Sloppy Science Happens More Than You Think
The media loves to tout scientific breakthroughs, and few are as toutable – and in turn, have been as touted – as CRISPR. This method of targeted DNA excision was discovered in bacteria, which use it as an adaptive immune system to combat reinfection with a previously encountered virus.
Shouldn't the editors at a Nature journal know better than to have published an incorrect paper in the first place?
It is cool on so many levels: not only is the basic function fascinating, reminding us that we still have more to discover about even simple organisms that we thought we knew so well, but the ability it grants us to remove and replace any DNA of interest has almost limitless applications in both the lab and the clinic. As if that didn't make it sexy enough, add in a bicoastal, male-female, very public and relatively ugly patent battle, and the CRISPR story is irresistible.
And then last summer, a bombshell dropped. The prestigious journal Nature Methods published a paper in which the authors claimed that CRISPR could cause many unintended mutations, rendering it unfit for clinical use. Havoc duly ensued; stocks in CRISPR-based companies plummeted. Thankfully, the authors of the offending paper were responsible, good scientists; they reassessed, then recanted. Their attention- and headline- grabbing results were wrong, and they admitted as much, leading Nature Methods to formally retract the paper this spring.
How did this happen? Shouldn't the editors at a Nature journal know better than to have published this in the first place?
Alas, high-profile scientific journals publish misleading and downright false results fairly regularly. Some errors are unavoidable – that's how the scientific method works. Hypotheses and conclusions will invariably be overturned as new data becomes available and new technologies are developed that allow for deeper and deeper studies. That's supposed to happen. But that's not what we're talking about here. Nor are we talking about obvious offenses like outright plagiarism. We're talking about mistakes that are avoidable, and that still have serious ramifications.
The cultures of both industry and academia promote research that is poorly designed and even more poorly analyzed.
Two parties are responsible for a scientific publication, and thus two parties bear the blame when things go awry: the scientists who perform and submit the work, and the journals who publish it. Unfortunately, both are incentivized for speedy and flashy publications, and not necessarily for correct publications. It is hardly a surprise, then, that we end up with papers that are speedy and flashy – and not necessarily correct.
"Scientists don't lie and submit falsified data," said Andy Koff, a professor of Molecular Biology at Sloan Kettering Institute, the basic research arm of Memorial Sloan Kettering Cancer Center. Richard Harris, who wrote the book on scientific misconduct running the gamut from unconscious bias and ignorance to more malicious fraudulence, largely concurs (full disclosure: I reviewed the book here). "Scientists want to do good science and want to be recognized as such," he said. But even so, the cultures of both industry and academia promote research that is poorly designed and even more poorly analyzed. In Rigor Mortis: How Sloppy Science Creates Worthless Cures, Crushes Hope, and Wastes Millions, Harris describes how scientists must constantly publish in order to maintain their reputations and positions, to get grants and tenure and students. "They are disincentivized from doing that last extra experiment to prove their results," he said; it could prove too risky if it could cost them a publication.
Ivan Oransky and Adam Marcus founded Retraction Watch, a blog that tracks the retraction of scientific papers, in 2010. Oransky pointed out that blinded peer review – the pride and joy of the scientific publishing enterprise – is a large part of the problem. "Pre-publication peer review is still important, but we can't treat it like the only check on the system. Papers are being reviewed by non-experts, and reviewers are asked to review papers only tangentially related to their field. Moreover, most peer reviewers don't look at the underlying or raw data, even when it is available. How then can they tell if the analysis is flawed or the data is accurate?" he wondered.
Mistaken publications also erode the public's opinion of legitimate science, which is problematic since that opinion isn't especially high to begin with.
Koff agreed that anonymous peer review is valuable, but severely flawed. "Blinded review forces a collective view of importance," he said. "If an article disagrees with the reviewer's worldview, the article gets rejected or forced to adhere to that worldview – even if that means pushing the data someplace it shouldn't necessarily go." We have lost the scientific principle behind review, he thinks, which was to critically analyze a paper. But instead of challenging fundamental assumptions within a paper, reviewers now tend to just ask for more and more supplementary data. And don't get him started on editors. "Editors are supposed to arbitrate between reviewers and writers and they have completely abdicated this responsibility, at every journal. They do not judge, and that's a real failing."
Harris laments the wasted time, effort, and resources that result when erroneous ideas take hold in a field, not to mention lives lost when drug discovery is predicated on basic science findings that end up being wrong. "When no one takes the time, care, and money to reproduce things, science isn't stopping – but it is slowing down," he noted. Mistaken publications also erode the public's opinion of legitimate science, which is problematic since that opinion isn't especially high to begin with.
