Ravens, Corvus corax - Creatures of Intelligence
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The Cleverness Of Corvids
Ravens: Clear communicators, smart mimics - Adirondack Explorer
Birds In Halloween Folklore – Pet Birds by Lafeber Co.
Smarter than the average 4-year-old? Raven intelligence at heart
Ravens found able to remember people who tricked them up to two
How to Know the Birds: No. 2, Here's Looking At You, Crow « ABA Blog
Ravens have paranoid, abstract thoughts about other minds