Largest organisms were related to the ostrich. They exceeded in height and . The last of the elephant birds became extinct about 300 years ago. Of almost exactly the same upper proportions as the largest elephant birds was "Dromornis stirtoni" of Australia, part of a 26,000-year-old group called mihirungs of the family Dromornithidae. The largest carnivorous bird was "Brontornis", an extinct flightless bird from South America which reached a weight of and a height of about . The tallest carnivorous bird was "Kelenken", which could reach 3 to 3.2 meters in height and 220 to 250 kilograms. The tallest bird ever was
White-collared swift White-collared swift The white-collared swift ("Streptoprocne zonaris") is a resident breeding bird from central Mexico, the Greater Antilles and Trinidad south to Peru, northern Argentina and southeastern Brazil. This very large swift builds a saucer nest of mud, moss and chitin on a ledge in a cave, usually behind a waterfall, and lays two white eggs between March and July. It breeds in the mountains and foothills, but forages over a much larger area, including lowlands. White-collared swift is a massive and powerful species, long, and weighing . It is the largest species of swift in its range except in