In the dark waters of swamps, the alligators hide a millennial secret which makes them even more formidable predators than we imagined. These prehistoric reptiles deliberately swallow stones to transform their bodies into a perfected hunting weapon. A recent scientific discovery has just proved what indigenous peoples had known for centuries: this strategy spectacularly increases their underwater predation capacities.
An ancestral wisdom confirmed by science
For generations, the Amerindians have observed an intriguing behavior among the Crocodilians: these formidable predators voluntarily ingested pebbles. Far from being accidental, this practice seemed to serve a specific objective that modern science has finally elucidated.
In 2019, a team of researchers from the University of Utah decided to put this ancestral hypothesis to the test. Their experimental protocol was as rigorous as it is bold: to compare the diving performances of seven young American alligators with and without these mysterious stomach stomachs.
Results that challenge the imagination
The conclusions of this study exceeded all scientific forecasts. Without their mineral ballast, the alligators managed to stay immersed for about six minutes on average. But once equipped with their gastrolehes-scientific term designating these swallowed stones-their underwater endurance literally exploded.
The average diving duration climbed eleven minutes, a phenomenal improvement of 88%. Even more impressive, the maximum dives recorded an increase of 117%. The absolute record spoke of itself: a basic performance of 14.7 minutes, some specimens reached the amazing bar of 35.4 minutes of continuous immersion.
Each alligator tested has seen its abilities improve at least five additional minutes, testifying to the universal efficiency of this technique in the species.
Credit: ISTOCK
Credits: Sofia Pagan/Istock
A hunting weapon perfected by evolution
This remarkable transformation is explained by a physical mechanism of an elegant simplicity. The ingested stones act as a natural ballast, allowing reptiles to maintain optimal hydrostatic balance under water. Thanks to this additional weight, they can completely inflate their lungs without risking involuntarily going up to the surface.
This technical feat gives them a decisive double tactical advantage. On the one hand, they can remain motionless at the bottom of the rivers during extraordinary periods, transforming each look into a deadly trap for their prey which approaches without distrust. On the other hand, this respiratory endurance allows them to execute their signature hunting technique: the controlled drowning of their victims by underwater rotation, a formidable maneuver called “Death Roll”.
A prehistoric heritage of millions of years
This behavioral strategy does not constitute a recent innovation of evolution. Paleontologists have uncovered numerous plesiosaur fossils – these mesozoic marine giants – containing stones accumulations in their abdominal cavities. The frequency of these discoveries excludes any coincidence and reveals a fascinating evolutionary continuity.
These Jurassic and Upper Cretaceous marine reptiles, who disappeared over 65 million years ago, already used this bury control technique. This persistence through the geological ages testifies to the remarkable efficiency of this adaptation.
The ingenuity of nature in the pure state
Beyond its spectacular aspect, this discovery illustrates the sophistication of adaptive strategies developed by the living. The alligators are not content to be formidable predators by their jaws and their brute force: they have also developed a biological technology allowing them to optimize their hunting environment.
This scientific revelation reminds us that even the strangest animal behavior can hide evolutionary logics of surgical precision, shaped by millions of years of natural selection.
