The Weekly Newsmagazine of Science
Volume 156, Number 3 (July 17, 1999)
A fusion success story
Occasionally, one of the many roadblocks to controlled fusion
yields to advancing knowledge ("Fusion fuel zips to core through
back door," SN: 5/22/99, p. 327). However, we can already get
energy from fusion at a cost only slightly higher than that of
fossil fuels. There is a fusion reactor 93 million miles from
Earth. Solar heating, plus electricity from photovoltaics, wind,
and hydro, already contributes substantially to the world's energy
It's not clear if controlled fusion can ever produce energy that
is competitive with other sources. Research on solar energy and
efficient technologies will produce more energy, decades sooner,
than research on controlled fusion.
An outside line
Some think the child's skeleton in Portugal is a hybrid of Neandertal
and Homo sapiens ("Fossil
may expose humanity's hybrid roots," SN: 5/8/99, p. 295).
Others think it just is a robust child of non-Neandertal lineage.
What about the possibility that it was hybrid and sterile? This
would explain why Neandertals and non-Neandertals lived at the
same time in the Middle East in separate lines. A long period
of separate lines living in the same area would imply sterile
I was fascinated
to read in your May 8 issue that Neandertal expert Erik Trinkaus
was convinced by "the huge 'snowplow' jaw, large front teeth,
short legs, and broad chest" on a fossil that Neandertals and
Homo sapiens did some interbreeding. If that is enough to convince
him of hybridization, he did not have to look so far. Tune in
NBC television at 11:35 p.m. for a living human being showing
King of Prussia, Pa.
Ready to rumble
I found "Battle of the sexes" (SN: 5/15/99, p. 312) unreasonable.
A mammalian offspring, no matter who its father is, cannot profit
from the death or ill health of its mother prior to weaning. Death
then means the offspring will die, and ill health means the offspring
will be badly fed. However, if a promiscuous mother has offspring
in the same litter by multiple fathers, sibling rivalry makes
sense. The larger embryos and babies will win in a competition
for food, perhaps bad for the mother but good for the father,
who wants only his offspring to survive.
Highland Park, N.J.
While natural selection would not likely favor
the paternal genes that actually kill the mother during childbirth
or prevent her essential care of newborns, it could favor genes
that take mother and her embryo near that precipice. J.
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