| Click for the Finfacts Ireland Portal Homepage |

Finfacts Business News Centre

 Irish Economy
 EU Economy
 US Economy
 UK Economy
 Global Economy
 Asia Economy


How to use our RSS feed

Follow Finfacts on Twitter

Web Finfacts

See Search Box lower down this column for searches of Finfacts news pages. Where there may be the odd special character missing from an older page, it's a problem that developed when Interactive Tools upgraded to a new content management system.


Finfacts is Ireland's leading business information site and you are in its business news section.


Finfacts Homepage

Irish Share Prices

Euribor Daily Rates

Irish Economy

Global Income Per Capita

Global Cost of Living

Irish Tax - Income/Corporate

Global News

Bloomberg News

CNN Money

Cnet Tech News


Irish Independent

Irish Times

Irish Examiner

New York Times

Financial Times

Technology News




Content Management by interactivetools.com.

News : Global Economy Last Updated: Mar 8, 2013 - 9:11 AM

Most mortality reduction since 1900 - - in 4 of 8,000 human generations
By Michael Hennigan, editor and founder of Finfacts
Mar 8, 2013 - 9:04 AM

Email this article
 Printer friendly page
Source: Commission on Growth and Development, 2008

Life expectancy is increasing in most countries and has exceeded 80 in several, as low-mortality nations continue to make progress in averting deaths. The bulk of the mortality reduction has occurred since 1900 and has been experienced by only about 4 of the roughly 8,000 human generations that have ever lived. Moreover, mortality improvement in humans is on par with or greater than the reductions in mortality in other species achieved by laboratory selection experiments and endocrine pathway mutations. Researchers say this observed plasticity in age-specific risk of death is at odds with conventional theories of ageing.

The study by researchers at the GermanMax Planck Institute for Demographic Research, published in the Proceedings of the National Academy of Sciences of the United States, investigated data at Swedish and Japanese men - - from two countries with the longest life expectancies today. It concluded that their counterparts in 1800 would have had lifespans that were closer to those of the earliest hunter-gatherer humans than they would to adult men in both countries today.

The primitive hunter gatherers, at age 30, had the same odds of dying as a modern Swedish or Japanese man would face at 72.

Why do we age?According to classical evolutionary theory, ageing evolved because the selective forces of nature diminish as age increases. Annette Baudisch and James W. Vaupel, institute scientists, suggest that we may have to find an alternative explanation to understand why we age, and they presented their argument in a November 2012 issue of 'Science,' a US magazine.

If decreasing selection pressure were the actual reason for the evolution of ageing, then all species should be equally affected by these declining evolutionary forces and mortality and fertility in all animals should display patterns over age that are typical for ageing, i.e. mortality should rise and fertility should fall. “The data paint a completely different picture,” said author Annette Baudisch. Although younger adult ages are generally subject to higher selection pressure than later ages for both humans and animals, there are species such as the desert tortoise that experience decreasing mortality over adult ages. For the freshwater polyp hydra, the risk of dying at any age is the same over the entire lifespan.

“We have to approach an explanation for the ageing process differently in order to close this gap between theory and data,” Baudisch said.

An example of an alternative explanation is the so-called “allocation theory,” typically applied in the field of life history biology as well as in economics. The theory assumes that, because resources are limited, it is important that they are used wisely. In economics these resources may include, for example, labour, capital, and raw materials. For a living organism, essential resources include water, light, and nutrients. The resources can be used to produce offspring that will preserve the animal’s genetic lineage, or they can be used to secure the organism’s own survival.

“Every organism has a difficult decision to make about how best to use these resources at each stage of life,” Baudisch said. In making these decisions, the organism faces conflicting goals. Where is it better to invest: in survival or in reproduction? Both factors are essential to “evolutionary fitness.”In most cases they cannot be maximized simultaneously. The consequences of these decisions can vary greatly from life form to life form. The freshwater polyp hydra, for example, can increase the number of offspring it produces without noticeably affecting its own chances of survival. But for other species, like for mammals, an increase in fertility is associated with substantial additional costs,which can affect not only the survival chances of each individual juvenile, but also the well-being of the adult animals.

“To better understand ageing, we first have to learn more about how conflicts between the goals of growth, survival, and reproduction play out among various animal and plant species,” Baudisch said. It is only by understanding these processes that we can one day determine which factors are responsible for the increase in mortality with age among humans, and which factors have contributed to the dramatic increase in human life expectancy over the past century. 

Finfacts 2007:The National Geographic and IBM's Genographic Project: Charting the migratory history of the human species

Max Planck Institute for Demographic Research's summary of the research

Since the species evolved 200,000 years ago in Africa, there have been some 8,000 generations of Homo sapiens. Over the course of human evolution, life expectancy has risen considerably. The greatest "jump" in longevity in humans, however, has occurred in the last 100 years within only four generations: Since 1840, the life expectancy of a newborn baby in a Western industrialised nation has risen by approximately 3 months per year. This trend continues today and is surprisingly constant. There is currently no clear sign that this trend of increasing life expectancy has reached its upper limit. In the past, many studies on human mortality focused primarily on the economic and health-related consequences of an ageing society. Only rarely has the issue been discussed in a broad evolutionary context. "Yet it is precisely this which is so fascinating, especially for research into ageing," says Oskar Burger from the Max Planck Institute for Demographic Research in Rostock. In his study he was able to show how biologically unique the latest development in human mortality actually is.

