Shows how the gradual changes in a pond affect living things from the end of winter to the beginning of summer. Includes extreme close-ups and photomicrography to show protozoa and other minute forms of life found in a pond.
1998
2019
1953
2013
1983
2004
2008
2001
2014
2011
2007
2010
1985
2005
1984
2017
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2021
1980