Even though humans and elephants took two different evolutionary paths almost 100 million years ago, both have somehow developed similar characteristics.
(WTIU News)
Daniella Chusyd, IU assistant professor in the Department of Environmental and Occupational Health in the School of Public Health, has been studying how elephant aging can teach us about human aging. As the second longest-living terrestrial mammal, second only to humans, elephants are capable of living up to ages similar to humans, have a cognitive memory and are reliant on their families.
Chusyd has done her most recent research in Zambia, working to establish a potential connection between early life trauma and later life health and behavior in elephants. She compared two groups of elephants, one group that randomly became orphans at a young age and the other that grew up with a complete family.
“Some of our preliminary results show in terms of behavior, we see a reduction in affiliative behavior,” Chusyd said. “There's a lot less touching between individuals or reassurance and comfort from our orphaned elephants compared to our wild elephants.”
Chusyd also found that there is no difference in cortisol levels between the two groups. Cortisol is a measure of psychological and physiological stress. The results also demonstrated higher levels of thyroid hormone, a measure of nutritional stress, in the wild elephants. With these results, she hopes to find a relationship between the thyroid hormone, seasonality and body condition.
She also hopes to further study the two groups’ social relationships, reactions to pollutants and how trauma affects their physiological responses and aging.
“You could throw a dart at the dartboard and you're good to go, it probably hasn't been done, and you can start studying it,” Chusyd said. “But it is challenging because there isn't the foundation there to lean back on: you have to build a lot of preliminary data and convince people like that this is relevant, and it makes sense, and you should invest in this line of inquiry.”
Chusyd thinks it is important to study how elephants are able to live so long without developing aging associated diseases, such as Alzheimer’s, like humans often do, because it could help humans combat the disease. Even though humans and elephants took two different evolutionary paths almost 100 million years ago, both have somehow developed similar characteristics.
“They took a different route to get to a similar destination, and so if we start to examine that route, what can we learn from it?,” Chusyd said.
Chusyd suspects elephants develop cancer at lower rates than humans because they have 20 copies of the TP53 gene, when humans only have one copy. The TP53 gene is associated with tumor growth, Alzheimer’s disease and cellular aging. The gene senses if a cell is stressed and either kills or repairs it. Since there are 20 copies of the gene, it is easier to detect DNA damage and kill the cell, avoiding cell mutation and replication.
“If we only go down one road every time, we only know what that road shows us,” Chusyd said. “There are more pieces to our puzzle to give us a fuller picture, and I think elephants are just one more puzzle piece that we have kind of been overlooking. It’s something that could be very informative to furthering our understanding of aging in general.”
