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Abstract The dwarf lemurs (Cheirogaleusspp.) of Madagascar are the only obligate hibernators among primates. Despite century‐old field accounts of seasonal lethargy, and more recent evidence of hibernation in the western fat‐tailed dwarf lemur (Cheirogaleus medius), inducing hibernation in captivity remained elusive for decades. This included the Duke Lemur Center (DLC), which maintains fat‐tailed dwarf lemurs and has produced sporadic research on reproduction and metabolism. With cumulative knowledge from the field, a newly robust colony, and better infrastructure, we recently induced hibernation in DLC dwarf lemurs. We describe two follow‐up experiments in subsequent years. First, we show that dwarf lemurs under stable cold conditions (13°C) with available food continued to eat daily, expressed shallower and shorter torpor bouts, and had a modified gut microbiome compared to peers without food. Second, we demonstrate that dwarf lemurs under fluctuating temperatures (12–30°C) can passively rewarm daily, which was associated with altered patterns of fat depletion and reduced oxidative stress. Despite the limitations of working with endangered primates, we highlight the promise of studying hibernation in captive dwarf lemurs. Follow‐up studies on genomics and epigenetics, metabolism, and endocrinology could have relevance across multidisciplinary fields, from biomedicine to evolutionary biology, and conservation.
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This content will become publicly available on February 1, 2026
Food deprivation is associated with telomere elongation during hibernation in a primate
Telomeres, the protective ends of chromosomes, progressively shorten due to incomplete mitotic replication and oxidative stress. In some organisms, transient telomere elongation may occur, for example, when individuals have an energy surplus to counter stress-induced life events or when elongating telomeres is a last chance to increase fitness. Mammalian hibernators are good models to test telomere dynamics, as they cycle between prolonged bouts of metabolic depression (torpor) punctuated by short surges to euthermia (arousals). We studied captive fat-tailed dwarf lemurs (Cheirogaleus medius), strepsirrhine primate hibernators, that were food-deprived (n= 8) or fed daily (n= 7) during hibernation (4.5 months). We compared telomere lengths, assayed via qPCR from oral swabs, at five strategic time points that span a full year. Food-deprived subjects underwent multi-day torpor/arousal cycles, lost considerable body mass and elongated telomeres during hibernation but shortened them upon emergence. In contrast, food-provisioned subjects ate daily, lost body mass more slowly, underwent shallower and shorter torpor bouts and experienced little change in telomere lengths during the same periods. Our results highlight a complex relationship between telomere dynamics, energy balance and torpor expression. Further investigation is warranted to elucidate the regulation of protective mechanisms in these primate hibernators.
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- Award ID(s):
- 2314898
- PAR ID:
- 10617879
- Publisher / Repository:
- Biology Letters
- Date Published:
- Journal Name:
- Biology Letters
- Volume:
- 21
- Issue:
- 2
- ISSN:
- 1744-957X
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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