The passenger pigeon lacked this spot. When rising in flight, the mourning dove makes a whistling sound with its wings, whereas the passenger pigeon did not. The juveniles-of the mourning dove and ...

The passenger pigeon was once the most numerous bird in the world ... Many people described the incredible, deafening sound of these. In fact, their numbers were said to be so great that large ...

Now, sadly, they are extinct. On September 1, 1914, Martha, the passenger pigeon, was found dead on the floor of her cage at the Cincinnati Zoo. She was the last surviving member of her species.