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


Evolution is the process of change through time. Many things evolve. Language evolves so that English spoken four hundred years ago during the time of playwright Shakespeare was very different than English spoken today. Technology evolves over time as new things are invented and modified. Scientific theories evolve as more data are collected and analyses are done. Life evolves over very long timescales as species change over many, many generations. This is called biological evolution. Evolution is the foundation for the modern sciences of paleontology (the study of fossils and the history of life), ecology (the study of ecosystems), and biology (the study of life) including medical science.

The links below hightlight resources on Windows to the Universe that are about biological evolution and related topics.

Evidence of Evolution

The Evidence of Evolution Exploratour examines the scientific evidence of biological evolution. Take the tour to travel through 10 web pages about the scientific theory that explains how and why living things change over many generations. Take the whole tour or explore individual topics listed below. Topics include:

Evolution in the News

Podcasts about Evolution

  • Evolution Revolution - A new study suggests human evolution has been supercharged the past 40,000 years. (1 min. 30 sec.) from NSF
  • Distant Whaletive - A research team has discovered the missing link between whales and their four-footed ancestors. (1 min. 30 sec.) from NSF
  • Got Mica? - Earth's first life may have formed inside a primordial soup that was sandwiched between the many layers of the mineral mica. (1 min. 30 sec.) from NSF


Scientists who Researched Evolution

  • Charles Darwin was the first scientist to publish a comprehensive theory of evolution in the19th century.
  • Stephen Jay Gould expanded Darwin's theory with his own concept of punctuated equilibrium in the 20th century.
  • Leonardo da Vinci did a little bit of everything! When he was not painting the Mona Lisa, he was a scientist and discovered how sedimentary rocks and fossils are formed.

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Last modified October 15, 2011 by Jennifer Bergman.

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