10 Extinct Mammals (With Photos)

Written by Volia Nikaci
Updated: November 9, 2022
Image Credit Daniel Eskridge/Shutterstock.com
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Key Points:

  • The last known Quagga, an extinct mammal subspecies of zebra, died in The London Zoo in the late 1800s.
  • The Saber Toothed Tiger was actually related to marsupials and had teeth that grew to 7 inches in length and jaws that could open to over 90 degrees.
  • The gigantic Irish Elk were actually not elk – but the largest species of deer ever known. Their antlers spanned 12 feet across and weighed over 90 pounds!

We can study animals from all over the world thanks to science, but what about those that no longer exist? The list of extinct mammals could go on for ages, but each animal has a unique story. With today’s advanced research, we can learn so much from animals that haven’t even existed during our lifetimes!

Scientists who identify, analyze, and classify fossils are called paleontologists. These researchers use both the prehistoric data found in fossils and comparisons to related species that remain to draw conclusions about these extinct creatures. Carefully examined fossil evidence can help paleontologists understand more about an extinct animal’s social order, diet, behavior patterns, and more.

Join us as we go through 10 extinct mammals that will leave you utterly amazed.

1. Thylacosmilus

Saber-toothed tiger
The saber tooth tiger had a thick coat with a yellowish-beige color.

Daniel Eskridge/Shutterstock.com

Often referred to as the “saber-toothed tiger,” this mammal is closely related to marsupials. This incredible extinct predatory animal can be most recognized by its two long, razor-sharp canine teeth. These teeth could grow longer than 7 inches and were carefully crafted to cut through tissue, allowing them to inflict the greatest damage on their prey. Not only did they have outstandingly long teeth, but an amazing jaw that could open over 90 degrees. The thylacosmilus was one magnificent animal that, unfortunately, was classified as an extinct mammal.

2. Eobasileus

Eobasileus
In its habitat, Eobasileus was one of the largest animals with an upper size similar to that of a large black rhinoceros.

Charles R. Knight (1874–1953) / public domain – License

Although it looked like a rhinoceros, the Eobasileus was a mammal species belonging to the order Dinocerata. This incredibly large beast was 13 feet long and weighed over 8,000 pounds. This creature had 3 pairs of horns atop its skull, similar to that of a giraffe. Eobasileus had an incredible pair of strong large tusks on its jaw and lived 45 million years ago.

3. Quagga

A sketch of the extinct Quagga.
South Africa’s quagga (Equis quagga) became extinct at the end of the 19th century.

miha de/Shutterstock.com

Quagga is an extinct mammal subspecies of zebra that were incredibly unique in its own way. The quagga was said to look like a mixture of a zebra and a horse. This is because the rear part of its body was all brown, and the front contained a variety of stripes. Each quagga had its own set of individual stripes. The last living quagga resided in the London Zoo throughout the late 1800s.

Additionally, this quagga was the only one ever to be photographed. The quagga had incredibly long legs made for endurance and speed, which allowed them to reach over 40 mph. They would also use these incredibly strong legs for defense and give an extremely hard kick if provoked.

4. Thylacine

tasmanian tiger 3
In modern times, Tasmanian Tigers were the largest carnivorous marsupials.

Adwo/Shutterstock.com

The Thylacine, also known as the Tasmanian Tiger, wasn’t much of a tiger at all. This marsupial mammal was said to resemble more of a medium-sized dog than it did a tiger. These incredible animals weighed anywhere from 30 to 60 pounds and had striking yellowy brown fur. Thylacines were timid animals that communicated mainly through yaps and barks like dogs. Sadly their extinction was caused at the hands of humans through excessive hunting of the animal. The last Thylacine of its species sadly passed away in 1936 at the Beaumaris Zoo, where it was held in captivity. 

5. Irish elk

Largest Deer Ever - Irish Elk
The Irish elk was one of the largest and heaviest deer ever to walk the earth.

Daniel Eskridge/Shutterstock.com

A funny fact is that the Irish elk was not actually an elk but the largest deer species ever known. These gigantic mammals were 7 feet tall and had massive antlers atop their head that spanned 12 feet. Just the antlers on their own weighed 90 pounds! These incredible beasts were said to have been roaming the earth about 8,000 years ago before becoming extinct. Although scientists don’t know exactly why the Irish elk went extinct, there are a few theories. Some believe its size alone was the reason that contributed to its extinction, while other theories suggest a food shortage might have caused them not to be able to fulfill their dietary needs.

