Could BATS hold the key to 'eternal life'?

Bats may hold the key to unlocking the secret to a long life because of their ability to hibernate and fight infection, experts say.

A study by the University of Maryland has found if humans were able to harness their adaptations, mankind could live up to 240 years old. 

Four bat species have been identified that have evolved ‘extreme longevity’ traits which allow them to live at least four times longer than other bats, scientists say. 

Horseshoe bats, long-eared bats, the common vampire bat and at least one mouse-eared bats live at least four times longer as mammals of a similar size.   

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Four bat species have been identified that have evolved ‘extreme longevity’ traits which allow them to live at least four times longer than other bats, scientists say. If this superior lifespan was applied to humans, it would be the equivalent of a modern humans living up to 240 years

By studying the evolutionary traits of most known bats species, scientists found that those which spent more time hibernating or had the ability to conserve energy more effectively could live up to eight times longer. 

Longevity is often correlated to body size in animals, with larger species generally living longer than smaller ones.

An African elephant can live as long as 70 years, while a common house mouse typically lives only one to three years.

Humans are considered relatively long-lived animals, tending to live about four times longer than most other mammals when adjusted for size.

But the longevity of a bat is even more astounding given their relatively small size.  

Some bats can live for 40 years – eight times longer than similarly sized mammals. 

Professor Gerald Wilkinson at University of Maryland and lead author of the latest study, said: ‘If we lived as long as bats, adjusted for size, we could live 240 years.

‘Everybody wants to know how these animals can live so long. This kind of work can help us get to the answers.’  

The team analysed traits that were known to correlate with longevity: body size, cave use and hibernation, as well as those not previously considered, such as size differences between males and females. 

Professor Wilkinson added: ‘Of the lineages of bats that live a long time, three of them are hibernators and one of them is the vampire bat,’ 

‘The vampire bat is very unusual for a mammal in that it can let its body temperature rise and fall throughout the day.

‘This ability allows a vampire bat to conserve energy if it fails to obtain a blood meal. Scientists have previously suggested that the ability to tolerate variations in body temperature may enable some mammals to fight infection better than those without that ability. 

‘This happens to a limited extent in humans when the immune system attempts to kill a virus or bacterial infection by raising body temperature and causing a fever.

Horseshoe bats, long-eared bats, the common vampire bat and at least one mouse-eared bats live at least four times longer as mammals of a simialr size.

Bat species in which males are larger than females have shorter life spans than those in which both genders are the same size, or even were males are smaller than females. 

In the majority of bat species, females are larger than males, but in some tropical bat species, males are larger than females. 

Among those species where the males were larger, competition for females may have led to male-on-male aggression that favoured the evolution towards a larger male body size.

While this would have been advantageous for males seeking mates initially, sexual conflict might also have led to greater mortality of male bats and over time, may have led to shorter species life spans.  

Professor Wilkinson said: ‘Scientists are very interested in finding closely related species in which one is long lived and one is short lived, because it implies that there has been some recent change to allow one species to live longer. 

 The full report was published in Biology Letters.