The Raelian Movement
for those who are not afraid of the future : http://www.rael.org
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Poor Start in Life Need Not Spell Doom in Adulthood
http://www.sciencedaily.com/releases/2010/10/101021113014.htm
ScienceDaily (Oct. 21, 2010) — Does the environment encountered early
in life have permanent and predictable long-term effects in adulthood?
Such effects have been reported in numerous organisms, including
humans.
But now a biology graduate student at the University of California,
Riverside reports that how individuals fare as adults is not simply a
passive consequence of the limits that early conditions may impose on
them. Studying how adult Trinidadian guppies (small freshwater fish)
responded to their early food conditions, Sonya Auer found that the
guppies had compensated for a poor start to life in unexpected, and
potentially adaptive, ways.
"Adult guppies were able to mitigate the potential negative effects of
early setbacks, such as poor conditions during early stages of growth
and development, by being flexible in their growth and reproductive
strategies," said Auer, who works in the laboratory of David Reznick,
a professor of biology.
Study results appear in the December 2010 issue of The American Naturalist.
To study how adult guppies responded to early food conditions, Auer
raised two batches of juvenile guppies separately on low and high food
levels in the lab. Once they reached sexual maturity, she switched
half of the females from each juvenile food level to the opposite
adult food level and kept the other half on the same ration trajectory
received during the juvenile stage.
She then measured adult responses in somatic growth, reproductive
rate, reproductive investment, number of offspring, offspring size and
female body condition to juvenile growth history, how these responses
changed with age and how they affected overall reproductive success
under low and high adult food conditions.
She found that, as predicted, females reared as juveniles on low food
matured at a later age, at a smaller size and with less energy
reserves than females reared on high food as juveniles.
"Entering adulthood, they were subsequently limited in the amount of
time they had to produce babies, the number of babies they could carry
at one time, and the amount of energy they could invest in
reproduction," she said. "However, females reared on low food were
able to replenish their fat reserves, increase their growth rate to
make up for their small body size, and produce more babies to
compensate for their delayed maturity. The end result was that they
were able to achieve the same reproductive success as females reared
on high food, regardless of the quality of the adult environment."
Next, Auer plans to study how guppy growth and reproductive strategies
respond to seasonal variation in food availability in the wild.
Female guppies used in the experiment were the offspring of first
generation descendents of fish collected in 2008 from a downstream,
high predation site on the Aripo River in the Northern Range Mountains
of Trinidad.
The research was supported by a University of California Dissertation
Research grant and a National Science Foundation Graduate Research
Fellowship to Auer, and a National Science Foundation grant to
Reznick.
Story Source:
The above story is reprinted (with editorial adaptations by
ScienceDaily staff) from materials provided by University of
California -- Riverside.
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"Ethics" is simply a last-gasp attempt by deist conservatives and
orthodox dogmatics to keep humanity in ignorance and obscurantism,
through the well tried fermentation of fear, the fear of science and
new technologies.
There is nothing glorious about what our ancestors call history,
it is simply a succession of mistakes, intolerances and violations.
On the contrary, let us embrace Science and the new technologies
unfettered, for it is these which will liberate mankind from the
myth of god, and free us from our age old fears, from disease,
death and the sweat of labour.
Rael
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