Vol 452|24 April 2008 NEWS Data show extent of sexism in physics

Women are poorly represented in physics, mak- Switzerland. “Being able to give address the problem in its own ing up just 10% of faculty in the United States, talks is a way of rewarding indi- speakers’ committee. for example, but the reasons for this have proved viduals for their work.” After Towers complained, M. JONES contentious. Now a particle physicist claims to Most particle detectors have Fermilab launched an inter- have hard data showing institutional sexism internal committees that allo- nal review in autumn 2006, at an experiment at one of America’s highest- cate conference presentations says Bruce Chrisman, the profile physics labs. to researchers. These commit- lab’s chief operating officer. Sherry Towers claims that female postdocs tees are frequently male-domi- An edited copy of the review worked significantly harder than their male nated, and Towers believes this obtained by Nature found that peers but were awarded one-third as many con- lies behind the discrimination. the collaboration “followed ference presentations proportionally. “There “I don’t think for a second that its policies correctly”. But the was this shocking difference,” says Towers, who there is a conscious bias going investigator, a senior female now studies statistics at Purdue University in on,” she says. But the commit- Sherry Towers assessed work data physicist, added that com- West Lafayette, Indiana. “Particle physics really tees “are in danger of being for an experiment at Fermilab. plaints of gender discrimina- hasn’t moved forward in 30 years.” prone to patronage and crony- tion in the group “should not Towers used data from publicly available work ism”. Male committee members are more likely be summarily dismissed”. There was a general records to chart the careers of 57 postdoctoral to nominate male protégés to receive presenta- feeling that females were being “passed over” researchers, including nine women, who worked tion time, she claims. for leadership roles, the report says. on the ‘DZero’ particle detector at Fermilab in Some are sceptical of the findings. “I wasn’t DZero’s leaders counter that bias, if it ever Batavia, Illinois, between 1998 and 2006. Tow- convinced that the effect she has found is real,” existed, is not plaguing the current collabora- ers herself worked as a postdoc on the project says Kevin Pitts, a particle physicist at the Uni- tion. A survey of data between August 2006 and between 2000 and 2005. The findings of her versity of Illinois at Urbana-Champaign. Inter- 2007 showed that women gave 17% of all talks survey were striking, she says. She claims that nal papers are not necessarily a direct measure despite making up just 12% of the collaboration, women did 40% more maintenance work of productivity, he argues, and the small number says DZero spokesman Dmitri Denisov. than their male counterparts, and that female of physicists surveyed is not enough to prove Powers says the investigation didn’t focus postdocs produced significantly more ‘internal systematic bias. But Pitts is quick to add that he on postdocs and hasn’t led to real changes at papers’ per year. But based on that productivity has little doubt that females do suffer gender dis- DZero. She wants the conference allocation sys- they were only one-third as likely to be allocated crimination: “In fact,” he says, “I have personally tem to be made more transparent and balanced. conference talks as their male peers, she claims observed this on more than one occasion.” “The changes that need to be made are simple,” (http://arxiv.org/abs/0804.2026). Female physicists contacted by Nature said she says. “It wouldn’t cost them a dime.” Conference presentations are critical to a Towers’s data matched their personal experiences And Towers says gender discrimination ulti- young particle physicist’s career. Papers from of institutional sexism in physics. “You often see a mately forced her out of particle physics. She collaborations such as DZero have hundreds young guy with an older guy gossiping and having adds that in 2004 her former employer, a promi- of authors in alphabetical order. Being given coffee, but never a woman,” says Freya Blekman, a nent northeastern public university, tried to ter- the chance to present results at a meeting is a physicist on the CMS experiment at CERN. “I’m minate her contract after she complained that major way for young researchers to stand out. convinced,” agrees Gagnon. “There is absolutely she wasn’t given adequate maternity leave. She “It’s important,” says Pauline Gagnon, a physicist no shadow of a doubt in my mind.” She says the has since filed a lawsuit against the university. ■ with the ATLAS detector at CERN near Geneva, ATLAS collaboration is thinking about how to Geoff Brumfiel Italian group claims to see dark matter — again

Physicists in Italy claimed last week to have seen something: “They’re seeing a signal, there’s no rarely — if at all — with regular matter such as particles of dark matter. Their announcement has doubt about that,” says Tim Sumner of Imperial atoms. To date, most believe that dark matter got their rivals riled and raises questions about College London. But despite this, critics say has been spotted only indirectly via its pull on what constitutes evidence of a new particle. that they don’t believe the detector has found rotating galaxies and its effect on the shape of Rita Bernabei of the National Institute of the elusive particles. “For me, it’s not proof that the early cosmos. Nuclear Physics in Rome presented her team’s they have seen dark matter,” says Gilles Gerbier, It’s not the first time that Bernabei’s team has latest results on 16 April at an international a physicist at the Centre for Atomic Energy in made this claim. In 2000, they also claimed to meeting of particle physicists in Venice, Italy. Saclay, France. He adds that he’s stumped by have directly observed dark matter. The team uses Their detector, DAMA/LIBRA (Dark Matter Large what’s causing the signal. ultrapure sodium iodide crystals, which theory Sodium Iodide Bulk for Rare Processes), located Dark matter is believed by most physicists and predicts will give off flashes of light when they deep under the country’s Gran Sasso mountain, astronomers to make up some 85% of the matter are struck by dark-matter particles. After several seems to be observing dark matter, Bernabei says. in the Universe. Most theories predict that it is years of collecting data in the late 1990s, the Most agree that the experiment is picking up some form of massive particle that interacts very group saw an increase in the number of flashes

