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Science, Evolution, and Creationism, by the National Academies, focuses on teaching evolution in today's classrooms. Check out the other publications in our online store.

Kingdom Animalia

With over 2 million different kinds of animals, Kingdom Animalia is the largest of the kingdoms. But when you think of an "animal", what image comes to mind? While animals like bears, fish, and birds are the most familiar to us, over half of all the animals on Earth belong to a group of animals known as "arthropods". Arthropods include animals such as centipedes, crabs, insects, and spiders. This means that the majority of animals come from a group of critters that give most folks the creeps!

So, what exactly is an "animal"? With so many different kinds of animals, it's hard to imagine what they all might have in common. First, animals are "multicellular". This means they are made of many cells, unlike bacteria, which are made of only one cell. Second, all animals must get their food by eating other organisms, such as plants, fungi, and other animals. Plants don't have to eat other organisms because they can use the Sun's energy to make their own food. In addition, all animals need oxygen to survive. Did you know that fish can breathe oxygen from the water that passes through their gills and earthworms get their oxygen through their skin?

Last modified October 15, 2011 by Jennifer Bergman.

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Traveling Nitrogen is a fun group game appropriate for the classroom. Players follow nitrogen atoms through living and nonliving parts of the nitrogen cycle. For grades 5-9.

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Traveling Nitrogen Classroom Activity Kit

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Kingdom Plantae

Kingdom Plantae has almost 300,000 different kinds of plants. Plants are found all over planet Earth. They can live in fields, in swamps, in oceans and in the desert. They can live where it is hot and...more

Exploratour - Life on Earth

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Biomes and Ecosystems

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Explore the Wetlands of Brazil!

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Kingdom Protista

Members of the Kingdom Protista are an unusual group of organisms that were put together because they don't really seem to belong to any other group. Some protists look or act like plants, others look...more

The Elements of Life

Elements make up everything around us including the trees of a forest, your pets, and even YOU! All living things are made up of small compartments called cells and the cells of every creature are made...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