Input (grade 13): This led scientists to recognize that Walcott had barely scratched the surface of information available in the Burgess Shale, and also made it clear that the organisms did not fit comfortably into modern groups.
Output (grade 8): This led scientists to recognize that Walcott had barely scratched the surface of information available in the Burgess Shale. It was clear that the organisms did not fit comfortably into modern groups.