The Royal Society of London has compiled a list of the world’s most “evolutionarily distinct and globally endangered” (EDGE) mammal species and features the top 100 on a fantastic website.

These animals are so unique, in terms of their anatomy or behaviour, that if they were to go extinct there would be nothing else on earth like them. And almost certainly never anything like them ever again.

Here are some of my favourites from the list, many of which I think you might not have heard of. (Oh, and of course I didn’t take these photos myself – I don’t make a habit out of photographing blue whales – but if you click on the photo it will link you to the original website where the photo was posted… so please don’t email me and shoo me away from linking to your site, this is all in the interest of conservation, ok? Ok.)

Aye aye (number 16)

It’s kind of like a woodpecker lemur. It uses its spidery fingernails to pick grubs out of trees. The species is mainly threatened by deforestation (like just about everything else in Madagascar). The fact that local people consider it an evil omen and kill them on site doesn’t help either.

Pygmy hippopotamus (21)

There are not many left in the wild, today they nearly all live in zoos. Apparently almost all the hippos living in American zoos are descended from one hippo, “Billy,” who was given to President Calvin Coolidge as a gift. Coolidge was also the proud owner of twelve dogs, six birds, three canaries, two racoons, a donkey, a bobcat, a bear, an antelope, a wallaby, and a lion. (James Buchanan had an elephant though, which I think trumps Coolidge.)

Slender Loris (22)

Sadly, these sticky little primates are actually hunted for food in Sri Lanka. People also apparently use their tears in traditional medicine – I shudder to think how they obtain them.

Southern marsupial mole (31)

Not actually a mole – but it looks and behaves almost exactly like Africa’s golden mole. Like many other animals that grow up on islands, it evolved to occupy the ecological space (niche) for a species that was missing on the island. In this case moles, which are absent from Australia. This little guy (eating a gecko in this photo, to give you an idea of its size) literally swims through the desert sands, just like golden moles. If you can get yourself a copy of the BBC’s Life of Mammals (and I recommend that you do) one of the episodes has footage of a golden mole hunting grasshoppers – both fascinating and hilarious.

Fossa (43)

Scientists only fairly recently figured out that this animal is a civet, and neither a cat nor a dog. The animals can copulate for more than two ours, owing to the unhappy fact (for the female at least) that the males have sharp barbs on their pensises. They use these to keep the females stuck to them long after they have ejaculated in order to give their seed time to implant before she tries to mate with anyone else. Classy.

Golden rumped elephant shrew (46)

It looks like a shrew with an elephant’s trunk and a glowing golden bum. What more could you want? And to make it even cooler, it’s not actually a shrew – it is a very unique and ancient animal that is more closely related to aardvarks, manatees, and in fact, elephants.

Bumblebee bat (49)

The world’s smallest mammal. What more need be said? Only found in 21 caves in one small part of Thailand. Apparently one contributing factor in the decline of this species was frequent visits to their caves from nosy tourists wanting to see the world’s smallest mammal. The constant disturbance to their sleep sapped them of their strength and caused many to die, according to the Thai website this photo came from.

Blue whale (88)

The largest animal that has ever lived (as far as we know – although I’m willing to bet there may have been some killer monster sea reptiles, bigger than mosasaurus, that we just haven’t found yet).

Maned three-toed sloth (63)

I had a prof at uni who studied sloths. When he told the class this, we all burst out in laughter (can you think of a more boring-sounding animal?). He smiled and said “Ah, they’re fascinating animals – they have an extra cervical vertebrae!” (Most mammals have seven vertebrae in their necks, sloths have 8 or 9, which allows them to turn their heads much more freely.) We laughed some more. But you know what? He’s right. They are incredibly neat. They are nonetheless astonishingly slow – this subspecies must seem like a part of the scenery even to the animals that live around it. Its mane is home to beetles, moths, and algae.

Philippine flying lemur (71)

The evolutionary origins seems difficult to resolve – it being so strange and all – but it seems to be an ancient kind of primate. Which would make it the only “flying” primate in the world – except of course for the Wicked Witch of the West’s flying monkeys. It has a larger wingspan than any other gliding mammal, including all the flying squirrels.

Long-eared jerboa (81)

I mean, come ON! Look at those EARS!

Old world sucker-footed bat (94)

Not to be confused with the new-world sucker footed bat. The two species evolved sucker feet completely independently of each other. We don’t have any idea of how many there are of these in the wild in Madagascar, there have been only a few sightings of the animal ever – one of the first occured when somebody found one inside a coiled leaf they were holding in their hand.

And last – but most certainly not least – the number one ranked EDGE species on their list:

Baiji (1)

Sadly, the Chinese river dolphin should probably be scratched off the list – an attempt to estimate the number of animals left last year turned up not a single one. Which isn’t surprising – it uses echolocation to hunt, and in the noisy (and polluted) waters of the Yangtze, they simply couldn’t catch enough fish (or probably even find each other to mate). It would be like living your entire life in a filthy brown fog that prevented you from being able to see more than a foot in front of your face (or, as my aunt calls it, living in Los Angeles).

Let’s take a moment of silence please for the baiji. If f-ing Anna Nicole Smith gets an entire f-ing day of coverage on CNN, the least we can do is take one minute for this infinitely more interesting and intelligent creature.

There are still three other species of river dolphin – the Ganges(65), Indus (66) and Amazon (140) river dolphins. None of these animals are actually dolphins – they are in fact very ancient species of whales that evolved when the Amazon basin and parts of central Asia were covered in shallow seas. As the water receded and turned into rivers, these whales stayed, and today are the only freshwater cetaceans in the world. What’s more, the Indian, Amazonian and Chinese varities are unrelated – they just evolved to look very similar because they lived in such similar habitats. They do each have some distinctive and cool features: the Indian river dolphins lacks eye lenses (I believe they are the only mammals like this), and swim along their sides. The Amazonian river dolphins are often pink – like, seriously pink:

It’s too late for the baiji, but it’s not too late for the other three. The Amazonian species is doing ok (at least a few ten thousand left), the Indian ones very badly (around 1200 of each subspecies remain). We can learn from what happened to the baiji, by ensuring that the Ganges, Indus and Amazon don’t end up as filthy and noisy.

Hopefully the baiji’s demise will serve as a lesson – and not simply a prelude to the extinction of these other three fantastic animals.