Brandt's bats (Myotis brandtii) can live up to 41 years old and possibly older. That may not seem like a long time to you, but usually tiny animals have a short lifespan. This is not a rule in science, but generally small animals live fast and die quick. Example: common house mice live two to three years and weigh 40 to 45 grams, whereas Galapagos tortoises weight between 113 and 227 kilograms (that's 250 to 500 pounds) and live well over 100 years with some up to 170 years old. Now let's take a look at Brandt's bat:- They weigh 4 to 8 grams.- They live over 20 years.- One little guy lived to be over 41 years old. So how do these little bats live for so long? Spoiler alert: we're not sure. Here is what we know so far:- The key may be in their genes. The insulin-like growth factor 1 and receptor growth hormone receptor genes are altered. These genetic changes are associated with increased longevity in laboratory mammals and other long-lived animals. - Their telomeres do not shorten with age. Telomeres protect the ends of chromosomes and usually shorten as an animal ages, so there's speculation that this may be another tool by which Brandt's bats live longer than expected.- They're adorable and magic. Brandt's bat (Myotis brandtii) Photo Credit: Manuel Ruedi, Natural History Museum of Geneva References:Andrej J. Podlutsky, Alexander M. Khritankov, Nikolai D. Ovodov, Steven N. Austad; A New Field Record for Bat Longevity, The Journals of Gerontology: Series A, Volume 60, Issue 11, 1 November 2005, Pages 1366–1368, https://doi.org/10.1093/gerona/60.11.1366.Seim, I., Fang, X., Xiong, Z., Lobanov, A. V., Huang, Z., Ma, S., ... & Gerashchenko, M. V. (2013). Genome analysis reveals insights into physiology and longevity of the Brandt’s bat Myotis brandtii. Nature communications, 4, 2212.Foley, N. M., Hughes, G. M., Huang, Z., Clarke, M., Jebb, D., Whelan, C. V., ... & Ransome, R. D. (2018). Growing old, yet staying young: The role of telomeres in bats’ exceptional longevity. Science advances, 4(2), eaao0926.