Shop Windows to the Universe

Dig into Montana Before History: 11K Years of Hunter-Gatherers in the Rockies and Plains by D. H. MacDonald, Ph.D. See our online store book collection.
This is an image of ducks - lifeforms on Earth.
Click on image for full size
Perfect Vision Graphics

Life on Earth

The Earth is very unique to our universe because it is the only planet known to have life . Our planet is the right distance from the sun so that it is possible for animals and plants to live. The first signs of life were blue-green algae and bacteria formed in the seas, and they did not appear until 3.5 billion years ago. More complex plants and animals did not develop until 570 million years ago. There are about 1.3 million species of animals on Earth today and probably millions more that are unknown.


Shop Windows to the Universe Science Store!

"Ready, Set, SCIENCE!: Putting Research to Work in K-8 Science Classrooms", from the National Research Council, provides insight on the types of instructional experiences help K-8 students learn science with understanding. Check our other books in our online store.

Windows to the Universe Community

News

Opportunities

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Can there be Life in the Environment of Jupiter?

Jupiter's atmospheric environment is one of powerful winds, going 250 miles per hour, and temperatures from -270 degrees to +32 degrees (freezing temperature). These winds make it hard for life forms to...more

The possible discovery of Life on Mars

In July, 1996 a team of scientists said that they had discovered possible fossils of bacteria in a meteorite named ALH84001 that came from Mars. It was found in Antarctica in 1984 after having landed there...more

The Environment of Saturn

Saturn's atmospheric environment is one of powerful winds, going 250 miles per hour, and temperatures from -270 degrees to +80 degrees. With winds like these, it is hard to have peace and quiet. The region...more

Can there be Life in the Environment of Titan?

The air of Titan is a lot like the Earth's, except that it is very cold, from -330 degrees to -290 degrees! Like the Earth, there is a lot of Nitrogen and other complex molecules. There also may be an...more

Autotrophs

Organisms that are able to "make their own food" are called autotrophs, meaning "self-feeders". Some examples of autotrophs are plants and algae (shown in the picture). Both plants and algae use photosynthesis...more

Coacervates

In the warm early ocean, large molecules came together into a form called *coacervates*. Molecules such as these will form coacervates in the same way that beads of vinegar in oil come together. These...more

Early Life

Over a very long time, gradual changes in the earliest cells gave rise to new life forms. These new cells were very different from earlier cells because they were able to get their energy from a different...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part by the National Science Foundation and NASA, our Founding Partners (the American Geophysical Union and American Geosciences Institute) as well as through Institutional, Contributing, and Affiliate Partners, individual memberships and generous donors. Thank you for your support! NASA AGU AGI NSF