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Why doesn't cancer risk simply scale with animal size?

A larger animal has more cells in which cancer might begin. That makes comparisons between species an interesting test of a simple prediction. Researchers investigate cancer deaths, longevity, and body size together, while asking how the available records shape what can be concluded.

5–7 min

Questions you could explore

  • Why is comparing species different from comparing individuals within one species?
  • What might zoo records reveal or leave out?

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