From: J. R. Molloy (jr@shasta.com)
Date: Sat Dec 08 2001 - 21:44:38 MST
DAVIS, Calif., Dec. 5 (AScribe Newswire) -- Over the years, scientists
have theorized that longer life spans among some animal species, including
humans, might be attributed to the size of their brains, protective body
features or even a superior ability to flee from predators.
Now, two University of California, Davis researchers propose that,
among
humans and other social species, a long life span is a desirable trait that
has
developed through the evolutionary process. In fact, their model of longevity
suggests that long life spans among social species offer benefits conducive to
even longer life spans in successive generations. Extension of the life span
is
a "self-reinforcing" process, they propose.
"This entirely reframes the way we consider the future of human life
expectancy," says James Carey, a UC Davis authority on biology and the
demography of aging and life span. "This model of longevity extension in
humans, combined with evidence that human life span is not fixed but is
continuing to increase in developed countries, suggests that there is every
reason to believe that human life span will continue to increase in the
foreseeable future."
Carey is a senior scholar at the Center for the Economics and
Demography
of Aging at UC Berkeley and one of four panelists who debated the future of
human life span during the recent meeting of the International Union for the
Scientific Study of Population. He and Debra Judge, a UC Davis research
ecologist, published a paper titled "Life Span Extension in Humans Is
Self-Reinforcing: A General Theory of Longevity" in a recent issue of the
scientific journal "Population and Development Review."
Long life spans, they point out, offer numerous advantages to humans
and
other animals that live in social communities rather than individually. Small
increases in longevity can be amplified in successive generations, leading to
even greater longevity.
For example, a longer life allows more opportunity for humans and other
species over time to develop the biological mechanisms that at older ages will
maintain health and repair physical flaws. Increased longevity also makes it
possible for older individuals to nurture and pass on resources to the younger
generation. And, as the life span lengthens and experience increases
efficiency, the products of the labor of the community can be reinvested among
several generations, allowing individuals to specialize in their areas of
strength, fostering innovations that, in turn, promote longer life.
Also, when the life span is extended, the number of offspring usually
decreases, allowing parents to invest more resources for a longer period in
children who are therefore more likely to survive, the researchers point out.
This decreases the physical drain on the parents, resulting in adults and
children that are healthier and longer lived.
Thus, long life breeds long life.
"This model of longevity suggests that continuing developments in
science and technology, such as organ cloning, transplantation of organs from
other animals and molecular medicine, will further equip humans to gain more
control over their environment, health and overall quality of life," says
Carey. "People increasingly will be able to make choices that will lead to
longer lives for themselves and their children."
This research project was funded by the National Institute on Aging.
http://www.ascribe.org/cgi-bin/spew4th.pl?fname=2001-12/20011205.162305.1&time
=16:50+Pacific+Time&year=2001&public=1
--- --- --- --- ---
Useless hypotheses, etc.:
consciousness, phlogiston, philosophy, vitalism, mind, free will, qualia,
analog computing, cultural relativism, GAC, Cyc, Eliza, cryonics, individual
uniqueness, ego, human values, scientific relinquishment, malevolent AI,
non-sensory experience, SETI
We move into a better future in proportion as science displaces superstition.
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