News in Brief: Humans
New World island roots
Prehistoric people who took sea voyages to an island 42 kilometers
from Californias coast laid down offshore roots by eating some.
Between about 11,500 and 3,000 years ago, residents of San Miguel
Island ate carbohydrate-rich corms energy-storage bulbs attached to
certain plant roots. Soil samples from a cave occupied by early
islanders contain corm fragments, report ethnoarchaeologist Seetha
Reddy of Statistical Research Inc. in Woodland, Calif. and
archaeologist Jon Erlandson of the University of Oregon in Eugene
in an upcoming Journal of Archaeological Science. Corms
and seafood provided a nutritious diet far from the mainland, the
team proposes. Bruce Bower
Rock, paper, copycat
Rock smashes scissors, scissors cuts paper and imitation trumps
self-interest. People ape opponents gestures in the
rock-paper-scissors game more often than expected by chance, at
least if the opponent moves first by a fraction of a second, say
psychologist Richard Cook of University College London and his
colleagues. Imitation is a lousy game strategy, since it always
produces draws, but the brain has evolved to prompt involuntary
mimicking of social partners actions, the scientists propose online
July 20 in the Proceedings of the Royal Society B. The
imitation effect was strongest for the scissors gesture, which the
researchers note is very different from the starting fist position.
Bruce Bower
Dangers less scary together
Emotional security may hinge on nonverbal cues that someone else
has our backs. Volunteers walking a cliffside path in a 3D virtual
world concentrated better and reported less anxiety when
accompanied by avatars of their real-life romantic partners that
clapped, waved and looked toward them, versus digitized partners
that looked away, say psychologist Heidi Kane of the University of
California, Los Angeles and her colleagues. Participants stayed
farther away from inattentive than from attentive virtual partners
after cliff walks, the researchers report in an upcoming
Journal of Experimental Social Psychology. Others
emotional presence matters more than their physical presence, they
conclude. Bruce Bower