6. Pyrenean Ibex

Largest extinction events on earth
For a brief period in 2003, the Pyrenean Ibex was declared ‘unextinct.’

Alexandre Boudet/Shutterstock.com

The Pyrenean Ibex was a species of goat that became extinct in the 2,000s. These extinct mammals could be found living throughout the Pyrenees Mountains along Spain and France and mountains throughout Asia and Africa. They chose to live on cliffs to protect themselves from predators. Scientists aren’t entirely sure what caused the Pyrenean Ibex to become extinct, but many believe it could’ve been due to hunting and diseases. Interestingly, scientists tried to clone the Pyrenean Ibex back into existence, but sadly the baby died due to health problems shortly after birth.

7. Steller’s Sea Cow

Steller's Sea Cow
A Steller’s sea cow was one of the largest mammals in the ocean at the time, and they resembled manatees.

Liliya Butenko/Shutterstock.com

Steller’s Sea Cows were larger than manatees, one of the largest members of the sea cow family. These incredible aquatic animals could grow to up to lengths of 25 feet and weigh over 8,000 pounds. They were called sea cows because they lived in herds and fed on seagrass near the water’s surface. Sadly this amazing creature became classified as an extinct mammal due to rapid hunting by humans. Sailors and fur traders would hunt them for their fat and meat, and since these sea cows weren’t fast swimmers, this made them an easy target.

8. Bali Tiger

Bali tigers are an extinct subspecies of tigers that once inhabited the Indonesian island.

Hary Atwell / Creative Commons – License

The Bali Tiger is a big cat species that lived on the Indonesian island of Bali before its extinction. This incredible tiger was around 7 feet long and weighed over 200 pounds. Various prey was consumed by these carnivorous mammals, including monkeys and wild boars. They had a beautiful orange fur coat with an array of dark and white stripes throughout their body. The Bali Tiger became extinct in the 1950s due to hunting and destroying their habitats, making it much harder for them to find prey.

9. Woolly Mammoth

2 woolly mammoths fighting in a snowy landscape
When King Tut ruled ancient Egypt, there were living mammoths on the planet.

Dotted Yeti/Shutterstock.com

One of the most well-known extinct animals is the woolly mammoth. Woolly mammoths are close relatives of modern elephants and were incredible creatures. Unlike elephants today, woolly mammoths had thick brown fur that covered their entire bodies, and this was due to the extremely cold temperatures they lived in. Woolly mammoths became extinct over 10,000 years ago due to climate change, but there are theories to suggest humans may also have been a part of the reason.

10. Camelops

Camelops hesternus
In terms of height, camelops stood about 7 feet (2.2 meters) tall.

WolfmanSF / CC BY-SA 3.0 – License

A camelop is an extinct mammal of the subfamily of camels that roamed North America over 11,000 years ago. These incredibly large animals reached heights of 7 feet and weighed almost 2,000 pounds. According to some scientists, camelops are more closely related to llamas than to camels. As they roamed, they grazed on plants and shrubs. Climate change and the arrival of humans and hunting are believed to be why the camelops are now extinct.

Up Next…

This is just the beginning of all the knowledge that the work of paleontologists can offer us. Continue exploring animals of the past with these fact-filled features.

  • 10 Dinosaurs With Horns – Learn about the curved crest of the machairoceratops, the extra-large horns of the achelousaurus, and other horned dinosaurs in this fascinating list.
  • What was the Largest Prehistoric Hippo? – Did you know that the prehistoric Hippopotamus gorgops were more than twice as heavy as modern hippos? Click here to find out what else made them unique.
  • 10 Incredible Woolly Mammoth Facts – Take a deeper dive into what scientists have discovered about these prehistoric mammals, including where and when they shared the planet with humans.

Largest Deer Ever - Irish Elk
The Irish elk had massive antlers and is believed to have weighed more than 2,000 lbs
Daniel Eskridge/Shutterstock.com
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About the Author

Volia Nikaci is a freelance copywriter and content editor with a passion and expertise in content creation, branding, and marketing. She has a background in Broadcast Journalism & Political Science from CUNY Brooklyn College. When she's not writing she loves traveling, perusing used book stores, and hanging out with her other half.

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