A typical species becomes extinct within 10 million years of its first appearance, although some species, called living fossils, survive virtually unchanged for hundreds of millions of years.
(A typical species; becomes; extinct; T:within 10 million years of its first appearance) (some species; called; living fossils) (some species, called living fossils; survive virtually unchanged; )
A typical species some species some species, called living fossils
becomes called survive virtually unchanged
extinct T:within 10 million years of its first appearance
living fossils