Was It Designed?

The Ovipositor of the Wood-Boring Wasp

● The female wood-boring wasp deposits its eggs inside pine trees, and its method of doing so has inspired scientists to develop safer and more-efficient surgical probes.

Consider: The wood wasp burrows into the pine tree by means of an ovipositor​—a needlelike tube with two interlocking shafts, or “valves,” each of which is covered with backward-facing teeth. The teeth of one valve catch onto the wood, thus providing resistance, while the other valve slides a small step forward. Then the teeth of that valve catch onto the wood, providing resistance, while the first valve slides forward. By means of rapid oscillation​—during which the valves alternate in providing resistance and moving forward—​the ovipositor drills nearly an inch (up to 20 mm) into sapwood with minimal force, neither buckling nor breaking in the process.

Inspired by the ovipositor of the female wood wasp, scientists have created a prototype neurosurgical probe that operates on a similar principle. Its silicon needle consists of two oscillating valves, each with microsize teeth that can penetrate areas deep in the brain with minimal damage. However, the instrument is to have an additional feature. “Unlike existing rigid surgical probes,” explains New Scientist magazine, “the device will be flexible enough to move along the safest possible route, bypassing high-risk areas of the brain during surgery, for example.” Such a probe would also reduce the number of incisions needed to access hard-to-reach areas.

What do you think? Did the ovipositor of the female wood-boring wasp come about by chance? Or was it designed?

[Diagram on page 25]

(For fully formatted text, see publication)

While one valve pushes down and cuts into the wood, the other valve pulls up and its teeth provide resistance


Alternating forces

[Picture Credit Lines on page 25]

Wasp: David R. Lance, USDA APHIS PPQ, Bugwood.org; diagram: J. F. V. Vincent and M. J. King, (1996). The mechanism of drilling by wood wasp ovipositors. Biomimetics, 3: 187-201