Campus Units

Ecology, Evolution and Organismal Biology

Document Type

Article

Publication Version

Accepted Manuscript

Publication Date

9-9-2019

Journal or Book Title

Functional Ecology

DOI

10.1111/1365-2435.13450

Abstract

1.The field of comparative aging biology has greatly expanded in the past 20 years. Longitudinal studies of populations of reptiles with a range of maximum lifespans have accumulated and been analyzed for evidence of mortality senescence and reproductive decline. While not as well represented in studies of amniote senescence, reptiles have been the subjects of many recent demographic and mechanistic studies of the biology of aging.

2. We review recent literature on reptile demographic senescence, mechanisms of senescence, and identify unanswered questions. Given the ecophysiological and demographic diversity of reptiles, what is the expected range of reptile senescence rates? Are known mechanisms of aging in reptiles consistent with canonical hallmarks of aging in model systems? What are the knowledge gaps in our understanding of reptile aging?

3. We find ample evidence of increasing mortality with advancing age in many reptiles. Testudines stand out as slower aging than other orders, but data on crocodilians and tuatara are sparse. Sex‐specific analyses are generally not available. Studies of female reproduction suggest that reptiles are less likely to have reproductive decline with advancing age than mammals.

4. Reptiles share many physiological and molecular pathways of aging with mammals, birds, and laboratory model organisms. Adaptations related to stress physiology coupled with reptilian ectothermy suggest novel comparisons and contrasts that can be made with canonical aging phenotypes in mammals. These include stem cell and regeneration biology, homeostatic mechanisms, IIS/TOR signaling, and DNA repair.

5. To overcome challenges to the study of reptile aging, we recommend extending and expanding long‐term monitoring of reptile populations, developing reptile cell lines to aid cellular biology, conducting more comparative studies of reptile morphology and physiology sampled along relevant life‐history axes, and sequencing more reptile genomes for comparative genomics. Given the diversity of reptile life histories and adaptations, achieving these directives will likely greatly benefit all aging biology.

Comments

This is the peer reviewed version of the following article: Hoekstra, Luke A., Tonia S. Schwartz, Amanda M. Sparkman, David AW Miller, and Anne M. Bronikowski. "The untapped potential of reptile biodiversity for understanding how and why animals age." Functional Ecology (2019), which has been published in final form at doi: 10.1111/1365-2435.13450. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions.

Copyright Owner

The Authors. Functional Ecology, British Ecological Society

Language

en

File Format

application/pdf

Available for download on Wednesday, September 09, 2020

Published Version

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