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
Largest prehistoric animals size. Total length was probably up to in female and they weighed about . The largest extinct "Titanohierax" was a giant hawk about 8 kilograms that lived in the Antilles, where it was among the top predators. The largest-known in this group was a giant flightless "Sylviornis", a bird long and weighing up to about . The largest-known songbird is the extinct giant grosbeak ("Chloridops regiskongi") at long. The largest-known cormorant was the spectacled cormorant of the North Pacific ("Phalacrocorax perspicillatus"), which became extinct around 1850, was larger still, averaging around and . The largest-known in this group—which has been