Standing the test of time. Standing the Test of Time Two proteins found in horseshoe crab's blood may reveal some of nature's oldest and most basic strategies in the battle against invading microbes.
Nature is loathe to let go of good ideas.
Biologists know that if they find an interesting molecule in one type of animal, they may learn something about that animal. But if they find the same molecule in a variety of distantly related animals, they may learn something about life itself. Invertebrates have a less complex, poorly understood, but nonetheless effective strategy for recognizing and destroying disease-causing pathogens. Without antibody-based immune systems, many invertebrates manage to live long and healthy lives. Clams and mussels are thought to live as long as 90 years.