Data recorded by the Cincinnati Zoo helped a new Species360 Conservation Science Alliance study challenging evolutionary theories of aging in turtles and tortoises! In the study, data scientists investigated evolutionary aging theories in tortoises and turtles using data from the Species360 Zoological Information Management System (ZIMS).
We are excited and proud that the data our scientists and keepers have recorded from the turtle and tortoise animal ambassadors at the Cincinnati Zoo is helping researchers better understand aging in these species.
Even though humans live longer lives compared to their historical counterparts, we cannot escape the inevitability of aging. However, testudines – the order to which tortoises and turtles belong – may buck this trend by following a different pattern of aging compared to humans and other species.
In a new study published in the journal Science, researchers used data contributed by Cincinnati Zoo in collaboration with other zoos and aquariums to examine 52 species of turtles and tortoises. The data recorded by Cincinnati Zoo & Botanical Garden in ZIMS enabled researchers to discover that, unlike humans and other species, turtles and tortoises defy common evolutionary theories and may reduce the rate of aging in response to improvements in environmental conditions.
Evolutionary theories of aging predict that all living organisms weaken and deteriorate with age (a process known as senescence) – and eventually die. Now, using data captured by Cincinnati Zoo and others, researchers from the Species360 Conservation Science Alliance and the University of Southern Denmark show that certain animal species, such as turtles and tortoises, may exhibit slower or even absent senescence when their living conditions improve.
Out of 52 turtle and tortoise species, 75% show extremely slow senescence, while 80% have slower senescence than modern humans.
“We find that some of these species can reduce their rate of aging in response to the improved living conditions found in zoos and aquariums, compared to the wild,” said study co-author, Prof. Dalia Conde, Species360 Director of Science, Head of the Species360 Conservation Science Alliance. “In addition, modern zoological organizations play an important role in conservation, education and research, and this study shows the immense value of zoos and aquariums keeping records for the advancement of science.”
Turtles keep growing after sexual maturity
Some evolutionary theories predict that senescence appears after sexual maturity as a trade-off between the energy an individual invests in repairing damages in its cells and tissues and the energy it invests in reproduction, so its genes are passed to the next generations. This trade-off implies, among other things, that, after reaching sexual maturity, individuals stop growing and start experiencing senescence, a gradual deterioration of bodily functions with age. Theories predict that such trade-offs are unavoidable, and thus senescence is inevitable. In fact, this prediction has been confirmed for several species, particularly mammals and birds.
However, organisms that keep growing after sexual maturity, such as turtles and tortoises, are believed to have the potential to keep investing in repairing cellular damages and are thus thought to be ideal candidates for reducing and even avoiding the harmful effects of aging.
“It is worth noting that the fact that some species of turtle and tortoise show negligible senescence does not mean they are immortal; it only means that their risk of death does not increase with age, but it is still larger than zero,” said another of the researchers behind the study, Dr. Fernando Colchero, Principal Statistical Analyst, Species360 Conservation Science Alliance, and Associate Professor at the Department of Mathematics and Computer Science, University of Southern Denmark.
Zoo Turtles and Tortoises Helping Their Wild Counterparts
Using ZIMS Survival, Reproduction, and Growth Reports to help manage ex situ populations Zoo, conservation, and wildlife experts will use the ZIMS reports to help determine whether a population is healthy, and how to best sustain the well-being of individuals and groups. This is essential to managing “ex situ” populations residing in wildlife refuges, marine reserves, zoos, aquariums, and other institutions.
“Wildlife cared for by zoological institutions often represent the only assurance that a species may survive when populations decline or become extinct in the wild,” said Conde. “Reintroducing species like the Iberian lynx and the California condor are examples of what can be achieved through collaborative efforts. But as extinctions rise, we need better insight to the species we are working to save. This is our focus, and these lifecycle reports are a critical step forward,” said Conde.
Conservation leaders and species advocates will use the new reports to help manage assurance populations for species facing extinction in the wild. When threats such as disease, poaching, or encroachment are reduced or removed from natural habitats, assurance populations residing in protective care are critical to reintroducing species in the wild.