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See Inside December 2008

Updates: Whatever Happened to Midsize Black Holes?

Also: updates on HIV's origins, Neandertal fishing and transgenic guidelines

Rules for Genetically Engineered Animals
After years of anticipation, the U.S. Food and Drug Administration released in September preliminary guidelines for genetically engineered animals [see “Does the World Need GM Foods?”; SciAm, April 2001]. The agency, which deemed that cloned meat poses no extra risk, wants to regulate engineered animals as it does drugs. Producers would have to substantiate claims and demonstrate safety. Consumer groups complain that the draft sets no provision for labeling and that safety trials can be done behind closed doors, as is the case for drug applications. Public comment on the draft ended in mid-November, and the FDA was to issue its final guidelines shortly thereafter.

No Middle Ground
Astronomers know of the giant black holes at galactic cores and the comparatively lightweight versions that form when stars collapse. But what of black holes in between? [See “Hole in the Middle”; SciAm, April 2001.] Such midsize versions now seem to be especially rare. Their best hiding places were thought to be at the centers of dense clumps of stars called globular clusters. Resembling miniature galaxies, these clusters should have matching-size black holes, scientists reasoned. A recent examination of globular cluster RZ2109, however, reveals that it possesses a small black hole. Its presence implies that RZ2109 does not have a medium black hole, which would have pulled in the small one. The findings hole up in the August 20 Astrophysical Journal Letters.
 —Charles Q. Choi

Longtime Companion
A lymph node biopsy taken in 1960 from a woman who lived in what is now Kinshasa, Democratic Republic of the Congo, contained traces of the HIV-1 genome. Comparison with existing HIV sequences suggests that HIV surfaced in 1908, pushing back by a decade an earlier estimate based on an infected blood sample collected from the same city in 1959. The finding, in the October 2 Nature, suggests that trade routes may have contributed to the emergence of the virus, which most likely originated among chimpanzees in Cameroon, hundreds of kilometers from Kinshasa. Understanding HIV’s origin could lead to better AIDS therapies [see “HIV 25 Years Later: The Big Challenges”; SciAm, November 2008].

Resourceful Neandertals
Our Ice Age cousins the Neandertals were hardly the doltish brutes that scientists once believed them to be [see “Who Were the Neandertals?”; SciAm, April 2000]. This realization has raised the question of why they lost out to Homo sapiens. Some experts have argued that H. sapiens outcompeted them by exploiting a wider variety of foods than did the Neandertals, who seemed to have subsisted mostly on large, dangerous land mammals such as woolly rhinos. But researchers writing in the September 23 Proceedings of the National Academy of Sciences USA report that Neandertals at two coastal sites in Gibraltar—Vanguard Cave and Gorham’s Cave—routinely dined on mollusks, fish, seals and dolphins for tens of thousands of years. With Neandertals apparently able to formulate hunting and gathering strategies as advanced as those of the modern humans who lived after them at these sites, the secret of H. sapiens success is more mysterious than ever.
—Kate Wong

Note: This story was originally printed with the title, "Updates".

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