Science - USA (2020-02-07)

CREDITS: (TOP TO BOTTOM) LI

ET AL.;

ADAM RONAN/ECOFOR

SCIENCE sciencemag.org

high magnetoelectric coupling

(see the Perspective by Zhou

and Han). An applied magnetic

field strains the material, which

changes its electrical proper-

ties. The required field is much

lower than other magnetoelec-

tric materials, and this work

highlights the potential for using

molecular materials in devices.

—BG

Science, this issue p. 671;

see also p. 627

POLLINATOR DECLINE

Increasing temperatures

and declines

One aspect of climate change

is an increasing number of days

with extreme heat. Soroye et

al. analyzed a large dataset of

bumble bee occurrences across

North America and Europe

and found that an increasing

frequency of unusually hot days

is increasing local extinction

rates, reducing colonization and

site occupancy, and decreasing

species richness within a region,

independent of land-use change

or condition (see the Perspective

by Bridle and van Rensburg). As

average temperatures continue

to rise, bumble bees may be

faced with an untenable increase

in frequency of extreme tem-

peratures. —SNV

Science, this issue p. 685;

see also p. 626

GPCR SIGNALING

A biased position

for receptors

G protein–coupled receptors

(GPCRs) are the largest class

of druggable receptors in the

human proteome and can have

multiple downstream signal-

ing partners. Sanchez-Soto et

al. studied how changes in the

ligand-binding site of GPCRs

ORGANIC CHEMISTRY

Synthesis of Taxol’s

complicated cousin

Propellane molecules con-

tain three rings that all share

a common edge, thereby

collectively resembling a

propeller. Canataxpropellane,

a yew-derived natural product

related to the cancer drug Taxol,

is unusual in that it has two

RESEARCH

Water-selective zeolite

nanochannels

Li et al.,p. 667

different propellane motifs in its

backbone. Schneider et al. report

a chemical synthesis of this

intricate compound in under 30

steps. Key features of the route

include a Diels-Alder reaction

rendered asymmetric by intro-

duction of a chiral silyl auxiliary,

followed by a photochemical

cycloaddition to establish the

cyclobutane core. —JSY

Science, this issue p. 676

MULTIFERROICS

Major-league

magnetostriction

Magnetoelectric materials

polarize in response to either

electric or magnetic fields,

making them attractive for

data-storage applications.

Long et al. discovered a

ytterbium-based molecular

magnetoelectric material with

Edited byMichael Funk

IN SCIENCE JOURNALS

ECOLOGY

Lagging recovery for tropical forests

T

ropical forest aboveground carbon (AGC) stocks have yet to recover from the extremely hot

and dry weather associated with the 2015–2016 El Niño event. Wigneron et al. used low-

frequency microwave satellite data to monitor AGC changes from 2014 to 2017. By the end of

2017, AGC stocks had not reached 2014 predrought levels and continued to decline in some

areas. The slow rate of recovery could be due, in part, to enhanced forest mortality and/or

unaccounted deforestation and degradation, specifically in African humid forests. Such continuity

in long-term records may improve understanding of climate change on ecosystems. —SN

Sci. Adv. 10.1126/sciadv.aay4603 (2020).

7 FEBRUARY 2020 • VOL 367 ISSUE 6478 637

Wildfires scorched Amazonian forests during the 2015–2016 El Niño.

Some areas of the tropics around the world are failing to recover.

Published by AAAS