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It's the series that will open your eyes to the wonders of the animal world. Yesterday, nature writer SIMON BARNES revealed the astonishing lives of birds. Today, he tells why you should learn to love vampire bats - and rats...

The world would be a much happier place if humans were more like vampire bats. It's their unselfishness I'm talking about: the free giving of something you need but are prepared to surrender to another.

We humans like to think that altruism in any form is uniquely human: a real and above all moral division between us and the rest of the animal kingdom. Vampire bats contradict this view.

All kinds of legends have built up around this pint-sized creature of the night, but one bit at least is true: that they do actually drink blood. There are three species: the white-winged vampire and the hairy-legged vampire prefer the blood of birds, and are adept at clambering through the branches to reach nests and nestlings.

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Bad rep: Vampire bats are social and help each other out in times of need - albeit by regurgitating blood

Common vampires prefer to feast on mammals, mostly livestock, but they will on occasions drink human blood. It's said that the bite is not painful, although — or perhaps because — they use razor-sharp incisors to remove the skin; the resulting wound has been described as looking like a golfer's divot.

Vampires are around 4in long, with a wingspan of 7in or so. They are adept on the ground, crawling with agile speed to reach a target and search out a convenient blood vessel.

The anti-coagulant in their saliva allows the blood to flow, and they lap it up like a cat with a saucer of milk; on a good night they can take a meal of half their own body weight.

This sounds as if all the odds favour the bats, but this is not so. It's common for a vampire bat to go through a night without a meal; within three days it will have starved to death. Blood-hunting is a skill that improves over time: year-old bats will fail one night in three; experienced animals fail only one night in ten.

All the same, failure is a fact of life for even the best blood-hunters.

Dinner: Anti-coagulant in their saliva allows the blood to flow, and they lap it up like a cat with a saucer of milk

Vampire Bats love a tasty baby penguin

Vampires are social creatures, coming back to the same day-roost at the end of every night. There are some big colonies, up to 2,000, but most are much smaller, and centre on a core population of females who, even if not related, tend to know each other well.

A bat who has failed to find blood in a night's flying will beg a meal from a neighbour. From a friend, we would say, if we weren't so terrified of sounding anthropomorphic.

The friend will then regurgitate blood, thus sharing a meal. Under this system, females have been known to live for up to 15 years.

Reciprocal altruism is still altruism; obviously this is a system that works on a mutual back-scratching basis.

Human society depends on the small kindnesses that you perform as a matter of course and that you expect to be performed for you in turn. But it is not just humans who are humane.

Seagulls that haunt landfill sites, pigeons that fly around city centres, cockroaches in our kitchens: all these we treat with contempt. But when it comes to fear and loathing in the animal kingdom, nothing beats a rat.

The brown rat is one of the great success stories of the last millennium. Not known in Britain before the 11th century, it has become a seldom-seen omnipresent fact of town and country life.

Rubbish reputation: But the brown rat is one of the greatest success stories in nature in 1,000 years

We are never more than 10ft from a rat in a city, so they say: information designed to make our flesh creep. There are more rats than people in Britain; in New York alone there are said to be 100 million of them.

I live in the countryside and keep horses and chickens — so naturally, I have rats. They pollute my animals' feed and they damage stuff, so I try to control them, which is a euphemism for killing them.

But why, actually, is there a need for wild species to be under human control? The idea of losing control, of being unable to regulate the numbers of wild animals we have around us, is something that profoundly distresses us modern humans.

It is an insult to our omnipotence, a serious challenge to our understanding of ourselves and our place on the planet. Humans define ourselves by our control — and yet there is a contradiction within 10ft of you.

We may be able to eradicate a lot of species with great efficiency, both on purpose and by accident, but there are some species that we simply can't control, no matter how hard we try. They are just too good for us: too smart, too well adapted, too effective.

Hardy: We may be able to eradicate a lot of species with great efficiency, but there are some we simply can't

Western civilisation has never had many good things to say about rats, for all that they have been roped into thousands of scientific experiments for the very good reason that rats can tell us an awful lot about human beings.

But some cultures are less single-minded in their detestation of rats. I have visited a Jain temple in southern India in which the rats were not only fed but honoured. In some Indian cultures, rat meat is considered a delicacy.

In the Chinese horoscope, the year of the rat is by no means inauspicious; its natives are said to be creative, intelligent, generous, honest and ambitious.

There is a fine statue commemorating a rat with such qualities in Kyoto, Japan; you can find it if you do the Philosopher's Walk, a stroll that takes you past a number of Zen temples. It's a walk devised for contemplation of higher things.

What's to hate about rats anyway? Sure, they're ubiquitous, destructive and far too effective at breeding. But as you stroll on the Philosopher's Walk, you are entitled to ask yourself: well, who isn't?

Not far behind the rat in the fear and loathing department comes the hyena.

These are the cheats of the animal world, scavenging the leftovers of the noble lions, stealing the kill from the leopards and giving everyone the willies when they are caught in the safari vehicle's headlights with their grinning Halloween-mask faces.

Laughing: They are cheats and scavengers - but hyenas have big brains and a better social life than lions

The bare skin of the face gives them a particularly malevolent appearance; it doesn't help when you explain that this is an adaptation that helps them to keep clean, a useful thing for a beast that spends so much of its time with its head stuck in corpses.

The spotted hyena is the one we are most familiar with, from wildlife documentaries if not from experience on safari. Their glorious whooping calls — they like to keep in contact with each other — are one of the great sounds of the African night: a spine-tingler for the first-timer, and providing a sense of homecoming for those of us who keep going back.

Hyenas always have an air of being up to no good, of being caught in the middle of some episode that even they must admit is rather shaming, but they're going to do it anyway, so off they go into the bush, grinning hard.

Yet there is a lot to recommend a hyena. Their social life is rigidly efficient, and they have big and complex brains, which make this possible. They live by the clan, and everything they do is tied up with the female dominant hierarchy that underpins it.

This contrasts with the social life of lions, which always seems to operate in a haphazard and rough-and-ready way. Lions seem to be making it up as they go along, and are perfectly capable of breaking all their own rules.

There is beauty to be found in the hyena. Its sense of smell is more than 1,000 times more acute than ours

Round a kill, the male does what he wants and everybody else scraps for the next bite, rather than waiting for a preordained turn, though the alpha male lion will tolerate a cub — but no one else — eating alongside him.

Lions are highly social but not really on top of their own social lives, in a manner that reminds me of modern humans.

But hyenas have it all worked out. The boss female is in charge. It has been estimated that the top female is two-and-a-half times more likely to raise successful young than any of her peers.

A hyena den is, against all expectations, a lovely sight: always busy and playful. The pups, all black, look as if they would be perfectly at home on your hearthrug.

There is great beauty to be found in the hyena. Its sense of smell is more than 1,000 times more acute than our own. Their powerfully muscled jaws and bone-crushing premolars give them one of the most effective bites in the world.

As so often, the truth and beauty of the creatures we live with are obscured by human traditions and untrue assumptions. We are not encouraged to look closely or think afresh about non-human animals because, after all, we know everything. Or do we?

Extracted from Ten Million Aliens: A Journey Through The Entire Animal Kingdom by Simon Barnes, published by Short Books at £20. © 2014 Simon Barnes. Offer price £16 until October 25, 2014. Order at mailbookshop.co.uk or call 0808 272 0808, p&p free for a limited time only.