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Young Voices for the Planet DVD in our online store includes 8 films where students speak out and take action on climate change.

Evidence of Evolution

The evolution of dogs is described in this evolutionary tree. Time is represented horizontally on the tree. Dogs that are more closely related, like domestic dogs and gray wolves, are closer on the tree. Scientists at the University of California developed this evolutionary tree based on fossil evidence, comparison of modern dogs, and genetic analysis of DNA and proteins.
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National Biological Information Infrastructure

Molecular Evolution

Molecular evolution is the process of how genes in populations of organisms change over time. Techniques to explore genes and chromosomes, such as electrophoresis and DNA and RNA sequencing, allow scientists to compare DNA from different species and figure out evolutionary relationships. Species that have very similar genetic-makeup have a closer evolutionarily relationship.

All living things have DNA. There are differences in DNA of individuals of the same species. There are many more differences in DNA of different species. To deduce evolutionary relationships using DNA, scientists compare the DNA of different species. Species that are very distantly related, such as turtles and bacteria, have different DNA. Species that are more closely related have more similarities in their DNA. For example, 98.7% of human and chimpanzee DNA is the same, indicating a relatively close evolutionary relationship.

Last modified May 16, 2005 by Lisa Gardiner.

Shop Windows to the Universe Science Store!

Our online store includes issues of NESTA's quarterly journal, The Earth Scientist, full of classroom activities on different topics in Earth and space science, ranging from seismology, rocks and minerals, oceanography, and Earth system science to astronomy!

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Cool It! Game

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ExploraTour - Looking at the World in a Different Light

Look at the bed below the body of the sleeping man. You can still see where he was lying down. The heat from his body warmed up the bed sheets which are now radiating infrared light toward your eyes....more

ExploraTour - Looking at the World in a Different Light

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ExploraTour - Looking at the World in a Different Light

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ExploraTour - Looking at the World in a Different Light

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ExploraTour - Looking at the World in a Different Light

This is a volcano on the island of Miyake in Japan. It has erupted, sending hot lava and ash into the air, a total of ten times. The time after one eruption until the next occurred was about twenty years...more

ExploraTour - Looking at the World in a Different Light

This is a picture of a galaxy in visible light. A galaxy is a large number of stars, some like our sun, some bigger, some smaller and all moving together through space. This galaxy is called Centaurus...more

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This is a plant in Gary, Indiana where power is made. We use power to run things like television sets, radios, lights, and microwave ovens. The picture looks very strange because it was taken in infrared....more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA