5
10
22
26
5 STORY ONE
s Rain and fire cause rapid
shifts between savanna and
forest
8 GENES & CELLS
s Stem cells made using human
eggs and adult cells
s Body clocks outside the brain
may contribute to disease
s In death, 115-year-old woman
shares her genetic secrets
s Double dose of gene may have
yielded bigger brain
10 ATOM & COSMOS
s Speedy neutrinos under fire
s ALMA’s first images
s Asteroid’s mountain second
only to Mars’ Olympus Mons
s Saturn’s rings hold ripples
from past comet
12 EARTH
s Europeans’ New World
arrival may have altered the
climate
s An ancient moth’s true colors
13 HUMANS
s Early peoples made their way
to Asia more than once
14 BODY & BRAIN
s Brain’s adjustments to
hearing loss lead to tinnitus
s Painkillers may boost
miscarriage risk
Features
16 LIKE A BOLT FROM ABOVE
COVER STORY: Encouraging
lightning strikes is helping
scientists understand the
commonly observed, yet still
mysterious, electric flashes.
By Alexandra Witze
22 BEWARE THE LONG TAIL
Poring over economic data
from a physicist’s perspective
suggests that Wall Street’s ways
of estimating risk are in need of
some changes.
By Rachel Ehrenberg
26 LOPPED OFF
With top predators pulled from
their food webs, researchers
observe unexpected effects
coursing through terrestrial
and marine ecosystems.
By Nadia Drake
Departments
2 FROM THE EDITOR
4 NOTEBOOK
30 BOOKSHELF
31 FEEDBACK
32 FROM THE ARCHIVE
Treating pneumonia with olive
oil sounds strange, but the idea
showed signs of early scientific
savvy.
