Thursday, 10 March 2022

Snoozing Sharks?

It used to be assumed that sharks didn't sleep. It was argued they couldn't sleep, as they needed to constantly move forward to aerate their gills. There has, however, been anecdotal evidence, largely from scuba divers, that some sharks do sleep. A La Trobe University (Australia) study has now produced scientific evidence that at least some shark species have regular snooze (https://www.theguardian.com/environment/2022/mar/10/sleeping-with-fishes-australian-scientists-discover-some-sharks-do-need-their-shut-eye). The La Trobe study looked at a benthic (bottom-living) species, the Draughtboard shark. Monitoring this fish's metabolism and posture, clearly revealed bouts of sleeping. There is no reason to suspect that this phenomenon doesn't also occur in more active pelargic species.
-

No comments:

Post a Comment

Subscribe to: Post Comments (Atom)

Seeing the Changes 2176

  In Bynea, Square-stalked St Johns wort ( Hypericum tetrapterum ); Butterfly bush ( Buddleja davidii ) and Scentless mayweed ( Matricaria p...

  • Charging Electric Vehicles (For Road Use)
    It's necessary, where possible, to replace diesel and petrol-fueled vehicles by electrical equivalents. Electric vehicles (EVs) don...
  • Stepping On the Gas?
      It should hardly be called a study. A  Which comparison looked at levels of nitrogen dioxide and small particulates (PM 2.5s) in 5  Londo...
  • Gridlock in European Cities
      Europe has a city congestion problem. In 2023, London was the most gridlocked location, closely followed by Paris and Dublin. In that year...