Benchmark 5F
The Living Environment: Evolution of Life
Grades 3-5, page 123

Fossils can be compared to one another and to living organisms according to their similarities and differences. Some organisms that lived long ago are similar to existing organisms, but some are quite different.

NSES Content Standard D
Earth and Space Science: Properties of Earth materials
Grades K-4, page 134
Fossils provide evidence about the plants and animals that lived long ago and nature of the environment at that time.

NSES Content Standard C
Life Science: Diversity and adaptations of organisms
Grades 5-8, page 158
Extinction of a species occurs when the environment changes and the adaptive characteristics of a species are insufficient to allow survival. Fossils indicate that many organisms that lived long ago are extinct. Extinction of species is common; most of the species that have lived on the earth no longer exist.