Pseudoextinction

Pseudoextinction (or phyletic extinction) of a species occurs when all members of the species are extinct, but members of a daughter species remain alive. The term pseudoextinction refers to the evolution of a species into a new form, with the resultant disappearance of the ancestral form. Pseudoextinction results in the relationship between ancestor and descendant still existing even though the ancestor species no longer exists. The classic example is that of the dinosaurs. While the dinosaurs of the Mesozoic died out, their distant children, birds, live on today. As of now it is accepted that modern birds evolved from Archaeopteryx, a small dinosaur with flight feathers from the Mesozoic period. Many other families of bird-like dinosaurs also died out as the heirs of the dinosaurs continued to evolve, but because their birds continue to thrive in the world today these species are only pseudoextinct.