Scientists and publishers don't only cause the problem, though – they may also provide the solution. Both camps are increasingly recognizing and dealing with the crisis. The self-proclaimed "data thugs" Nick Brown and James Heathers use pretty basic arithmetic to reveal statistical errors in papers. The microbiologist Elisabeth Bik scans the scientific literature for problematic images "in her free time." The psychologist Brian Nosek founded the Center for Open Science, a non-profit organization dedicated to promoting openness, integrity, and reproducibility in scientific research. The Nature family of journals – yes, the one responsible for the latest CRISPR fiasco – has its authors complete a checklist to combat irreproducibility, à la Atul Gawande. And Nature Communications, among other journals, uses transparent peer review, in which authors can opt to have the reviews of their manuscript published anonymously alongside the completed paper. This practice "shows people how the paper evolved," said Koff "and keeps the reviewer and editor accountable. Did the reviewer identify the major problems with the paper? Because there are always major problems with a paper."
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on scientific creativity and progress to give you a therapeutic dose of inspiration headed into the weekend.
Here are the promising studies covered in this week's Friday Five:
- Kids stressing you out? They could be protecting your health.
- A new device unlocks the heart's secrets
- Super-ager gene transplants
- Surgeons could 3D print your organs before operations
- A skull cap looks into the brain like an fMRI
This article originally appeared in One Health/One Planet, a single-issue magazine that explores how climate change and other environmental shifts are making us more vulnerable to infectious diseases by land and by sea - and how scientists are working on solutions.
On a warm summer day, forests, meadows, and riverbanks should be abuzz with insects—from butterflies to beetles and bees. But bugs aren’t as abundant as they used to be, and that’s not a plus for people and the planet, scientists say. The declining numbers of insects, coupled with climate change, can have devastating effects for people in more ways than one. “Insects have been around for a very long time and can live well without humans, but humans cannot live without insects and the many services they provide to us,” says Philipp Lehmann, a researcher in the Department of Zoology at Stockholm University in Sweden. Their decline is not just bad, Lehmann adds. “It’s devastating news for humans.
”Insects and other invertebrates are the most diverse organisms on the planet. They fill most niches in terrestrial and aquatic environments and drive ecosystem functions. Many insects are also economically vital because they pollinate crops that humans depend on for food, including cereals, vegetables, fruits, and nuts. A paper published in PNAS notes that insects alone are worth more than $70 billion a year to the U.S. economy. In places where pollinators like honeybees are in decline, farmers now buy them from rearing facilities at steep prices rather than relying on “Mother Nature.”
And because many insects serve as food for other species—bats, birds and freshwater fish—they’re an integral part of the ecosystem’s food chain. “If you like to eat good food, you should thank an insect,” says Scott Hoffman Black, an ecologist and executive director of the Xerces Society for Invertebrate Conservation in Portland, Oregon. “And if you like birds in your trees and fish in your streams, you should be concerned with insect conservation.”
Deforestation, urbanization, and agricultural spread have eaten away at large swaths of insect habitat. The increasingly poorly controlled use of insecticides, which harms unintended species, and the proliferation of invasive insect species that disrupt native ecosystems compound the problem.
“There is not a single reason why insects are in decline,” says Jessica L. Ware, associate curator in the Division of Invertebrate Zoology at the American Museum of Natural History in New York, and president of the Entomological Society of America. “There are over one million described insect species, occupying different niches and responding to environmental stressors in different ways.”
Jessica Ware, an entomologist at the American Museum of Natural History, is using DNA methods to monitor insects.
In addition to habitat loss fueling the decline in insect populations, the other “major drivers” Ware identified are invasive species, climate change, pollution, and fluctuating levels of nitrogen, which play a major role in the lifecycle of plants, some of which serve as insect habitants and others as their food. “The causes of world insect population declines are, unfortunately, very easy to link to human activities,” Lehmann says.
Climate change will undoubtedly make the problem worse. “As temperatures start to rise, it can essentially make it too hot for some insects to survive,” says Emily McDermott, an assistant professor in the Department of Entomology and Plant Pathology at the University of Arkansas. “Conversely in other areas, it could potentially also allow other insects to expand their ranges.”
Without Pollinators Humans Will Starve
We may not think much of our planet’s getting warmer by only one degree Celsius, but it can spell catastrophe for many insects, plants, and animals, because it’s often accompanied by less rainfall. “Changes in precipitation patterns will have cascading consequences across the tree of life,” says David Wagner, a professor of ecology and evolutionary biology at the University of Connecticut. Insects, in particular, are “very vulnerable” because “they’re small and susceptible to drying.”
For instance, droughts have put the monarch butterfly at risk of being unable to find nectar to “recharge its engine” as it migrates from Canada and New England to Mexico for winter, where it enters a hibernation state until it journeys back in the spring. “The monarch is an iconic and a much-loved insect,” whose migration “is imperiled by climate change,” Wagner says.
Warming and drying trends in the Western United States are perhaps having an even more severe impact on insects than in the eastern region. As a result, “we are seeing fewer individual butterflies per year,” says Matt Forister, a professor of insect ecology at the University of Nevada, Reno.
There are hundreds of butterfly species in the United States and thousands in the world. They are pollinators and can serve as good indicators of other species’ health. “Although butterflies are only one group among many important pollinators, in general we assume that what’s bad for butterflies is probably bad for other insects,” says Forister, whose research focuses on butterflies. Climate change and habitat destruction are wreaking havoc on butterflies as well as plants, leading to a further indirect effect on caterpillars and butterflies.
