Buzz
While some plants rely on simply dropping their seeds and crossing their fingers, many species have evolved clever mechanisms for seed dispersal that help ensure their survival. Some seeds take to the air, like the fluffy pappus of dandelions. Others are consumed by animals, passing through their digestive systems before being... released. Some hitch a ride via Velcro-like burs that irritate hikers.
For plants with a no-nonsense approach, there's a strategy known as “ballistic dispersal”: firing seeds over significant distances. A notable example is the dynamite tree from South America, whose pumpkin-like fruits create a popping sound when they burst, launching seeds up to 100 feet away.
One of the most renowned ballistic dispersers is Ecballium elaterium, or the squirting cucumber. When its fruits ripen, they explode, shooting goo-covered seeds as far as 10 to 20 feet or more. You can watch the spectacular squirting action in slow motion at the 2:09 mark in the video below.
The mechanism behind this seed explosion has long been a mystery. However, a recent study published in the Proceedings of the National Academy of Sciences reveals that a team of British scientists used high-speed cameras, image analysis, and mathematical models to uncover how this tiny gourd is capable of propelling its seeds over such impressive distances.
The researchers discovered that a thick, viscous fluid gradually accumulates in the cucumber’s pods over several weeks, creating a pressurized system that ultimately powers the seed launch.
Through time-lapse photography, it was observed that the cucumber’s stems changed their orientation before the burst. They tilted from an upright position to a 45-degree angle, crucial for the effective distribution of seeds. Without this change, even with immense pressure, the seeds would likely fall close to, or on top of, the parent plant.
The squirting cucumber rarely misses, according to the study. Over many generations, its seeds consistently traveled distances between 13 and 39 feet. This dispersal technique minimizes competition for resources by spreading seeds away from older plants of Ecballium elaterium.
Thanks to this distinctive method of seed dispersal, the squirting cucumber has expanded its range across Europe, into northern Africa, and even into temperate regions of Asia.
