Mini ‘Hand Grenades’ Explode Evolutionary Ideas

Even a glance at the cucumber-like fruits Ecballium elaterium would reveal nothing remarkable, and certainly would not make anyone think of hand-grenades.

Not, that is, unless someone were to try to pick one of these lettuce-green, rough-coated ‘cucumbers’, in which case he would find to his astonishment that it would seem to literally ‘explode’ in his hand, spraying its fluid contents all over him.

Gooey grenades

Unfortunately, he will not just have been sprayed with quick-drying, harmless water; he will soon discover that the small, oval, brown seeds of this plant have been scattered over his clothes, clinging by means of a bittertasting, slimy, sticky fluid.

Of course that is the purpose of the exercise from the plant’s point of view. With no-one in the way, the seeds, which are shot out of these miniature hand-grenades with considerable force, reach distances up to 12 metres (40 feet). That is why this remarkable plant has long been known by locals as the ‘squirting cucumber’.

Explosive know-how

The technology by which this plant manages to achieve this wide distribution of its seeds in such an original fashion is ingeniously simple, given the appropriate technical ‘know-how’.

The walls of these little ‘cucumbers’ (actually they are more properly called berries) are subjected to ever-increasing pressure as the fruit grows and ripens. The wall expands just enough to allow it to enlarge, but not too much, so as to allow for continuing build-up of pressure as the inside contents increase their volume. At maturity, the pressure inside the fruit is such that even casual brushing past by an animal can set off the ‘explosion’. Ripe fruits may even explode spontaneously.

Figure 1

Figure 2

What happens is this: the region where the stem attaches is the weakest point, and it separates there, leaving behind a circular hole. The instant this happens, all the built-up pressure inside this fruit is released at once, allowing a violent elastic contraction of its highly stretched walls. The contents are sprayed out in a multi-headed fountain through this hole where the stem used to be. Fig. 2 (at bottom) shows one of the fruits after its ‘explosion’—just a little drop of remaining fluid can be seen oozing out of the opening.

One can only safely cut into the fruit if it is still young and unripe. Fig. 1 shows such a specimen, cut lengthwise. In spite of its immaturity, in the uncut form it is already under considerable tension; when cut, it shrinks to half its diameter and the seeds are squeezed up to protrude from the cut surface.

No reason to shoot!

According to the pious dogma of the true evolutionist believer, all such marvellous mechanisms are the result of pure chance, shaped by the necessity of survival of the fittest. However, in the very same region, there are many other plants which are doing very nicely, thank you, without such a fancy way of spreading their seeds. Other plants are known that have various ingenious ways of ‘shooting’ their seeds. In each case they live surrounded by plants which don’t shoot, and which survive just as well, if not better. Think of the grasses, which as relative pacifists are much more successful in the same regions than any of these more militaristic plants. What justification is there for insisting that ‘survival of the fittest’ has been the major instrument in creating a mechanism which is clearly quite unnecessary for sheer survival, and in terms of quantities of plants is less fit than its neighbours?

Think also of the many features that have to be programmed to work just right in this little squirt-bomb. If the first mutational ‘attempt’ at such a mechanism did not have enough inner pressure, there would be no explosion. Thus, there would be no possible selective advantage for such a step to continue evolving in that direction. If the elasticity of the growing walls is not just right, no eruption will occur. If the timing of all these events is not programmed exactly right, so that it only happens after the seeds are ripe and not before, such a mechanism will blow itself into extinction.

Programmed

Not only the design, but the entire life history of the fruit is geared and programmed towards this one climactic event of self-propagation.

But words such as design and programmed are anathema to the central dogma of the evolutionist, as are words like plan and purpose, no matter how obvious. In spite of the fact that the evolutionists’ explanation is full of inherent difficulties and self-contradictions, their wishful dreams must be followed. Otherwise, they would risk losing their oh-so-comfortable faith in the ability of ‘chance and necessity’ to create all things.

(Translated and adapted by Dr Carl Wieland from Professor Kuhn’s book, Stolpersleine des Darwinismus (2) (Darwin’s Stumbling Blocks), factum-Taschenbuch Nr. 106, Forderung christlicher Publizistik, Switzerland, 1985. Used with permission.)

About the author

Dr Wolfgang Kuhn is professor of biology at the University of Saarbrucken. He has studied botany, zoology, geography, chemistry, and philosophy, and has lectured on these at several universities. Return to top.