9 Extinct Animals That Once Lived Alongside Humans

From sabretooth cats to long-nosed dolphins, discover the animals that once walked beside us, from prehistory to the modern day.

Mar 24, 2023By Donna Hobson
extinct animals that once lived alongside humans

More than 99% of all Earth-based species are now extinct, thanks to steady evolution combined with five mass extinction events. However, average extinction rates have risen in the last 100 years, and we can see human activity's impact on animal habitats and populations.

We're lucky enough to share our home with the universe's most beautiful and wondrous creations: animals. But we shouldn't take their presence for granted. Here are just a handful of creatures we've already lost to extinction and the actions we can take to avoid unnecessary species loss.

Sabretooth Cat

56 million to 11,700 years ago

Smilodon fatalis  prehistoric sabre tooth cat

The Sabretooth cat, whose scientific name Smilodon Fatalis meant "deadly knife tooth," was once a fearsome predator who lived in North America and Europe before spreading into South America, Asia, and Africa.

Their appearance differed from the cats we see today; their tail was short, while a muscular build allowed them to leap on and ambush their prey. Short legs possessed huge paws with sharp claws, and their jaw could open to a 90-degree angle to make way for the 8-inch canines.

extinct animals that once lived alongside humans

Ground Sloth

35 million to 10,000 years ago

giant sloth

Sloths are one of the least threatening animals in existence, but the same cannot be said for their fearsome ancestors. The largest of the ground sloths, known as a Megatherium, could grow to the size of an elephant, measuring up to 20 feet long and weighing more than four tons. Due to the presence of long claws and sharp teeth, scientists believe that these ground-dwelling mammals may have been carnivores.

The last remaining ground sloths lived on the Caribbean islands until around 4,200 years ago, when the arrival of humans saw them ascend to the trees.

Giant Beaver

3 million to 10,000 years ago

Giant beaver

The giant beaver was the largest rodent that ever inhabited North America and was the size of a black bear. These mighty rodents were big enough to devour a human, but studies suggest they preferred a diet of primarily aquatic plants. The giant beaver lived around lakes and ponds where it coexisted with smaller members of its species. Still, they eventually went extinct, while their smaller relatives managed to survive.

This may have been because the smaller rodents found it easier to adapt to warming environments. And this small size would have made it easier for them to burrow or bite through any obstacles that blocked the way to vegetation.

Gigantopithecus

6 million to 100,000 years ago

Gigantopithecus giant ape jungle book

If you've seen the live-action remake of the Jungle Book, then you'll be familiar with the Gigantopithecus. No, it wasn't made up for dramatic effect; these 10 feet tall apes once walked the Earth. They are the largest known primate ever to exist and could weigh up to 500 kg.

After living on Earth for between six and nine million years, the last remaining Gigantopithecus died some 100,000 years ago. Changing climates meant that forests dried to savannahs, and these huge apes could no longer find enough food to sustain themselves.

Dodo

7 million years ago to 1681

dodo extinct flightless bird of mauritius

The flightless dodo was once a significant feature on the island of Mauritius, with no natural predators and a carefree existence. That was until the arrival of humans in the 16th century. Not only were they easy prey for sailors who would stock up on their meat, but the introduction of monkeys and pigs decimated the remaining population, with the last remaining bird killed in 1681.

Few descriptions of the legendary bird are available, though scientists believe they weighed around 23 kg and possessed blue-gray plumage. Researchers are discovering that the image of a dodo as a plump, clumsy bird is largely inaccurate. These birds were likely to have been much slimmer and stood taller than we often see them portrayed in images. Their body structure suggests they could have been reasonably agile on their feet and perfectly adapted to their environment.

Giant Dragonfly

300 million years ago to 250 million years ago

meganeuropsis giant dragonfly

The dragonfly is the deadliest predator in the world. Still, it's of little threat to humans thanks to its small size. But how would you feel if a dragonfly with a two-foot wingspan flew overhead? The Meganeura, one of the largest griffinfly members, would have been quite a sight to behold around 300 million years ago. Giant insects such as these could thrive thanks to increased oxygen in the atmosphere, which made breathing easier and may have increased lift by altering the air pressure.

Quagga

290,000 years ago, to 1800s

quagga photograph equine horse zebra

The quagga is one of the coolest creatures that once walked the plains of Africa. This "zebra horse" possessed black and white stripes along the front half of its body and a natural mohawk down its back. Named for its call, which sounds a little like "kwa-ha," these South African equines were once prime candidates for domestication. Sadly, excessive hunting saw their numbers drastically decline until they were wiped out entirely in the late 19th century.

Baiji

25 million years ago to 2002

baiji long nosed dolphin

The Baiji was once a long-nosed dolphin who enjoyed swimming the length of the Yangtze River in China. Sadly, the last documented sighting of these beautiful creatures was in 2002; all search-and-find missions since have proven unsuccessful. The Baiji is now classed as a recently extinct animal and is the first dolphin species to have its population decimated by humans. The cause of this sad reality are dams, shipping lanes, pollution, and overfishing.

Pyrenean Ibex

18,000 years ago, to 2,000

Pyrenean ibex european

The Pyrenean Ibex is another recently extinct mammal common across France and Spain less than 100 years ago. The exact causes of its demise remain a mystery, though scientists suggest that disease, poaching, and the inability to compete for food could have played a part.

In 2000, the last known Pyrenean Ibex (a female called Celia) was discovered dead after being killed by a falling tree. Scientists took skin cells from Celia's ear, which they used to clone the species in 2003, making it the first animal to become "unextinct." Sadly, lung defects meant the clone survived for just seven minutes, and subsequent efforts have been unsuccessful.

How Can We Prevent Further Extinctions?

panda bear animal conservation

Change is inevitable, and life on Earth is often a case of "survival of the fittest." Several mass extinction events have already occurred on Earth due to changing climates, passing comets, and environmental factors. There is no way for us to control the might of mother nature. Still, we can help to sustain the planet and engage in better everyday practices to maintain healthy habitats for the beautiful array of creatures that we are lucky enough to share our world with.

Here are some simple steps that you can take to help protect wild habitats and prevent the unnecessary loss of some of Earth's most amazing creatures:

Donna Hobson
By Donna Hobson

Donna believes that keeping a pet is the key to a happy life. Over the years, many creatures have passed through her home - Sooty the cat, Millie the rabbit, Stuart (Little) the guinea pig, and Trixie the tortoise, alongside her pet goldfish, Zippy, who lived to the grand old age of 24 years! She currently resides with her black kitten Jinx and an aquarium full of fish and snails to entrance them both. When she is not looking after her pets, Donna enjoys researching and writing the answers to all your pet-related wonders.