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5 Food Acquisition, Processing, and Digestion It is a classic moment from a TV nature show: a cheetah pursues a fleeing gazelle. The cheetah’s sensory, neural, and muscular systems work at full capacity in support of this unfolding drama. For some predators, however, the real drama begins after consumption. | iiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiiii Part II Processing Herbivory and Storage TcfottiJir Illllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllllll 5 Food Acquisition Processing and Digestion Christopher J. Whelan and Kenneth A. Schmidt 5.1 Prologue It is a classic moment from a TV nature show a cheetah pursues a fleeing gazelle. The cheetah s sensory neural and muscular systems work at full capacity in support of this unfolding drama. For some predators however the real drama begins after consumption. Burmese pythons Python molurus bivittatus live in a world of feast and famine going days or even weeks between meals that can be 60 larger than the python s body. As the snake digests these enormous meals its metabolic rate can increase forty-four-fold. A python digesting quietly on the forest floor has the metabolic rate of a thoroughbred in a dead heat. Metabolic upregulation is just the beginning intestinal mucosal mass total microvillus length and the mass of the heart and kidney all increase to keep up with the demands of the snake s digestive upheaval. After the snake assimilates its meal the whole system shifts into reverse. In a prodigious display of physiological flexibility everything returns to its semi-quiescent between-meal state. Feast-and-famine feeders like the python show the greatest range of gut regulation but virtually all foragers can regulate their guts to some extent. Typically the magnitude of this regulation matches the variation in the forager s diet. .
