The sympathetic nervous system, which enables the fight-or-flight response, was thought to be present only in jawed vertebrates. Analysis of a jawless vertebrate suggests that this system might be a ...

Scientists have long puzzled over the gap in the fossil record that would explain the evolution of invertebrates to vertebrates. Vertebrates, including fishes, amphibians, reptiles, birds, mammals, ...

Dedication to William Buckland / Christopher J. Duffin -- Introduction. Vertebrate coprolite studies : status and prospectus / Adrian P. Hunt ... [et al.] -- History of study. The earliest published ...

The state fossil of Illinois is a strange creature with stalked eyes and a long nose-like appendage with teeth, dubbed the “Tully monster.” Specimens typically measure just 15 centimeters (about 6 ...