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Observations of a galaxy from an early period of the Universe’s history reveal a bar-shaped structure and gas dynamics thought not to have been possible at that time. In broad brushstrokes, galaxies ...

The molecular clock theory posits that genetic changes happen steadily and gradually, offering a reliable means for peering into the past and theorizing when complex life first emerged. However, there ...

"Despite the ongoing cultural controversy in America, evolution remains a cornerstone of science. In this book, Francisco J. Ayala---an evolutionary biologist, member of the National Academy of ...

One important use of questioning is to facilitate student thinking about and discussion of science. Asking the right question at the right time can help a student clarify his or her thoughts, ...