Social relationships help vampire bats facilitate unusual blood diets

You can probably picture a vampire: pale, sharp-toothed, undead bloodsucker, deterred only by sunlight, religious paraphernalia, and garlic. They are gnarly creatures and are often a favorite subject of movies or books. Luckily, these are just imaginary… or are they?

There are real vampires world of bats. Of the more than 1,400 species of bats currently described, three are known to be bats. feeds only on blood.

common vampire bat, Desmodus roundis the most abundant. These bats live in the tropical forests of Central and South America. feeds on a variety of animalsincluding tapirs, mountain lions, penguins, and nowadays mostly farm animals.

Feeding on blood is unusual for a mammal, and this has led to many unique adaptations that facilitate their unusual lifestyle. Unlike other bats vampires are moving on the groundThey switch between two different gaits to circle around their sleeping prey. Receptors in their noses that detect heat Help them find warm blood under the skin of their prey. Finally, a combination of small incisions potentially made self-sharpening teethAnd they have an anticoagulant in their saliva This allows bats to feed on unsuspecting prey.

For me As a behavioral ecologistThe scientist interested in how pathogens affect social behavior and vice versa can observe the most fascinating adaptations to a blood-feeding lifestyle in the social lives of vampire bats.

Vampire bats form mutualistic relationships

Blood is not very nutritious, and vampire bats that fail to feed will starve to death relatively quickly. If a bat returns hungry to roostthere may be others vomiting blood meal to get them through the night.

This type of food sharing occurs between related bats, such as mothers and their offspring, as well as among unrelated individuals. This observation puzzled evolutionary biologists for a long time. Why would you help someone who is not closely related to you?

Apparently vampire bats Keep track of who feeds them and respond – or not, if the other bat hasn’t been helpful in the past. In doing so, they form complex social relationships that are maintained by low-cost social investments (allogrooming), such as grooming and grooming another animal’s fur, and higher-cost social investments, such as sharing food.

These relationships are on par with relationships you’ll see in primates, and some people compare them to human friendships. There are actually some parallels.

For example, people will raise the bar when establishing new relationships with others. You start with social investments that don’t cost much—think sharing some of your lunch—and wait for the other person’s reaction. If they don’t reciprocate, the relationship may end. But if the other person reciprocates by sharing some of their dessert, for example, your next investment could be bigger. You gradually increase the stakes in the back-and-forth game until the friendship eventually warrants larger social investments, like going out of your way to drive them to work when their car breaks down.

Vampire bats do the same. When strangers are introduced, they will begin with small fur grooming interactions to test the waters. If both partners continue to reciprocate and raise the stakes, The relationship will eventually escalate. to the larger commitment of food sharing.

Relationships in sickness and health

My laboratory investigates how infections affect social behavior and relationships. Given their wide range of social behaviors and the complexity of their social relationships, vampire bats are the ideal study system for me and my colleagues.

How does being sick affect the behavior of vampire bats? How do other bats behave towards someone who is sick? How does the disease affect the formation and maintenance of social relationships?

We simulate infections in bats in our laboratory using molecules derived from pathogens to stimulate the immune response. We have repeatedly found a form of passive social distancing in which sick individuals reduce their interactions with others. allocation, social search or just spending time around others.

Importantly, these behavioral changes have not necessarily evolved to minimize the spread of the disease to others. Rather, they are part of biologists’ complex immune response. illness behaviors. comparable to someone I caught the flu and stayed at home just because they don’t dare to go out. Even if this type of passive social distancing does not evolve to prevent transmission to others, being too sick to interact with others will still reduce the spread of germs.

Interestingly, sickness behaviors can be suppressed. People do this all the time. Supposed not being able to exist He comes to work despite his illness due to various pressures. Similarly, many people have suppressed symptoms of infection to fulfill some kind of social obligation. If you have young children, you know that when everyone in your home is facing a problem, you can’t just sit back and not take care of the little ones, even if you feel terrible.

Animals are no different. they can suppress sickness behaviors when competing needs arise, such as caring for young people or defending territory. Despite their tendency to reduce social interactions with others when sick, vampire bats Sick mothers will continue to groom their children and vice versa, probably because mother-daughter relationships are so important. Mothers and daughters are often each other’s primary social contacts within vampire bat groups.

Human-bat conflict intensifies in livestock farming

Despite their many fascinating adaptations and complex social lives, vampire bats are not universally appreciated. In fact, they are considered pests in many parts of South and Central America because they can transmit the deadly rabies virus to livestock, which can cause significant economic losses.

Before humans introduced livestock into their habitats, vampire bats likely had difficulty finding food in the form of native prey species such as tapirs. Livestock has now become their main source of food. After all, why not feed on something that’s available in abundance and in the same place every night? Increases in animal abundance Comes with increases in vampire bat populationspossibly perpetuating the rabies transmission problem.

It makes sense for farmers to fight vampires, especially on small cattle herds where losing even one cow can significantly damage the farmer’s livelihood. Topically applied poisons were used in culling campaigns This so-called vampire killer is basically a mixture of petroleum jelly and rat poison. Bats are captured, the paste is applied to their fur, and the bats carry it back to their roosts, where other humans also ingest the poison during social interactions. Interestingly large scale Culling may not be very effective in reducing rabies spread.

The focus has now begun to shift towards large-scale cattle vaccinations or vaccination of vampire bats. Even researchers evaluation of infectious vaccines: they can genetically modifying herpes virusesIt is a virus that is highly prevalent in vampire bats, carries rabies genes, and inoculates a large population of vampire bats.

Whatever methods are used to alleviate vampire bat-human conflict, greater empathy for these misunderstood animals can only help. After all, if you stick your head into a hollow tree full of vampire bats—assuming you can brave the smell of digested blood—remember this: You’re looking at an intricate web of individual friendships between animals who care deeply for each other.

This article is republished from The Conversation under a Creative Commons license. Read the original article Here.