Ecological Knowledge, Leadership, and the Evolution of Menopause in Killer Whales

@article{Brent2015EcologicalKL,
  title={Ecological Knowledge, Leadership, and the Evolution of Menopause in Killer Whales},
  author={Lauren J. N. Brent and Daniel W. Franks and Emma Foster and Kenneth C. Balcomb and Michael A. Cant and Darren P. Croft},
  journal={Current Biology},
  year={2015},
  volume={25},
  pages={746-750}
}
Classic life-history theory predicts that menopause should not occur because there should be no selection for survival after the cessation of reproduction [1]. Yet, human females routinely live 30 years after they have stopped reproducing [2]. Only two other species-killer whales (Orcinus orca) and short-finned pilot whales (Globicephala macrorhynchus) [3, 4]-have comparable postreproductive lifespans. In theory, menopause can evolve via inclusive fitness benefits [5, 6], but the mechanisms by… 
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