2SCIEN0CE NEWS OF THE YEAR | Humans
08
Grasping numbers without words
studies challenge theories that link language and thought
brazil’s pirahã people can’t count on using words for the number one or for any other
number to describe exact quantities, a team led by mit cognitive scientist edward
gibson suggests (SN: 7/19/08, p. 5). the denizens of the amazon rainforest are the first
group anywhere reported to lack an expression for the number one. but pirahã adults can
still identify the number of items placed in front of them by picking out a matching number of items, the team concludes.
“these results suggest that number words do not change our underlying representations of number, but instead are a cognitive technology for keeping track of the exact size
of large sets over time and in different contexts,” says study coauthor michael frank.
during testing, questions arose about whether the pirahã really possessed nonverbal
knowledge of precise amounts or simply assumed that they should place an item next
to each item set out by experimenters. gibson’s team plans to explore that possibility. in
the meantime, the researchers have found that english speakers who are temporarily distracted and unable to count perform as well as the pirahã do on tests requiring identification of up to 10 items (SN: 8/16/08, p. 12). that’s further evidence that basic numerical
competence operates nonverbally, without the need for counting terms, frank says.
This Pirahã man’s language contains no number words, researchers suggest.
Domain of the dead
An investigation of England’s
Stonehenge (shown above)
reveals that the site served as
a cemetery from its inception
nearly 5,000 years ago until
well after its large stones
were put in place 500 years
later (SN: 6/21/08, p. 13).
Shifting priorities Even the
simplest multitasking disrupts a person’s ability to
drive a car safely, scientists
show (SN: 5/10/08, p. 7).
Toddlers triumphant Studies of toddlers indicate that
basic mental capacities, such
as perceiving and exploring
objects, give rise to youngsters’ rapid grasp of object
names (SN: 8/16/08, p. 12).
Commitment-phobia
Scientists report a link
between a common gene
variant and some men’s
inability to form strong
romantic relationships and
avoid marital conflict (SN:
9/27/08, p. 12).
Hobbit wars Anthropologists
continue to debate whether
hobbits that lived on an Indonesian island about 90,000 to
12,000 years ago are a separate species, Homo floresiensis,
or just small Homo sapiens. A
study shows the hobbits display no signs of several growth
disorders that would result in
an unusually small brain (SN:
3/15/08, p. 165), (SN: 5/10/08,
p. 7), (SN Online: 8/26/08).
Deciphering DNA Researchers sequence the largest
strand to date of Neandertal
mitochondrial DNA, revealing that humans diverged
from these relatives 660,000
years ago ( SN Online: 8/7/08).
European roots A fossil jaw
and tooth found in a cave in
Spain date to between
1. 2 million and 1. 1 million
years ago, yielding the
earliest known skeletal evi-
dence of human ancestors
in Europe (SN: 3/29/08,
p. 196).
Rare mutations DNA mutations that probably disrupt
brain development occur
at relatively high rates in
people with schizophrenia,
according to two research
teams (SN: 4/5/08, p. 222).
Body-swap illusion Using a
new technique, investigators
make volunteers feel that
they’ve swapped bodies with
a mannequin or another person (SN: 12/6/08, p. 16).
clockwise from top left, Humans: e. gibson; k. smitH/mallinckrodt inst. radiology, wasH.
univ. st. louis, e. indriati, d. frayer; adam stanford, copyrigHt 2008 NATIONAL GEOGRAPHIC
Honey of a discovery An
ancient Israeli site yields the
oldest known archaeological
example of beekeeping, dating back to the time of King
David and King Solomon
(SN: 9/27/08, p. 11).
Gal gets hips A female Homo
erectus who lived in Africa
roughly 1 million years ago
had hips wide enough to bear
babies with brains nearly
as big as those of newborn
human infants, a pelvis fossil
suggests (SN: 12/6/08, p. 14).
