Following last week’s discovery of the remains of a giant bird, we look at some of the most formidable beasts on record

Pachystruthio dmanisensis

Last week, researchers published a paper about the remains of a giant flightless bird found in a Crimean cave. Pachystruthio dmanisensis is believed to be from a family of prehistoric birds with powerful legs and large beaks, present across North America, Asia and Europe. The gigantic creature could grow to 3.5 metres in height and weigh about 450kg. By contrast, the ostrich is the largest living flightless bird and can reach 2.7 metres and weigh 150kg. The exact reason for Pachystruthio’s extinction is unknown, though it may have been due to some of the deadliest predators of the last ice age.

Glyptodon

Facebook Twitter Pinterest Glyptotherium arizonae, a North American relative of the armadillo. Photograph: Alamy

Glyptodon was a genus of a supersize, distant relative of today’s armadillos. They lived in North and South America between 5.3m and 12,000 years ago and were encased from head to tail in a thick protective shell. Evidence suggests they were driven to extinction by a combination of climate change and hunting, as humans used their shells for shelters.

Short-faced bear

Facebook Twitter Pinterest A short-faced bear could run at speeds of up to 40mph. Photograph: Stocktrek Images/Alamy

This enormous bear lived in North America between 2m and 11,000 years ago. Despite its name, it did not have a particularly short face – it just seems small in comparison to its giant limbs. Its long legs enabled it to run at speeds of up to 40mph to hunt down its prey, which included wild horses. The bear would have been roughly 3.3 metres tall on its hind legs and weighed between 700 and 800kg. Competition from other species, including humans, is thought to have played a part in its disappearance.

Mammoth

Facebook Twitter Pinterest Lyuba, a 42,000-year-old baby mammoth, at the Museum of the World Ocean, Kaliningrad, Russia. Photograph: ITAR-TASS News Agency/Alamy

Remains of mammoths have been found on all continents except Australia and South America. The woolly mammoth is the best-known of the species, and evidence suggests that small populations survived in North America until approximately 10,500 to 7,600 years ago. They could grow up to 4 metres in height and weigh 6,000kg. Extensive hunting by humans and a lack of genetic diversity pushed this relative of the elephant to extinction.

Megalodon

Facebook Twitter Pinterest The Megalodon shark grew to three times the length of today’s great white shark. Photograph: Corey Ford/Alamy

Thought to be the largest shark that ever lived, its remains have been found on every continent except Antarctica. Megalodon lived between 23m and 2.6m years ago. It grew up to 18 metres in length (the largest recorded great white shark is 6.1 metres). It was originally thought Megalodon died out because of falling sea temperatures linked to climate change. However, research conducted in 2016 has led scientists to conclude that the evolution of the food chain and increased competition may have been the primary factors in its extinction.