Crows vs. ravens

Both have a feather coat made up of various shades of gray and black. So it's hard to tell the difference between a raven and a crow - at least by their looks. But use your ears! It’s 'caw' vs. 'croak', as bird-experts from the renowned Cornell Lab of Ornithology (Lab of O) explain.

Can you hear the difference?

In fact, both animals have far more in common than sets them apart. Ravens and crows both belong to the family of corvids, which are famous for their intelligence.

They can recognize themselves in a mirror, build tools to reach out for food and have a very good memory. Sometimes, they can be quite resentful, which lead one researcher to declare: #link:http://www.ted.com/talks/joshua_klein_on_the_intelligence_of_crows:"Better don't piss them off."#

Now, that's some piece of good advice, because: they are everywhere. Or at least wherever humans are. They are what is called a 'synanthropic' species - which means they are well adapted to human environments. A fact that is quite fascinating given that other species are driven out by expanding cities.