The Mathematical Association of America has published an ebook written by James L. Cornette, Emeritus Professor of Mathematics, and Ralph A. Ackerman, Professor of Ecology, Evolution and Organismal Biology.
Calculus for the Life Sciences: A Modeling Approach is a calculus and differential equations text for first and second year university students built on numerous examples and data sets from the life sciences. The text begins with difference equation models whose solutions require only arithmetic, progresses through the topics of calculus citing life sciences differential equation models suitable to each topic, and concludes with systems of pairs of differential equations that model predator-prey, competition, and symbiosis between species.
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