9 extinct animals you should know about

Some scientists hope to bring the woolly mammoth back from extinction, but with African and Asian elephant populations still facing a huge range of threats, many believe that our focus should be on preserving those animals instead.

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Dodo (Raphus cucullatus)

For a large bird species that only became extinct relatively recently, we know surprisingly little about the dodo and its behaviours. In fact, there is just one near- complete dodo skeleton with bones from one bird, and there is only one specimen that contains soft tissue.

What we do know is that the dodo was restricted to Mauritius, an island in the Indian Ocean off the eastern coast of Madagascar and part of the Mascarene Archipelago, and was a relative to doves and pigeons. It’s thought that natural selection caused the animal to evolve into a flightless bird, with the species no longer needing to fly on an island with no predators.

However, when humans – and the animals they brought with them – first came to Mauritius in the 16th century, the dodo became extremely vulnerable. As well as being hunted for meat, it suffered from habitat loss and the predation of its eggs, resulting in its extinction by c1680.

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Thylacine (Thylacinus cynocephalus)

Also known as the Tasmanian tiger or Tasmanian wolf, the thylacine was a carnivorous mammal originally found in Australia and New Guinea. Despite being similar in appearance to the domestic dog, it was actually a marsupial – a group of mammals that also includes kangaroos, koalas, wombats and opossums – and had a pouch.

Once widespread, the thylacine became extinct on the Australian mainland no less than 2,000 years ago, although the reasons for this are unknown. The species then became restricted to the island of Tasmania, off the south coast of Victoria, with between 2,000–4,000 individuals remaining when the British arrived in the early 19th century.

Eventually, the thylacine was persecuted as it was deemed a threat to livestock. The last known captive individual died from exposure at a zoo in Hobart in 1936 after being accidentally left out overnight. It’s thought that the last wild thylacines died in the 1960s, but that hasn’t stopped persistent rumours over the species’ continued survival.

Great auk (Pinguinus impennis)

Despite being similar in colouration and shape and bearing the genus name Pinguinus, the great auk wasn’t a relative of penguins, but was instead a member of the same family as puffins and guillemots.

Once a relatively common species in the North Atlantic, it bred on remote rocky islands such as Funk Island off the coast of Newfoundland, which was described by one 18th- century sailor as being “entirely covered with those fowls, so close that a man could not put his foot between them.”

However, exploration of the North Atlantic seas by European sailors spelled danger for the flightless seabird, with overharvesting of its eggs and adults for meat, feathers and body parts dramatically reducing the population. Attempts were made to protect the great auk, but that only increased its worth to collectors.

Sadly, the last breeding pair were killed and their single egg accidentally crushed by fishermen on Eldey Island, Iceland, on 3 July 1844.

Xerces butterfly (Glaucopsyche xerces)

Named after the Persian kings Xerxes I and Xerxes II (whose names are sometimes spelled ‘Xerces’ in France), this diminutive blue butterfly species lived among the coastal sand dunes of the San Francisco Peninsula, where its caterpillar preferred to feed on a single plant species.

However, urban development resulted in the loss of the plant, which could not survive in disturbed soil, and thus the loss of the Xerces blue in the 1940s – the first example of a butterfly becoming extinct due to human activity in North America.

Later, the Xerces Society, a non-profit conservation organisation established in 1971, was named in memory of the lost invertebrate.

For a while, there was uncertainty as to whether the Xerces blue was a distinct species or a subspecies of another blue butterfly. However, a scientific paper published in 2021 examined the DNA of a museum specimen collected in 1928 and proved that it was indeed a distinct species.

Passenger pigeon (Ectopistes migratorius)

The passenger pigeon was one of the most abundant pigeon species on the planet. Native to North America, it was called jahgowa by the Seneca Tribe, which translates to “big bread”, as it was a source of food by the Seneca and the rest of the Haudenosaunee people. Despite this, the hunting of the species was carefully regulated by rules set by each tribe.

However, after colonisation by the Europeans, hunting of the passenger pigeon increased and gradually became more industrial and commercialised. As the population declined, the species then became vulnerable to further pressures such as habitat loss and predation by other animals.

The last living passenger pigeon was a female named Martha, who was kept at Cincinnati Zoo in Ohio. She died on 1 September 1914 – one of the few times we have known the absolute date of a species’ extinction. Her death contributed to the creation of the US Migratory Bird Treaty Act, which requires permits to hunt some migratory bird species.

Golden toad (Incilius periglenes)

So-named for the brilliant yellow-orange colouration of the male (the female was black with yellow and red patterning), the golden toad has become a poster child for extinctions connected to the climate crisis.

Found in the Monteverde Cloud Forest of Costa Rica, the amphibian spent most of the year underground. It only emerged for a few days each April, with males fighting with each other around pools of rainwater in order to mate with females.

In 1987, roughly 1,500 golden toads were observed. However, the following year, only 10 toads were found, and in 1989, just one male. That one male was the last golden
toad ever seen, and the species was officially declared extinct in 2004.

While the exact cause of extinction is unknown, the climate crisis – combined with habitat loss and an infectious disease called chytridiomycosis – are all thought to have played a part.

Baiji (Lipotes vexillifer)

The baiji was a freshwater dolphin that lived in the Yangtze River in China, the third-longest river in the world. Although still listed as ‘Critically Endangered’ on the International Union for the Conservation of Nature’s Red List, having last been assessed in 2017, the species is considered extinct by conservationists. In fact, both the last confirmed sighting of a wild individual and the death of the last captive individual occurred in 2002.

The Yangtze River is also home to the Yangtze finless porpoise, the only freshwater porpoise in the world. Like the baiji, its existence is currently threatened by overfishing, shipping traffic and noise pollution.

However, the 2017 suspension of sand mining in Dongting Lake – a flood basin of the Yangtze in China’s Hunan province – has seen the finless porpoise return to areas that it had previously been avoiding.

Pinta Island giant tortoise (Chelonoidis nigra abingdonii or Chelonoidis abingdonii)

While there is debate about whether the giant tortoises of the Galápagos Islands are subspecies of the same species or a completely different species altogether, one thing is certain: Lonesome George was the last of his kind.

George was a Pinta Island tortoise, a species (or subspecies) that was already thought to have been extinct until he was discovered alone on the island that gave George and his former companions their collective name.

There were attempts to find other Pinta Island tortoises, and to mate him with closely related females, but to no avail. He died in 2012 of natural causes when he was around 100 years old.

Curiously, scientists believe it might be possible to bring back the Pinta Island tortoise, or at least a closely related version. Researchers have discovered hybrid tortoises with Pinta Island tortoise genes on nearby Isabela Island, with their Pinta Island ancestors having been moved there by whalers and pirates.

Megan Shersby is a naturalist, science writer and communicator. She was previously editorial and digital coordinator at BBC Wildlife Magazine

This content first appeared in the November 2023 issue of BBC History Revealed