Telomere dynamics in Tree Swallows: exploring the effects of temperature and microbiome
Author:
Sarah Chapman ’25Co-Authors:
Jess L. Fenners, Jennifer L. Houtz, Maren N. VitousekFaculty Mentor(s):
Mark Haussmann, Biology DepartmentFunding Source:
Biology Department & NSF grant awarded to Vitousek and Haussmann (IOS-1457251)Abstract
As the climate is rapidly changing, many species are facing a more unpredictable and thus challenging environment. Particularly, frequent cold weather swells, known as cold snaps, have posed a significant thermoregulatory challenge that is suspected to shorten telomeres–the non-coding, protective, terminal caps on chromosomes–and ultimately reduce organismal lifespan. However, it is unknown how the composition of the gut microbiome affects an organism’s ability to face these thermoregulatory challenges. Here, we investigated the effect of temperature and antibiotics on telomere length in the widely distributed and tractable Tree Swallow (Tachycineta bicolor). Wild nestlings were reared in captivity from days five to twelve post-hatch under both cold (31ºC) and control (35ºC) conditions and further divided into two groups: antibiotic treated and non-antibiotic treated. Blood samples from twelve days post-treatment were analyzed using the telomere restriction fragment assay. While there was no significant temperature by antibiotic interaction, both warmer temperatures and antibiotic treatment resulted in individuals with longer telomeres. These findings suggest that more variable and colder climates early in the breeding season are likely to have a detrimental impact at the cellular level. Though we predicted that the administration of antibiotics may result in more telomere loss, the longer telomere average for the antibiotic treated nestlings suggests the connection between temperature challenges and the gut microbiome is complex and deserving of further research.