Unit 4 — Dating Planet Earth

Science — Third Preparatory

1.8 Summary of Lesson 1

Fossils are remains or traces of ancient organisms, formed by rapid burial in sediments, ice, tar or amber.
Types body, trace, mold, cast and petrified.
The fossil record shows the order of appearance of life, mass extinctions, evolutionary relationships and ancient climates.
Diversity arises through adaptation, natural selection, mutation and geographical isolation.
Comparative anatomy homologous (same structure, common ancestry) and analogous (same function, different structure); transitional fossils like Archaeopteryx.

Unit 4 — Dating Planet Earth · 9 / 28