Researchers say rare fossil evidence provides evidence of one type of evolution . 20 fossilized pterodactyls found in China in rock dating back 50 million years . They show creatures had one of two types of evolved pterodactyls . The fossils indicate Darwinopterus was about the size of a crow , with long jaws , sharp , pointed teeth and a flexible neck . Scientists say fossils show groups of features changed relatively rapidly .
Researchers say rare fossil evidence provides evidence of one type of evolution . 20 fossilized pterodactyls found in China in rock dating back 50 million years . They show creatures had one of two types of evolved pterodactyls . Scientists say fossils show groups of features changed relatively rapidly .