The term 'ostriches, e.g.' is referring to a group of birds known as RATITES. RATITES are flightless birds that have a flat breastbone and are unable to fly. This group includes the ostrich, emu, rhea, cassowary, and kiwi. These birds are found in many parts of the world, including Africa, Australia, and New Zealand. They are the largest living birds and can reach up to 9 feet tall and weigh up to 300 pounds.