Your initiative to address the
issue of sexism in publishing
is laudable (Nature 491, 495;
2012). But scientific editors may
be biased in other ways that
influence the publication process
— and they are not in the best
position to recognize and correct
their own biases.
An independent, external
assessment body that regularly
evaluates editorial practices
across scientific journals might
be the answer. This would
promote transparency and
reassure authors that their work
is being dealt with fairly. An
‘objectivity factor’ resulting
from such an assessment could
become a key metric of journal
performance, alongside its
Boyan K. Garvalov University of
Implicit bias against women
(Nature 491, 495; 2012) has a
record of influencing the design
of experiments and collection of
data in the life and mind sciences.
Over the past four decades,
feminist scientists, historians
and philosophers of science
have presented case study
after case study showing how
sexist bias can distort scientific
results. Examples include
work by Rebecca Jordan-
Young on brain-organization
theory, Anne Fausto-Sterling
on the biological study of sex
differences and Anelis Kaiser on
In the interest of greater
accuracy, controls for sexist bias
need to be more rigorous.
Letitia Meynell Dalhousie
should seek a balance
Conference committees and
symposia chairs should follow
Nature’s lead and be more open
and proactive about gender
balance (Nature 491, 495; 2012).
Publishing an online
declaration of gender-balance
policy would help. Data from each
of the past, say, three meetings
could also be posted online to
indicate the percentage of women
who were registrants, invited
plenary and keynote speakers,
session speakers, programme
committee me mbers, or session
chairs. If there is a significant gap
between the percentage of women
attending the conference and
the overall percentage of women
speakers or committee members,
then a policy overhaul may be
Jennifer L. Martin University of
Queensland, Brisbane, Australia.
Zhu Liu, Fengming Xi Institute
of Applied Ecology, Chinese
Academy of Sciences, Shenyang,
Dabo Guan University of Leeds,
More trials needed to
assess sleeping pills
Sam Fleishman suggests that
the controlled use of sleeping
pills helps to counter the life-
disrupting consequences of
insomnia (Nature 491, 527;
2012). But, to our knowledge,
there is no convincing evidence
that sleep medication can
reactivate the health-restoring
functions of sleep.
Good-quality sleep improves
cognitive performance, vigilance,
memory and mood. Poor sleep
is associated with potentially
damaging physiological effects
such as inflammation (M. R.
Irwin et al. Brain Behav. Immun.
24, 54–57; 2010), compromised
immune-cell activity (E. Fondell
et al. Brain Behav. Immun. 25,
1367–1375; 2011) and telomere
shortening (A. A. Prather et al.
J.Aging Res. 2011, 721390; 2011).
However, the regular use of
sleeping pills has been linked
with increased mortality and
morbidity from infection,
depression or cancer (see, for
example, D. F. Kripke et al. BMJ
Open 2, e000850; 2012).
Large randomizing trials are
needed to evaluate the benefits
and risks of sleeping pills so that
they can be prescribed more
Maximilian Moser Medical
University of Graz, Austria
Daniel F. Kripke University of
California San Diego, California,
The Outlook article ‘Genetics:
Searching for answers’ (Nature
491 (suppl. 7422), S4–S6;
2012) incorrectly stated that
the Simons Simplex Collection
consists of 3,000 blood
samples taken from more than
700 people. In fact, it contains
13,000 blood samples taken
from 3,000 people.
Missing data mean
holes in tree of life
As part of the Open Tree of Life
org), we surveyed publications
covering all domains of life and
found that most phylogenetic
trees and nucleotide alignments
from the past two decades have
been irrevocably lost.
Of 6,193 papers we surveyed
in more than 100 peer-reviewed
journals, only 17% present
accessible trees and alignments
(used to infer relatedness).
Contacting lead authors to
procure data sets was only 19%
successful. DNA sequences
were deposited in GenBank for
almost all these studies, but it is
the actual character alignments
that are pivotal for reproducing
phylogenetic analyses. We
estimate that more than 64% of
existing alignments or trees are
This problem will increasingly
hinder phylogenetic inference
as the use of whole-genome data
sets becomes common. Journals
need to reinforce a policy of
online data deposition, either
as supplementary material or in
repositories such as TreeBASE
Dryad (http://datadryad.org) —
including for data sets based on
previously published sequences.
Ecologists, evolutionary biologists
and others will then have access to
rigorous phylogenetics for testing
Bryan T. Drew* University of
Florida, Gainesville, USA.
*On behalf of 8 co-signatories (see
go.nature.com/gzqcr9 for full list).
Toe-clipping vital to
Keeping a record of the global
decline of amphibian populations
depends on the identification
and marking of individuals in the
field, commonly by toe-clipping.
This work is under threat: the
Brazilian federal government and
want to prohibit toe-clipping
without scientific justification.
Toe-clipping is a simple,
invasive marking technique that
has been in use for decades in
herpetological research. The
Brazilian federal agency that
enforces environmental policies,
IBAMA, is claiming that the
practice is a form of mutilation
and should be a criminal offence
under federal law (see go.nature.
com/qkij7l; in Portuguese).
The Brazilian Herpetological
Society has protested against
this anthropocentric position
in Portuguese) on the grounds
that it would set back efforts to
understand amphibian decline.
Brazil is home to the greatest
amphibian diversity on Earth,
but knowledge of population
dynamics is scant and will
remain so without access to
reliable marking methods. We
acknowledge that toe-clipping is
not an ideal solution but, when
properly implemented, it has
minimal effects on amphibian
survival and behaviour. Without
this technique, it will be harder to
obtain crucial information that
could prevent amphibian species
from becoming extinct (W. C.
Funk et al. Nature 433, 193; 2005).
Décio T. Corrêa* State
University of Campinas, São
Nova Scotia, Canada.
*On behalf of 5 co-signatories (see
go.nature.com/5sgsqo for full list).
17 JANUARY 2013 | VOL 493 | NATURE | 305
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