Evolution and obesity: Resistance of obese-prone rats to a challenge of food restriction and wheel running

W. D. Pierce, Abdoulaye Diane, C. D. Heth, J. C. Russell, S. D. Proctor

Research output: Contribution to journalArticle

9 Citations (Scopus)


The adaptive hypothesis that an obese-prone genotype confers a fitness advantage when challenged with food restriction and food-related locomotion was tested using a rat model. Juvenile (35-40 days) and adolescent (45-50 days) JCR:LA-cp rats, obese prone (cp/cp) and lean prone (/?), were exposed to 1.5 h daily meals and 22.5 h of voluntary wheel running, a procedure that normally leads to self-starvation. Genotype had a dramatic effect on survival of rats when exposed to the challenge of food restriction and wheel running. Although similar in initial body weight, obese-prone juveniles survived twice as long, and ran three times as far, as their lean-prone counterparts. Biochemical measures indicated that young obese-prone animals maintained blood glucose and fat mass, whereas lean-prone rats depleted these energy reserves. Corticosterone concentration indicated that obese-prone juveniles exhibited a lower stress response to the survival challenge than lean-prone rats, possibly due to lower energy demands and greater energy reserves. Collectively, the findings support the hypothesis that an obese-prone genotype provides a fitness advantage when food supply is inadequate, but is deleterious during periods of food surfeit, such as the energy-rich food environment of prosperous and developing societies worldwide.

Original languageEnglish
Pages (from-to)589-592
Number of pages4
JournalInternational Journal of Obesity
Issue number3
Publication statusPublished - 1 Mar 2010
Externally publishedYes



  • Adaptation
  • Food restriction
  • Genotype
  • Survival
  • Wheel running

ASJC Scopus subject areas

  • Medicine (miscellaneous)
  • Nutrition and Dietetics
  • Endocrinology, Diabetes and Metabolism
  • Medicine(all)

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