I picked up this book because I am somewhat obsessed with cephalapods. I am convinced they are going to inherit the earth after we're gone which is going to be sooner that we expect judging by the way things are going. My posts on China Mieville's novel with the same title and Jeff VanderMeer's novella King Squid might validate the fact that this isn't merely hyperbole. The book is interesting for the most part but not stuffed with as much bizarre trivia as I'd thought there would be. It's curious how squid, cuttlefish and octopus are intelligent but in a different way than humans and mammals in general. Their anatomy compels them to think differently and solve problems in ways that we find otherworldly.
"A squid ... lives in a three-dimensional world with boundaries set by temperature, light, oxygen, and salinity rather than physical objects. They do not have permanent laces of residence and are nomadic hunters. They eat mesopelagic (mid-level ocean) organisms that most people don't even know about. In short, they are are life-form quite alien to us, and so I think we tend to think of them as being less advanced or intelligent. Again, I think that attitude reflects our limitations of perception and understanding."
However, I found the discussion about nerve research which was sparked by a study of the squid axon quite boring. I also think that Williams should have included more on human interaction with squid throughout ages, real and imagined to make this work a more compelling read. And I don't think it would have necessarily diluted the science in the book.