Photograph of a cast of an Archaeopteryx fossil.

Evolution, or descent with modification, is the unifying concept of the biological sciences and explains life's past and present biodiversity. This part of Earth@Home is focused on the science of evolution and is currently under active development and expansion. Current and planned resources include introductory information, as well as detailed overviews of the evolution of particular groups (for example, grasses). Check back soon for new additions.

Introduction to Evolution

What is biological evolution and why does it matter?

Composite image of the face of a marble statue of Charles Darwin superimposed over a page from one of Darwin's notebooks showing a sketch of an evolutionary tree.

Evolution of Grasses

An overview of grasses, including their biology, diversity, genetics, domestication, and significance to human society, with a special emphasis on grasses in Tribe Andropongoneae, commonly known as the Bluestem Tribe or the Sorghum Tribe.

Photograph of cogongrass. The photo shows a large field of tall, green grasses with feathery while inflorescences.

Essays about Evolution

Written by PRI staff members.

Photograph of the fossil Tiktaalik.