A shrewd tweak
The chairs were rickety. So I rummaged around the kitchen drawer, extracted an old knife and used its tip to drive a few screws back into the wood. The knife kept on losing grip and I kept on swearing. The fastest and least infuriating way to have done the job would have been to go down to the cellar and find a screwdriver. Both utensils can be used to drive in screws, but one has been intentionally manufactured to perform just that, simultaneously reducing the time and energy involved. Nature, too, has its screwdrivers. Given time and chance, it will always take the opportunity to select a commodity which will make things, if not easier, at least more in tune with what is needed. One example: ribosomes are huge molecular complexes whose role is to synthesize proteins in cells. Until recently, it was thought that all ribosomes were alike. A bit like kitchen knives. However, it turns out that some ribosomes differ slightly in their makeup and are found only in certain kinds of cell - presumably because they synthesize proteins particular to these cells. One such ribosome has been discovered in sperm cells, along with a protein known as large ribosomal subunit protein eL39-like*, or RPL39L.