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GUT REACTIONS Analytical technique shows how metabolism varies between populations. www.nature.com/news ANATOMICAL TRAVELOGUE/SPL ANATOMICAL Swiss ‘dignity’ law is threat to plant biology When it comes to the ethics of experimenting on living subjects, plant biologists have had cause for a certain smugness. But perhaps no longer in Switzerland. The Swiss federal government’s ethics committee on non-human biotechnology has mapped out guidelines to help granting agencies decide which research applications deeply offend the dignity of plants — and hence become unfundable. Although most people might be bewildered that a discussion on how to define ‘plant dignity’ should be taking place at all, the stakes for Swiss plant scientists RICHARDSON/CORBIS J. are high. The Gene Technology Law, which Living creatures trapped in undignified conditions? A tricky ethical question for Swiss plant biologists. came into effect in 2004, stipulates that ‘the dignity of creatures’ should be considered The government called on the advice of technologies, for example in roses, which in any research. The phrase has been widely its ethics committee two years ago to help require male sterility, and the commercial criticized for its general woolliness, but it develop a definition for plants. “My first development of seedless fruits. indisputably includes plants. reaction was — what the heck are we doing Keller sees the issue as providing another All plant biotechnology grant considering the dignity of plants,” says tool for opponents to argue against any form applications must now include a paragraph Schefer. “But this very broad provision exists, of plant biotechnology, which is already explaining the extent to which plant dignity and we have to help to prevent a legal mire.” very difficult to conduct in Switzerland. is considered. “But scientists don’t know The committee has created a decision Schefer says that things will start to become what it means,” says Beat Keller of the tree presenting the different issues that clearer when legal challenges to specific Institute of Plant Biology at the University need to be taken into account for each research projects come to court, and case of Zurich who is running the first field trial case. But it has come up with few concrete law becomes established. — of disease-resistant corn (maize) — to be examples of what type of experiment might The definition of what constitutes dignity approved under the new legislation. be considered an unacceptable insult to in animals is currently being tested in a “At the moment not even authorities who plant dignity. The committee does not Zurich court. Primate-research projects decide on grants know what the ‘dignity of consider that genetic engineering of plants at the ETH Zurich technology institute, plants’ really means,” says Markus Schefer, automatically falls into this category, but which involve separating young marmosets a constitution lawyer at the University of its majority view holds that it would if from their mothers, have been put on hold Basel and a member of the ethics committee. the genetic modification caused plants to while the court decides if they conflict with “That’s why we were asked to deliberate.” ‘lose their independence’ — for example the animals’ dignity. A ruling is expected The constitution says that the ‘dignity of by interfering with their capacity to this year. Whichever way it falls, the creatures’ must be taken into account in the reproduce. The statement has confused decision is likely to end up in the federal gene-technology arena, which is why the plant geneticists, who point out the contrast constitutional court. ■ term has been adopted into the regulations. with traditional plant-hybridization Alison Abbott

every June and a decrease during December. The But once again, DAMA/LIBRA’s rivals are experiment with the years of data needed to see seasonal oscillation, they claimed, was due to coming up empty-handed. Sadoulet’s own the annual fluctuation in dark-matter particles. Earth’s annual motion with and against a stream of Cryogenic Dark Matter Search II detector And the fluctuation matches “all the several dark matter swirling around the Milky Way. announced a null result earlier this year (see requirements of dark matter”, she says, adding But rival groups failed to see the signal and Nature 452, 6–7; 2008). And other second- and that two papers have just been posted on the heaped criticism on the group. They demanded third-generation experiments are similarly failing popular preprint server ArXiv, which provide the proof that the Italians’ detection was not caused to see a signal. If the signal DARMA gets is dark details of her work. by systematic errors such as natural radiation or matter, Sadoulet says, “it’s certainly not the dark But unless another team sees something, glitches in their electronics. matter we were looking for”. He also continues Gerbier says, it’s unlikely that the wider physics This time around, the DAMA/LIBRA team to criticize the group for failing to share enough community will accept the Italian claim. “There seems to have addressed some of those details of its data. “There has not been enough should be different ways of seeing the same concerns, according to Bernard Sadoulet, an information provided to the community,” he says. thing,” he says. “A single experiment cannot astrophysicist at the University of California, Bernabei defends her group’s finding. Most discover dark matter.” Berkeley. For example, their new detector uses other detectors try to measure direct collisions Bernabei agrees. Proving her team’s findings larger, less strongly radioactive crystals, and between a dark-matter particle and an atomic will take “time and patience”, she says. ■ they have proven the stability of their detectors. nucleus, she says. DAMA/LIBRA is the only Geoff Brumfiel

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