Far-Out Theory Ties SARS Origins to Comet  Stefan Lovgren for
National Geographic News June 3, 2003       Independent
Evolution       Gerberding said SARS is most explainable by
natural evolution of coronaviruses, either from an animal or a
poultry source, or possibly a coronavirus that's evolved in a
human. "We have many hypotheses that are far more plausible than
meteorites," she said.  Collecting Bacteria  About 100 tons (90
metric tons) of comet debris reach the Earth on a daily basis,
and Wickramasinghe says there is evidence for life arriving with
this debris.  In an experiment two years ago, he and scientists
from the Bangalore-based Indian Space Research Organization sent
sterile collecting devices into space and brought back large
quantities of microorganisms in samples of stratospheric air
captured at an altitude of 26 miles (41 kilometers). The
researchers were able to culture, or grow, two types of
microorganisms, which proved similar to known terrestrial
species.  "Our findings lend support to th