These terrifying (and wacky) birds ruled Earth after the dinosaurs

Key Points:

• Around 66 million years ago, a massive asteroid impact caused a mass extinction that wiped out 75% of species, including most dinosaurs, except for birds which later evolved into diverse forms filling ecological niches left by extinct dinosaurs.
• Terror birds, large flightless predators up to 3m tall and 350kg, dominated South America for over 40 million years but went extinct about 100,000 years ago, with their closest living relatives being the seriemas.
• Elephant birds of Madagascar were massive herbivores up to 3m tall and 730kg, laying the largest eggs ever recorded; they went extinct around 900 years ago due to human impact but are closely related to New Zealand’s kiwis.
• Australia’s demon ducks, or dromornithids, were huge herbivores weighing up to 725kg, surviving for over 35 million years before human predation led to their extinction within a few thousand years.
• Other notable extinct birds include Europe’s Gastornis and North America’s Diatryma, once thought carnivorous but now known as giant herbivores, New Zealand’s giant moas that thrived until human arrival 700-800 years ago, giant ancient penguins that were top ocean predators, and pelagornithids, giant flying birds with tooth-like jaw projections that went extinct a few million years ago.