List of common misconceptions
Mammals did not evolve from reptiles, just as humans have not evolved from chimpanzees (above). Soon after the first vertebrate land-dwellers appeared, they split into two branches. The line leading to mammals (Synapsids) diverged from the line leading to reptiles (Sauropsids) about 320 million years ago, in the mid Carboniferous period. Only much later did the modern reptilian groups (lepidosaurs, turtles and crocodiles) emerge. Mammals are the only survivors of the synapsid line. The confusion over the origin of mammals comes from conflicting definitions of "Reptile". Under Linnaean taxonomy reptiles are all amniotes except mammals and birds, thus including the synapsids as well as the first basal amniotes. With the rise of classification based on phylogeny, the Sauropsida excludes basal amniotes and the synapsid line. The synapsids are popularly known as "mammal-like reptiles". An example is Dimetrodon, which is often thought of as a dinosaur, but is in fact neither a dinosaur nor closely related to modern reptiles.