"Dog bites man" is not an unusual headline. However, "Man bites dog" would usually get people's attention. If that's true, the headline "Leeches teach physicians" should capture everyone's attention.
Physicians used leeches in bloodletting treatments well into the 19th century. They were used to treat everything from headaches to heart disease. As the 20th century matured, the medical use of leeches became not only a memory but a symbol of how backward medicine used to be. Now, as the 21st century is underway, leeches are again a part of modern medicine.
To obtain their food, leeches inject a powerful blood thinner called hirudin. This hirudin is what interests modern medical researchers in leeches. Doctors have for many years been using a blood thinner called heparin to dissolve blood clots, such as those associated with heart attacks. But researchers are finding that hirudin is ten times as effective as heparin in dissolving clots, and in addition it works directly to prevent clotting. The studies continue. However, medical researchers are convinced that the blood thinner which leeches taught them how to make offers a powerful medicine. Should the possibilities presented by this modern medicine be realized, many lives that are now lost due to blood clotting may soon be routinely saved.
The Creator of the heavens and Earth is so wise and generous that He can teach even modern science some new things through a seemingly simple creature like the leech.