Corvids are exceptionally intelligent birds, and what Marzluff and Angell do in this book is look at the different sorts of behaviors and attitudes different corvids display, the ability to make tools or adapt, and discuss how their brains develop those reactions or insights.
Most chapters begin with an example of the type of behavior they want to discuss, then spend some time talking about which portions of the brain and nervous system would be involved. If there's been any field experiments or laboratory testing done, they'll discuss that. Then the chapter usually swings back around to a few more examples to use to drive the point home.
Like ravens learning a short stick can be used to retrieve a longer stick, then using this skill to get the proper tool to get some food. How does that work, what seem to be the limitations?
The authors did a study where they wore one type of mask while they captured and banded crows, and another type when they brought them food. Then they'd anesthetize them and do an imaging sequence to see which parts of the brain were showing recent activity. But once the crows were released back on campus, they or their students would occasionally walk around campus wearing one of the masks to see how the birds react. Apparently the captured crows regale their buddies will tales of their imprisonment, so even crows who weren't captured know to be on the lookout for that particular face.
The most interesting part of that was even in the mask was worn upside-down, the crows could still recognize it as the same face. Sometimes they would even turn their heads upside-down to make certain of it, then begin scolding.
The anecdotes and the field study parts interest me more than the neurological side, but they do provide an appendix with several cross-section diagrams of corvid brains to help illustrate what they're describing, which helps a little. Mostly it's fun to read about all these things crows, ravens, and jays do to thwart dangers, get food, or seemingly just to amuse themselves.
'Try calling a dog without moving your tongue or lips. Unless you are a ventriloquist, the dog is likely to look at you with a confused, pitiful expression. Yet talking crows mimic precisely the nuances of our speech simply by adjusting the muscles within their throats.'
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