The second category of flightless birds is "huge, awful and terrifying." See the Ostrich and the Cassowary. They're the kind of birds that can look you in the eye before injuring you in some unspeakable way. As scary as these living monsters are though, their prehistoric ancestors were even worse!
Behold the Phorusrhacidae, giant predator birds from 20 million years in the past, more accurately and colloquially known as "terror birds".
A selection of terror birds, with an outline of a doomed man for scale. A - Brontornis burmeisteri; B - Paraphysornis brasiliensis; C - Phorusrhacos longissimus; D - Andalgalornis steuletti; E - Psilopterus bachmanni; F - Psilopterus lemoinei; G - Procariama simplex; H - Mesembriornis milneedwardsi and the silhouette of a man (1.75 m high) for scale (Herculano M.F. Alvarenga)
The largest species pictured here, Brontornis burmeisteri was 9 feet tall and weighed 800 pounds. Their size wasn't the scariest part of these monsters though. Their massive hooked beak (like a bald eagle's) gave them some pretty amazing eating abilities:
"An ostrich, the largest living bird, can swallow an apple. But a phorusrhacid could swallow a medium-sized dog in one gulp"- Herculano Alvarenga, a terror-bird expert
Scientists also estimate that these guys could run as fast as 30 miles per hour. That's enough to outrun a human (we go about 28)!
I'm very glad that these feathered fiends are relegated to the distant past. It's sad though that awesome and adorable flightless parrots seemed destined to meet the same fate. But at least they have a legitimate excuse, what with being slow, chubby, and tiny vegetarians and all.
Outline man waves to show his approval for a much more favorable modeling partnerAlso, PS, I think I wanna buy this shirt now.