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Vampire Bats and Vampire Plants

The Rise of the Vampires

Bats are an old mammal species. However, since their small, delicate skeletons do not fossilize very well, there is more we don’t know about the evolution of bats than we do know. We do know that they are a mammal species that evolved around 60 million years ago, already in the form they are today, and even before the first dogs, cats, and horses.

Most bats today are tiny, some only as long as your thumb. But others, like the golden-crowned flying fox (Philippines), have a wingspan of six feet. They started out as herbivores, and somewhere along the line, some bats included insects into their diet. But then another species emerged, and just 4 million years ago, about the time the first hominids were standing upright, the vampire bats had evolved all necessary adaptations for blood-feeding, a dietary trait called hematophagy, making it one of the fastest examples of natural selection among mammals.

The vampires also evolved physical changes — vampire bats have short, conical muzzles. They also lack a nose leaf, instead having naked pads with U-shaped grooves at the tip. Some vampires have specialized thermoreceptors on their nose, which aid the animal in locating areas where the blood flows close to the skin of its prey. In addition, a nucleus has been found in the brain of vampire bats that has a similar position and histology to the receptors of infrared-sensing snakes — it means they can almost “see” where the warm blood is flowing.

A vampire bat has front teeth that are needle sharp and also specialized for cutting; plus, the part of the bat’s brain that processes sound is adapted to detect the regular breathing sounds of sleeping animals — even in pitch darkness, they can find you.

Lastly, while other bats have almost lost the ability to maneuver on land, vampire bats can walk, jump, and even run by using a unique, bounding gait, in which the forelimbs used as the wings are much more powerful than the legs.

We are lucky that vampire bats are small. Because if they had ever evolved to be larger and more formidable, they would have been a terrifying and deadly creature of the night, and something more akin to their legend.

The Dodder vine: The vampire of the plant world.

A parasitic vine nicknamed the “vampire plant” sounds frightening enough, but new studies have found that the dodder vine is even more cunning and creepy than anyone imagined.

No, the dodder hasn’t evolved to drink blood (yet), but it earned its ominous nickname for the way it does suck nutrients from its host. The vine wraps itself tightly around a host plant, and where the vine touches the host, it produces structures called haustoria. These invade the “skin” of the host and begin to feed from its vascular system — hence, the vampire analogy.

Scientists have known for years about the vine’s ability to steal water, sugar, and minor molecules from host plants. However, at the point of contact between the parasitic vine and the host, the dodder is injecting back its messenger RNA into the host. This could be really sinister because these information blocks could be telling the host what to do, and in fact, the parasitic plant is actually controlling the host. It would be in the vampire dodder’s interest for the host to be creating more of the nutrients that the parasitic vine seeks, and also for the host to lower the guard of its defenses.

In an eerie time-lapse video, the dodder tendrils waved in the air, seeming to be searching for a victim to attack. And they certainly were, because the dodder can detect chemical signals given off by a suitable host, and once detecting one, they grow straight toward it. Then they latch on, embrace their victim, and begin to drink!