You have this correlation between body mass and longevity: [the smaller the animal, the shorter the life span]. Except for bats. With a very small body size, they live much, much longer.
The Gerontology paper said longevity of more than 20 years is documented for 22 bat species and more than 30 years for six species. Studying [aging in] bats is like. That is the highest value ever reported for any mammal, including those maintained in captivity. The human longevity quotient, with a record documented life span of years, is 4. There have been some hints as to how they manage this exceptional aging. For example, bats maintain the ends of their chromosomes, preventing cells from slipping into senescence, yet they do this while managing to keep cells from growing out of control and turning cancerous.
To take a systematic look at what's going on, the researchers worked with a related species of bats that can live for over 25 years. The bats were captured, the researchers took blood samples, tagged them, and then released them. Six years later, they repeated the process, getting data for different bats and opening a window into how the bats had changed during aging. They tracked which genes were active at each time point, allowing them to track how the bats' blood cells were changing with age.
Individual bats will see changes in gene activity because they have different histories and encounter different environmental conditions the bats came from five different colonies. So the researchers looked for differences in gene activity that were present in the majority of the samples at the later date.
These were relatively small in number; the scientists estimate that only about nine percent of the total differences in gene activity are associated with aging. But within that nine percent were some genes that stood out. Most of the age-related difference could be accounted for by genes with the largest changes in activity. And these were enriched in genes involved in processes that keep cells healthy: repairing DNA damage and digesting and recycling damaged components figured prominently.
Bat Life Cycle Bats gather in large numbers to mate starting in the late summer and early fall. How Long Do Bats Live? Get rid of bugs fast. Select a pest service Wilkinson said the researchers can't say for sure how latitude impacts longevity, but their study suggests it may have to do with these bats' ability to allow their body temperature to fluctuate.
Because higher latitudes tend to require longer hibernation periods, hibernating bats must be able to adjust their body temperature, allowing it to drop significantly during hibernation and rewarm during active times.
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.
Not all adaptations extend life span, however. Identifying traits that correspond with shorter life spans is also important to understanding longevity. This study showed that bat species in which males are larger than females have shorter life spans than those in which males are the same size or smaller than females. In the majority of bat species, females are larger than males. Scientists have speculated that this could be due to the need for females to fly while pregnant and carry their young.
But in some tropical bat species, males are larger than females. Among these bats, competition for females may have led to male-on-male aggression that favored the evolution of larger male body size.
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