Featured Research

from universities, journals, and other organizations

Living fast but dying older is possible -- if you're a sheep

Date:
February 16, 2011
Source:
Wiley-Blackwell
Summary:
Modern humans may live longer than hunter gatherers, chimpanzees, mountain sheep or the European robin, but what does that tell us about how we age relative to other species? Not much, according to new research, which looks at a new way of comparing how different species age.

Mountain sheep. According to Dr Annette Baudisch of the Max Planck Institute for Demographic Research in Rostock, Germany, current methods of comparing patterns of ageing are limited because they confound two different elements of ageing -- pace and shape.
Credit: iStockphoto/Don Wilkie

According to Dr Annette Baudisch of the Max Planck Institute for Demographic Research in Rostock, Germany, current methods of comparing patterns of ageing are limited because they confound two different elements of ageing -- pace and shape.

"Some organisms live a short time, others live a long time. This is the pace of ageing. Short-lived species have a fast pace of ageing, and long-lived species have a slow pace of ageing. Pace describes how quickly the clock of life ticks away. For humans it ticks slowly, for small songbirds like the robin it ticks very fast," explains Dr Baudisch.

By contrast the shape of ageing describes how much mortality -- the risk of dying -- changes with age. One way of measuring the shape of ageing is the 'ageing factor'. For example, the common swift has an ageing factor of 2, meaning mortality doubles during its adult life, compared with modern humans, who have an ageing factor that exceeds 2000.

"At the age of 15, only 2 out of 100,000 girls in Sweden die, but one out of every two women aged 110 will die. This large difference in mortality at the beginning and end of adult life means that for humans the shape of ageing is steep, whereas in other species like the common swift it is shallow. And in some species the risk of death can even fall with age, with older individuals having the least risk of dying. This seems to be the case for the desert tortoise, and for alligators or crocodiles."

Using data for 10 different groups of animals from herring gull, European robin, common swift and lake sturgeon to Dall mountain sheep, African buffalo, wild and captive chimpanzees, hunter-gatherers and modern humans (Swedish women), Dr Baudisch classified how each species aged in terms of pace and shape of ageing.

Of the species she analysed, Dr Baudisch found that although modern humans are the longest-lived, they also age most strongly.

Adult life expectancy for Swedish women (that is the remaining life expectancy after reaching maturity) is about 70 years, whereas a robin's adult life lasts just 1.7 years. But over that adult lifespan, ageing is so strong in the human that the ageing factor is 2132, but for the robin only about 2.

"Comparing robins with Swedish women, humans have a slow pace of ageing whereas the robin's is fast, so in terms of length of life the humans are doing best. But if we look at the impact ageing has on death rate the robin wins. Its shape of ageing is fairly flat whereas the humans' is steep, indicating that death rates increase markedly with age," she says.

Dr Baudisch's results have important implications for evolutionary biology and the study of ageing: "We need to compare species to understand how evolution has shaped the biology of ageing in different species, but current methods of comparing patterns of ageing across species are limited because they confound the pace and shape of ageing. Not accounting for this difference can lead to incorrect conclusions about which species age more than others."

"Separating pace from shape of ageing gives a clearer picture of the characteristics of ageing. It could reveal that certain species are very similar to each other in terms of their shape of ageing, species that we would maybe never have grouped together. Ultimately, this should help us identify the determinants of ageing -- the characteristics that determine whether death rates goes up or down with age and reveal species that can successfully avoid ageing," she says.

In more everyday terms, her results might make us re-think common expressions, such as "live fast, die young." As dying young in Dr Baudisch's terms corresponds to a small ageing factor and dying old to a large one, "live fast, die young" only applies to some short-lived species.

Robins live fast and die young, but even though Dall mountain sheep only live for around 4.2 years, their ageing factor is 7.

"Not all species with short lives live fast and die young. Robins do, but mountain sheep do things differently. They also live pretty fast but die older. From the data I have, it seems that live fast die young is only one option; you can also live fast and die older, or live slower and die young, or live slow and die old. There might be every combination in nature. That's something we need to find out in the future with better data."


Story Source:

The above story is based on materials provided by Wiley-Blackwell. Note: Materials may be edited for content and length.


Journal Reference:

  1. Annette Baudisch. The pace and shape of ageing. Methods in Ecology and Evolution, 2011; DOI: 10.1111/j.2041-210X.2010.00087.x

Cite This Page:

Wiley-Blackwell. "Living fast but dying older is possible -- if you're a sheep." ScienceDaily. ScienceDaily, 16 February 2011. <www.sciencedaily.com/releases/2011/02/110214201840.htm>.
Wiley-Blackwell. (2011, February 16). Living fast but dying older is possible -- if you're a sheep. ScienceDaily. Retrieved September 2, 2014 from www.sciencedaily.com/releases/2011/02/110214201840.htm
Wiley-Blackwell. "Living fast but dying older is possible -- if you're a sheep." ScienceDaily. www.sciencedaily.com/releases/2011/02/110214201840.htm (accessed September 2, 2014).

Share This




More Plants & Animals News

Tuesday, September 2, 2014

Featured Research

from universities, journals, and other organizations


Featured Videos

from AP, Reuters, AFP, and other news services

We've Got Mites Living In Our Faces And So Do You

We've Got Mites Living In Our Faces And So Do You

Newsy (Aug. 30, 2014) A new study suggests 100 percent of adult humans (those over 18 years of age) have Demodex mites living in their faces. Video provided by Newsy
Powered by NewsLook.com
Washington Wildlife Center Goes Nuts Over Baby Squirrels

Washington Wildlife Center Goes Nuts Over Baby Squirrels

Reuters - US Online Video (Aug. 30, 2014) An animal rescue in Washington state receives an influx of orphaned squirrels, keeping workers busy as they nurse them back to health. Rough Cut (no reporter narration). Video provided by Reuters
Powered by NewsLook.com
Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Experimental Ebola Drug ZMapp Cures Lab Monkeys Of Disease

Newsy (Aug. 29, 2014) In a new study, a promising experimental treatment for Ebola managed to cure a group of infected macaque monkeys. Video provided by Newsy
Powered by NewsLook.com
Killer Amoeba Found in Louisiana Water System

Killer Amoeba Found in Louisiana Water System

AP (Aug. 28, 2014) State health officials say testing has confirmed the presence of a killer amoeba in a water system serving three St. John the Baptist Parish towns. (Aug. 28) Video provided by AP
Powered by NewsLook.com

Search ScienceDaily

Number of stories in archives: 140,361

Find with keyword(s):
Enter a keyword or phrase to search ScienceDaily for related topics and research stories.

Save/Print:
Share:

Breaking News:
from the past week

In Other News

... from NewsDaily.com

Science News

Health News

Environment News

Technology News



Save/Print:
Share:

Free Subscriptions


Get the latest science news with ScienceDaily's free email newsletters, updated daily and weekly. Or view hourly updated newsfeeds in your RSS reader:

Get Social & Mobile


Keep up to date with the latest news from ScienceDaily via social networks and mobile apps:

Have Feedback?


Tell us what you think of ScienceDaily -- we welcome both positive and negative comments. Have any problems using the site? Questions?
Mobile: iPhone Android Web
Follow: Facebook Twitter Google+
Subscribe: RSS Feeds Email Newsletters
Latest Headlines Health & Medicine Mind & Brain Space & Time Matter & Energy Computers & Math Plants & Animals Earth & Climate Fossils & Ruins