Can Fish Count?: What Animals Reveal About Our Uniquely Mathematical Minds

Counting is far more complex than it may seem, according to this savvy survey from cognitive neuropsychology professor Butterworth (Dyscalculia). He begins by positing that humans have “an innate capacity to count,” even though some cultures don’t make use of actual counting words, and backs up the claim with research he and his colleagues have performed to study children’s relationship to counting. He also offers data indicating that Stone Age humans used counting words and that Neanderthals and Homo erectus “recorded counts on bones, stones and cave walls.” Butterworth then moves on to explore the abilities of an array of animals to use math: some chimps have “solved the travelling salesman problem,” while birds have proven to be as mathematically astute as a seven-year-old child, female Túngara frogs count male call notes, and fish have demonstrated an ability to identify and pick larger numbers, especially when they calculate in pairs. In the end, Butterworth writes, the ability to perform mathematical calculations extends very far back in the evolution of life, and a basic sense of numeracy is an evolutionary advantage leading to enhanced reproduction, food gathering, and predator avoidance. Though occasionally the writing can be long-winded and jargony, the plentiful real-world examples are always enlightening and entertaining. Math-minded readers will find this a fun ride. (Apr.)