “the fecundating spirit of the world,” could impregnate mares, sheep, and tigers. Fowl too could produce what were called “wind eggs.”

When Christianity really got rolling in the second and third centuries A.D., church leaders often used the widespread belief in spontaneous generation and wind impregnation to defend the virgin birth of Christ. Church father Augustine helpfully pointed out that Noah didn’t have to stock the ark with two of every species, since insects and other creatures could do their own generating.


Although Greeks and Romans adored honey and kept bees, they also subscribed to the mad belief that new bees sprang from the rotting corpses of livestock.

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