“Spontaneous generation” will not exist, but isolated ponds continue to fill with fish: the mechanism that solves a mystery of hundreds of years
“If we put sweat-filled underwear in a container of wheat, after twenty-one days the smell changes and the ferment, emerging from the underwear and penetrating through the wheat husks, turns the wheat into mice.” In 1667, the famous Belgian naturalist Jan Baptiste van Helmont described like this what for centuries popular lore (and a good part of academia) had called “spontaneous generation.” That is certain life forms arose spontaneously from organic or inorganic matter or a mixture of both.
Today we know that, as is often attributed to Parmenides, “out of nothing nothing is made for“; or what is the same, that out of nowhere, nothing knows. But it must be recognized that many times it is very difficult to explain according to what things. For example, the matter of fish. Because How is it possible that tanks or lakes of pristine water (physically isolated from other water pockets) fill with fish in a short time? Where were those minnows hiding and how was it even possible?
The stork does not bring the fish, but …
Do not think that this is a rhetorical question. On the contrary, the enigma of the empty ponds that were no longer empty was a theme that had very intrigued to 19th century researchers. However, while the most sagacious realized that perhaps the only meaningful option was birds, no one could find a satisfactory explanation.
In fact, we haven’t found an explanation worthy of the name until the end of last year. It was then that picking up the clues what there were releases for literature, a Spanish-Hungarian team publicó en Proceedings of the National Academy of Sciences an interesting study: they fed eight wild ducks with fertilized eggs from two types of carp famous for having starred in episodes like the ones we are talking about.
In total, it was about 500 eggs per duck. From these, the researchers were able to recover 18 intact eggs, three of which hatched, giving rise to three perfectly functional carp. In other words, it is technically possible. Unlikely, okay; but possible: fish eggs can survive a mind-blowing journey through ducks’ digestive tracts.
Considering that an average tent can put up to one and a half million eggs several times a year and that the ducks took around an hour to expel the eggs, with a probability of 0.02% the mechanism appears as a solution to a riddle what had remained unanswered for much more than a century. It didn’t stop us from sleeping, it’s true; but you sleep much better knowing something new.
Photo | Daniel Grounded