Evolution of high duty cycle echolocation in bats

@article{Fenton2012EvolutionOH,
  title={Evolution of high duty cycle echolocation in bats},
  author={M. Brock Fenton and Paul A. Faure and John M Ratcliffe},
  journal={Journal of Experimental Biology},
  year={2012},
  volume={215},
  pages={2935 - 2944}
}
Summary Duty cycle describes the relative ‘on time’ of a periodic signal. In bats, we argue that high duty cycle (HDC) echolocation was selected for and evolved from low duty cycle (LDC) echolocation because increasing call duty cycle enhanced the ability of echolocating bats to detect, lock onto and track fluttering insects. Most echolocators (most bats and all birds and odontocete cetaceans) use LDC echolocation, separating pulse and echo in time to avoid forward masking. They emit short… 
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TLDR
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