The only one on Earth. There's a unique plant that explodes, scattering its seeds (video).

It is not often that plants can puzzle scientists, but this is certainly one such case: researchers have finally uncovered the mechanism behind the peculiar seed dispersal of the squirting cucumber (Ecballium elaterium), which has evolved to cope with a lack of wind, reports IFLScience.

In a new study, a team from the University of Manchester and the University of Oxford managed to capture the mechanism by which this plant disperses its seeds over a distance of about 10 meters. Moreover, the scientists believe it is the only plant in the world that ejects seeds in this unique manner, which is not found elsewhere in the plant kingdom.

The authors of the study suggest that the plant has evolved to overcome the need for wind in seed dispersal — a process that is crucial for the distribution of many other plant species.

We now know that when the time for seeds arrives, the parent plant explodes, scattering seeds around it at a distance of about 10 meters. The cucumbers use a high-speed jet of pressure to achieve this; however, scientists caution that the Chinese witch hazel still holds the record for the longest seed dispersal distance.

Researchers believe that the explosive nature of seed dispersal likely offers several advantages. Firstly, such scattering reduces overcrowding; secondly, it diminishes competition among offspring. This impressive adaptation has prompted scientists to ponder how they manage to achieve this.

In the new study, the scientists focused on uncovering this mechanism. They utilized a high-speed camera capable of capturing up to 8,600 frames per second. Additionally, measurements of the dispersing cucumber plants were taken before and after the seed ejection. Furthermore, a time-lapse recording of the plants was created in anticipation of the dispersal day, along with CT scanning.

The results revealed four key stages of the process:

• the fruits swell, filling with a "viscous liquid" several weeks prior to dispersal;
• days before the launch, part of the liquid spreads to the stem, making it longer and thicker;
• the day begins with a rapid rebound of the stem tip from the fruit, causing the fruit to rotate in the opposite direction;
• the seeds are sent flying.

Researchers note that the third stage is likely the most surprising, as the squirting cucumber is considered the only species in the plant kingdom that does this. Once the seeds are launched, they are distributed over a distance of 2 to 10 meters from the parent plant.

Interestingly, this plant attracted the attention of ancient Roman authors, yet we have only just unraveled the mystery of its seed dispersal mechanism today.