NATURE'S REAL-LIFE VAMPIRES

Count Dracula... Lestat de Lioncourt... Laszlo... all these vampires have got oodles of charisma, natty dress sense and an intriguing backstory. But the problem is, they're fictional. We reckon the animal kingdom can do a lot better. Suck on this...

- DR BRITTNEY G BOROWIEC

Millions of years ago, sometime during the dinosaur era, ancient arthropods experimented with an unusual new diet: blood. Those ancestors of today's mosquitoes, ticks and bedbugs were some of the first, but certainly not the last, to try haematophagy.

Though relatively rare as far as diets go, haematophagy or blood-feeding - isn't something that evolved once, or even in a small collection of closely-related animals. Haematophagy evolved independently at least 20 times in arthropods alone, as well as in a bunch of worms, some fish, and a few birds and mammals. Despite all this diversity in animal form, each coven of vampires had to tackle similar problems to refine their grisly lifestyle.

THE RED STUFF

A diet as specialised as blood, a renewable but not easily accessible resource, doesn't appear out of nowhere. Mouthparts originally used for piercing or cutting other food, like plants, gave prototype blood-feeders a head start. Many were also fortunate to live in the right place, on and around potential hosts, as scavengers, parasites, or even predators. Supported by these 'pre-adaptations', it was perhaps only a matter of time before some creature struck blood, discovering deep wells of untapped sustenance flowing just beneath the skin, like a Cretaceous-era oil prospector.

But unlike oil, which is the essence of squished and melted carcasses, blood is alive. It's always moving, shuttling essential nutrients, oxygen, and everything else around the body. It's full of electrolytes and protein, making it a better diet than the plant juices and waste that 'pre-blood-feeders' would have sustained themselves on.