"To carry out such a comparative study, the primary requirement is a ‘baseline’ with which you can compare the various stages of human mortality," explains Oskar Burger. "Ideally, this baseline should reflect the typical or average mortality pattern experienced by humans during their existence." By far the longest period of human existence has been spent as hunter-gatherers in small groups. "Thanks to anthropological fieldwork, we have a very good average mortality profile for hunter-gatherers living today, which we used as our standard," says Burger. The scientists compared this baseline with various human populations, including the populations of Sweden and Japan, both of which currently have particularly high life expectancy, as well as a group of slaves who lived in Trinidad in the 19th century, who had exceptionally low life expectancy.

As expected, the mortality of the slaves in all age groups was higher than that of the hunter-gatherers, who ranked somewhere in the middle. The mortality of Swedes in 1800 and 1900 was still very similar to that of the hunter-gatherers, while the modern populations of Sweden and Japan had by far the lowest mortality. "Yet the biggest surprise came when we included the data for wild chimpanzees in our analysis," says Oskar Burger. "The mortality profile of the hunter-gatherers was significantly closer to that of the chimpanzees than to that of the modern populations in Sweden and Japan." Thus, the risk of death for a Swede living today is over 100-times lower than for a hunter-gatherer, while the mortality of the same hunter-gatherer is only 10-times lower than that of a wild chimpanzee.

"These results indicate that just the last 100 years of modern development have caused the mortality rates of humans to drop more dramatically than they did during the evolution of a chimpanzee-like ancestor into Homo sapiens", states Oskar Burger.

The scientists also compared the profiles of humans with those of laboratory animals specifically bred to live longer using a whole variety of techniques such as dietary modification and genetic manipulation. What they discovered was that even when the evolution of these species was provoked artificially, very few of the attempts achieved a reduction in mortality per generation equal to or exceeding that seen in the most recent evolution of humans since 1900. "The reduction in human mortality over the past century really is biologically unique. No other species has experienced anything like it," says Oskar Burger. Genetic changes within only four generations can be virtually excluded as the cause of the drop, which is probably due almost solely to environmental factors such as improved nutrition and medical care. "We do believe, however, that other species could in principle achieve comparable reductions in mortality. In future we want to extend our research to other taxa, primarily primates and other mammals. This will enable us to better estimate the plasticity of human mortality and provide a biological perspective," says Burger.

The planet's population has now passed 7 billion. But its growth will start to slow:

Related Articles
Related Articles

© Copyright 2011 by Finfacts.com

Top of Page

Global Economy
Latest Headlines
Strong Swiss franc gloom deepens for exporters
Global investors shift focus to China; EM outflows surge to $1tn in 13 months
Global oil glut will continue into 2016
Stable growth momentum in OECD area but slowing expected in China
Prices for major food commodities in July lowest since September 2009
Global manufacturing in July weakest level in two years
US, China and UK lead top 25 target countries for foreign direct investment
Budget surpluses rare in developed countries from 1980s; Italy, France, Greece had none in 60 and 40 years
Singapore, London and Shanghai top cities for new FDI projects in 2014; Dublin in 11th place
Exchange rates shuffle as Dublin ranked 49th most expensive city; Paris at 46; Berlin at 105
Western consumer groups under pressure in China and India
Developing countries facing “structural slowdown” likely to last for years
OECD BEPS Tax Project: Amazon books UK sales in UK; Australia proposes up to 100% in penalties
Emerging Markets Index falls to 12-month low in May as manufacturing contracts
US and world economies slowing in 2015 — OECD
Global manufacturing production rose slightly in May; Trade flows weak
GDP growth in OECD area slowed to 0.3% in the first quarter of 2015
Only one quarter of workers worldwide have stable employment contracts
Automatic Exchange of Tax Information: OECD says countries won't be able to game system
Gates Foundation loses in Swiss family's shares coup
Minimum wage levels in OECD countries
Brent oil benchmark over $68 a barrel - up almost 50% in 2015
Global growth slows and manufacturing dips to 21-month low
Family-controlled firms dominate European business
Top 10 of world’s 250 largest consumer products companies account for 30% of sales
Nine of world's 20 fastest growing economies in Africa
Globalisation maybe stalling as trade growth remains weak
Global growth prospects uneven across major economies says IMF
Emerging markets growth lowest since 2009; Global growth at 30-year average
China's economic rebalancing hitting Latin American economies
New York, London, HK & Singapore top global financial centres index; Dublin recovers
Global growth in modest expansion from low oil prices/ monetary easing says OECD
Composite leading indicators point to positive change in growth momentum in the Eurozone
Global labour market trends portend paradise for some but uncertainty for many workers
Vienna remains top of World Quality of Living Rankings in 2015; Dublin at 34
Zurich and Geneva overtake Singapore to become world's most expensive cities
HSBC Switzerland and Falciani: How it happened
Global economic power to continue shift from advanced economies
Global food price index falls in January; Cereal output set for record
Global debt has risen $57tn or 17% of world GDP since 2007