Hoatzin.

The Hoatzin of Northern S. America is a fun one for scientists.
People aren't really sure what these are related to, but they seem archaic in morphology which, if true, is a good glimpse of the evolution of some other living birds.

As both large and distinguished birds, its a surprise they are not threatened (good!) nor does it seem likely that they will be. Though many in the area eat larger birds or use feathers for various purposes, the Hoatzin is not ideal for it. Why? They smell terrible and apparently their eggs are revolting. So people only eat it when ABSOLUTELY necessary. Also, they live in mangrove and riparian forest systems -- significantly less threatened than other types of forests in Brazil.

Something interesting about them is they are born with a claw at the end of their wings. They are known to be clumsy, and these claws come in handy when young. Growing up in mangroves is not a safe environment -- all sorts of things wanting to eat chicks might show up, so to counteract bad balance, they can use their claws to climb onto branches or hang on for dear life.