posted on Jul, 10 2003 @ 11:29 PM
The primitive horseshoe crab lived on the Earth 250 million years ago, and is still with us today. Now scientists think they can use its blood to
detect life on other planets. When a horseshoe crab is injured, its blood, which is the color blue, clots in order to keep infection out. "One of the
reasons the horseshoe crab has survived for so long is its advanced immune system," says biologist Norman Wainwright. "This system can be used to
find microbial life." Scientists have put the crab's blood enzymes into a hand-held instrument that can test for signs of life.
"If there are microbial species that evolved outside the Earth, that life may have originated here and spread throughout the solar system," says
Wainwright. "It's possible the cell walls of microbes on other planets may be similar enough to detect using the test."
The clotting enzymes are extracted from the blood and freeze dried. When inserted into the instrument, they cause a clear solution to turn bright
yellow when it encounters microbes. "The more yellow the sample, the more microbes it's finding," Wainwright says.