Gleiss, A.C., Potvin, J. and Goldbogen, J.A. (2017) Physical Trade-Offs Shape the Evolution of Buoyancy Control in Sharks. Proceedings of the Royal Society B: Biological Sciences, 284, Article ID: 20171345. https://doi.org/10.1098/rspb.2017.1345

has been cited by the following article:

• TITLE: Is the Shark Just Drifting, or Does It Take a Quick Nap?

  AUTHORS: Erich K. Ritter

  KEYWORDS: Drifting, Melatonin, Pineal Gland, Shark, Sleep

  JOURNAL NAME: Open Journal of Animal Sciences, Vol.10 No.1, December 13, 2019

  ABSTRACT: It is unknown if resting sharks can sleep, which is also true for gliding ones. Here, a videotaped bull shark is presented that drifted in an uncontrolled manner for 120 seconds while sinking with 0.1 m/second. Several aspects are discussed to determine if the shown behavior reflects the commonly accepted definition of sleep. Additionally, the idea is also discussed if this state might reflect a “quiet waking state” instead of where the shark still maintained some vigilance despite its general appearance.