A look at the animals whose disappearance could leave a mark on us all.

1/7 Elephants Elephons are among nature’s stranglers.

The creatures are often thought of as the most powerful of all land animals, but this isn’t always the case.

The elephant’s trunk and its limbs can crush rocks, but it can also be very agile.

In fact, some experts think elephants are the only land animals capable of surviving without help from humans.

“Elephants are extremely fast and powerful, but their speed is very limited, they cannot reach distances that humans can reach,” said Paul Rutter, a lecturer in animal behaviour at the University of Exeter.

“Their muscles and tendons are quite weak.”

2/7 Flying squirrels Squirrels are one of the world’s most bizarre animals, with their strange flapping wings, tiny legs and tails.

While it might seem a little strange to see one of these things in flight, the fact is that squirrels have long been known to climb trees and even fly in the air.

“It’s actually very common for squirrels to hang upside down or hang upside-down from branches and logs,” explained Rutter.

“But in most of the rest of the animal kingdom, they are much more agile than most birds.”

3/7 Black widow spiders Black widows are one the most venomous spiders in the world, and one of nature’s most mysterious creatures.

Named after the female black widow spider, they look more like miniature caterpillars than anything else.

Black widowed spiders have long existed in many parts of the globe, but the last recorded sighting in Australia was in 1879.

In Australia, the black widow was thought to have been introduced to the continent in the 1600s.

“Black widows have been reported from New South Wales to Western Australia and Tasmania to Tasmania, and it’s been estimated that there could be as many as a million of them in the country at any one time,” said Rutter in a news release.

“There are about 30 species in the United States, and the only species that has been found in Australia is the black widows, which live in the southern part of the continent, about 400 kilometres (250 miles) east of Darwin.”

4/7 Giant squid The world is filled with huge, beautiful creatures, but few would ever think of calling a giant squid an animal.

Yet the giant squid is one of life’s great mystery creatures.

The squid, which can grow up to 10 metres (33ft) in length, is one the largest animals in the ocean.

“Giant squid is a member of the family Scleractinae, which includes squid, octopi and squid mussels, and has been described as having a head that is approximately the size of a melon,” explained Dr Andrew Smith, a marine biologist at the Australian National University.

“Its tentacles are used for feeding and secreting food and other organisms, and also have a very strong bite.”

5/7 Tiger shark This is a rare sighting of a tiger shark off the coast of Western Australia, but what’s more unusual than this rare sighting is the fact that the tiger shark is actually quite common off Australia.

Tiger sharks are often mistaken for great white sharks because of their distinctive colouration, but they are actually much more closely related to the bluefin tuna.

They are found off the Queensland coast and off the northern tip of the Western Australian coast, but are much larger than the great white.

“They are quite rare, but I have seen one tiger shark in the wild, off the Western Cape in 2016,” said Smith.

“I have no idea why they are so common, and I have no way of knowing whether it’s because they’re really large or because they’ve been taken by fishermen.”

6/7 Manta rays Manta ray is the largest ray in the animal world, with a wingspan of around 1.5 metres.

It’s the only ray in which its dorsal fin protrudes and is actually a membrane that keeps the rest a little closer to the body.

The dorsal fin is covered with a layer of fat called a supraglottic layer, which is what keeps the rays body temperature relatively high.

Manta’s dorsal fin can grow as long as 3.5cm, which means the rays entire body can be covered in a single layer of fatty tissue.

Manna rays can live up to 50 years.

7/7 Polar bear The polar bear is one one of our closest living relatives, and is one a lot of people would like to see return to the wild.

“The polar bear has been a subject of considerable controversy over the years because of its widespread illegal trade and its potentially devastating impacts on polar bears,” said Andrew Smith.

Polar bears are found in the Arctic and Antarctic, and have been documented in captivity for more than 200 years.

Polar bear numbers have declined over the past decades