Show Summary Details
Page of

Why do organisms age? 

Why do organisms age?
Why do organisms age?

Thomas B. L. Kirkwood

Page of

PRINTED FROM OXFORD MEDICINE ONLINE ( © Oxford University Press, 2022. All Rights Reserved. Under the terms of the licence agreement, an individual user may print out a PDF of a single chapter of a title in Oxford Medicine Online for personal use (for details see Privacy Policy and Legal Notice).

date: 17 May 2022

The study of the underpinnings of ageing provides insight not only into the kinds of genetic factors that influence the ageing process, but also into the physiological mechanisms influencing ageing and longevity. Notions that ageing was necessary to create living space for future generations, or to facilitate turnover of the population, are generally unsound. Instead, ageing is thought to have its evolutionary origins in how the force of natural selection declines with age, the later portions of the lifespan being under indirect evolutionary control. The most widely supported explanation of why organisms age is the disposable soma theory. This posits that, under pressure of selection to make the best use of available resources, genomes evolved to put only enough effort into cellular maintenance to keep the individual in sound condition through the period that it might normally have been expected to survive and reproduce in ancestral, wild environments.

Access to the complete content on Oxford Medicine Online requires a subscription or purchase. Public users are able to search the site and view the abstracts for each book and chapter without a subscription.

Please subscribe or login to access full text content.

If you have purchased a print title that contains an access token, please see the token for information about how to register your code.

For questions on access or troubleshooting, please check our FAQs, and if you can't find the answer there, please contact us.