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Cetaceans Have Complex Brains for Complex Cognition

  • Lori Marino mail,

    To whom correspondence should be addressed. E-mail:

  • Richard C Connor,
  • R. Ewan Fordyce,
  • Louis M Herman,
  • Patrick R Hof,
  • Louis Lefebvre,
  • David Lusseau,
  • Brenda McCowan,
  • Esther A Nimchinsky,
  • Adam A Pack,
  • Luke Rendell,
  • Joy S Reidenberg,
  • Diana Reiss,
  • Mark D Uhen,
  • Estel Van der Gucht,
  • Hal Whitehead
  • Published: May 15, 2007
  • DOI: 10.1371/journal.pbio.0050139

Reader Comments (4)

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elephants are right up there with dolphins, too

Posted by plosbiology on 07 May 2009 at 22:21 GMT

Author: jess marin
Position: author
Submitted Date: November 08, 2007
Published Date: November 9, 2007
This comment was originally posted as a “Reader Response” on the publication date indicated above. All Reader Responses are now available as comments.

"Dolphins are the only mammal, other than humans, shown capable of extensive and rich vocal and behavioral mimicry."

What about elephants? Kosik the Asian elephant can mimic a human voice and elephants have demonstrated the ability to mimic movement, as well.

Elephants brains are more complex than humans and apes and their hippocampus, which processes emotion as well as memory is larger than that of any dolphin, ape, or human. So where do elephants fit in compared with dolphins? Emotional richness is one of the things we class as being highly intelligent, so wouldn't elephants surpass every other species, including humans on this one?

Also, you state dolphins can recognize themselves in a mirror. So, that includes all 38 species? It would be more accurate to say "Bottlenose dolphins are self aware" as dolphins is a very broad group who range hugely in intelligence.

No competing interests declared.