Input (grade 13): The group has hardly changed in millions of years; the modern horseshoe crabs look almost identical to prehistoric genera such as the Jurassic Mesolimulus, and are considered to be living fossils.
Output (grade 8): The group has hardly changed in millions of years. The modern horseshoe crabs look almost identical to prehistoric genera such as the Jurassic Mesolimulus, and are considered to be living fossils.