Different insect species have different levels of sensitivity to environmental changes. For example, one-half of the bumblebee species in the United States are showing declines, whereas the other half are not, says Christina Grozinger, a professor of entomology at the Pennsylvania State University. Some species of bumble bees are even increasing in their range, seemingly resilient to environmental changes. But other pollinators are dwindling to the point that farmers have to buy from the rearing facilities, which is the case for the California almond industry. “This is a massive cost to the farmer, which could be provided for free, in case the local habitats supported these pollinators,” Lehmann says.
For bees and other insects, climate change can harm the plants they depend on for survival or have a negative impact on the insects directly. Overly rainy and hot conditions may limit flowering in plants or reduce the ability of a pollinator to forage and feed, which then decreases their reproductive success, resulting in dwindling populations, Grozinger explains.
“Nutritional deprivation can also make pollinators more sensitive to viruses and parasites and therefore cause disease spread,” she says. “There are many ways that climate change can reduce our pollinator populations and make it more difficult to grow the many fruit, vegetable and nut crops that depend on pollinators.”
Disease-Causing Insects Can Bring More Outbreaks
While some much-needed insects are declining, certain disease-causing species may be spreading and proliferating, which is another reason for human concern. Many mosquito types spread malaria, Zika virus, West Nile virus, and a brain infection called equine encephalitis, along with other diseases as well as heartworms in dogs, says Michael Sabourin, president of the Vermont Entomological Society. An animal health specialist for the state, Sabourin conducts vector surveys that identify ticks and mosquitoes.
Scientists refer to disease-carrying insects as vector species and, while there’s a limited number of them, many of these infections can be deadly. Fleas were a well-known vector for the bubonic plague, while kissing bugs are a vector for Chagas disease, a potentially life-threatening parasitic illness in humans, dogs, and other mammals, Sabourin says.
As the planet heats up, some of the creepy crawlers are able to survive milder winters or move up north. Warmer temperatures and a shorter snow season have spawned an increasing abundance of ticks in Maine, including the blacklegged tick (Ixodes scapularis), known to transmit Lyme disease, says Sean Birkel, an assistant professor in the Climate Change Institute and Cooperative Extension at the University of Maine.
Coupled with more frequent and heavier precipitation, rising temperatures bring a longer warm season that can also lead to a longer period of mosquito activity. “While other factors may be at play, climate change affects important underlying conditions that can, in turn, facilitate the spread of vector-borne disease,” Birkel says.
For example, if mosquitoes are finding fewer of their preferred food sources, they may bite humans more. Both male and female mosquitoes feed on sugar as part of their normal behavior, but if they aren’t eating their fill, they may become more bloodthirsty. One recent paper found that sugar-deprived Anopheles gambiae females go for larger blood meals to stay in good health and lay eggs. “More blood meals equals more chances to pick up and transmit a pathogen,” McDermott says, He adds that climate change could reduce the number of available plants to feed on. And while most mosquitoes are “generalist sugar-feeders” meaning that they will likely find alternatives, losing their favorite plants can make them hungrier for blood
Similar to the effect of losing plants, mosquitoes may get turned onto people if they lose their favorite animal species. For example, some studies found that Culex pipiens mosquitoes that transmit the West Nile virus feed primarily on birds in summer. But that changes in the fall, at least in some places. Because there are fewer birds around, C. pipiens switch to mammals, including humans. And if some disease-carrying insect species proliferate or increase their ranges, that increases chances for human infection, says McDermott. “A larger concern is that climate change could increase vector population sizes, making it more likely that people or animals would be bitten by an infected insect.”
Science Can Help Bring Back the Buzz
To help friendly insects thrive and keep the foes in check, scientists need better ways of trapping, counting, and monitoring insects. It’s not an easy job, but artificial intelligence and molecular methods can help. Ware’s lab uses various environmental DNA methods to monitor freshwater habitats. Molecular technologies hold much promise. The so-called DNA barcodes, in which species are identified using a short string of their genes, can now be used to identify birds, bees, moths and other creatures, and should be used on a larger scale, says Wagner, the University of Connecticut professor. “One day, something akin to Star Trek’s tricorder will soon be on sale down at the local science store.”
Scientists are also deploying artificial intelligence, or AI, to identify insects in agricultural systems and north latitudes where there are fewer bugs, Wagner says. For instance, some automated traps already use the wingbeat frequencies of mosquitoes to distinguish the harmless ones from the disease-carriers. But new technology and software are needed to further expand detection based on vision, sound, and odors.
“Because of their ubiquity, enormity of numbers, and seemingly boundless diversity, we desperately need to develop molecular and AI technologies that will allow us to automate sampling and identification,” says Wagner. “That would accelerate our ability to track insect populations, alert us to the presence of new disease vectors, exotic pest introductions, and unexpected declines.”