1. Species:
- Passenger pigeon (Ectopistes migratorius): The passenger pigeon was a North American bird that was once incredibly abundant but went extinct in the early 20th century due to overhunting and habitat loss.
- Homing pigeon (Columba livia domestica): The homing pigeon is a domesticated breed of the rock dove, known for its remarkable ability to find its way back to its home loft from great distances.
2. Physical Appearance:
- Passenger pigeon: The passenger pigeon was a medium-sized bird, slightly smaller than a mourning dove. It had a bluish-gray head and neck, a grayish-brown back, and a long pointed tail. The male had a reddish-brown breast, while the female's breast was duller.
- Homing pigeon: The homing pigeon is a robust bird with a muscular build. It typically has various color variations, including blue, black, white, and mixed patterns. They have distinctive wing markings known as "checkerings" on the wings.
3. Behavior and Habitat:
- Passenger pigeon: The passenger pigeon was a highly social bird that lived in enormous flocks, numbering in the billions. They were nomadic, moving across North America in search of food, mainly acorns and beechnuts.
- Homing pigeon: The homing pigeon is known for its exceptional homing instinct, which allows it to find its way back to its loft from long distances. It is trained to carry messages and was historically used for communication before modern technology. They are commonly kept as pets and used in racing competitions.
4. Conservation Status:
- Passenger pigeon: The passenger pigeon is extinct due to uncontrolled hunting and habitat destruction. The last known passenger pigeon, named Martha, died in 1914 in the Cincinnati Zoo.
- Homing pigeon: The homing pigeon is a domesticated breed and not considered endangered or threatened.
In summary, while passenger pigeons were once abundant but became extinct due to human actions, homing pigeons are domesticated birds known for their unique homing ability and are still present worldwide as pets and in specialized uses like racing.