The long, squiggly arms of a brittle star—a relative of the sea star with baroque tendencies—have a surprising relationship with the rest of its body.
Its arms function more or less independently, sensing their own environment and making their own decisions about how to react to it. They are only loosely coordinated by a nerve ring in the animal’s core. A single brittle star is almost like five co-joined animals with a mutual interest in where to go, what to eat and making little brittle stars.
And yet now there appears to be something far stranger about the biology of at least one species: the entire body of Ophiocoma wendtii appears capable of forming a blurry but serviceable image, like a squirmy but strangely cute Eye of Sauron.
It gets weirder.
This full-body vision is extinguished at night, when the animal’s sensitivity to light paradoxically increases, and its maroon body turns beige. How and why this animal possesses these strange characteristics were the subjects of a study published in January in Current Biology.
To see, biologists require spatial vision. It isn’t enough to merely detect light; one must form an image. Almost all animals can sense light. Fewer can see.
Traditionally it was pretty apparent who could see and who could not because a creature either had eyes or it didn’t. Recently, however, invertebrate biologists are realizing that eyes may be optional for vision.
In 2018, scientists reported that the spiny sea urchin Diadema africanum is apparently capable of resolving images without eyes—a concept called “extraocular vision.” They did not, however, understand how.
Then a team of European and American scientists led by Lauren Sumner-Rooney at the Oxford University Museum of Natural History began to suspect that, despite a conspicuous lack of eyes, O. wendtii could also see.
They tested this by placing the brittle stars in the center of arenas surrounded by walls with black bars on one side to simulate shelter. More brittle stars ended up at the black bars than would be expected by chance. Dark-adapted beige O.wendtii, however, were not capable of finding these black bars at rates exceeding chance whether they were supplied with fluorescent lights or daylight, seemingly ruling out light intensity or circadian rhythms as an explanation.
This behavioral combination was particularly puzzling because a close relative, O. pumila, has all the same light-detecting equipment, but when placed in the same arenas, these animals end up randomly distributed at any time of day. They are blind.
However, the team knew that the bodies of both brittle stars are studded with light receptors called opsins. O. pumila may not be able to see, but it can sense light; when exposed to light, it hides in sand or crevices right where it is. O.wendtii, on the other hand, skitters to the nearest shelter. The only obvious difference is that O. pumila is not ever red. What difference could being red make to seeing?
In order to be able to form an image, a light receptor needs directionality. If you can’t tell what direction light is coming from, you can’t really infer much about what the world looks like in a particular spot. Consequently, the first requirement for vision after light sensing is some sort of screening mechanism, so that any given receptor knows that the light coming from this particular spot is arriving in this amount.
One method of screening light is (duh) sunscreen. Pigment is natural sunscreen, and O. wendtii is covered in red pigment packets called chromatophores by day. At night, the chromatophores retract. When the scientists scanned both brittle star species and measured the field of view from each animal’s light sensors, they discovered deployed pigment packets narrow the field of vision by physically blocking light. The angular aperture narrows from about 118 degrees to 68 degrees in O. wendtii with chromatophores blazing.
If the light sensors of O. wendtii are directional, that explains how the array widely scattered over their entire body could form an image. Its entire body is indeed an eye. But the image formed might be extremely strange to us. A brittle star is not a ball, like a sea urchin. It is five unruly arms attached to a conciliating core. How does a human even begin to think about what the image formed by such an array might look like?
The scientists attempted to reconstruct an image of a reef inferred by the resolution they measured. In the best-case scenario, a blurry bar of dark gray appears against a lighter gray background. Crude, to be sure, but maybe enough for a motivated brittle star to reach the all-important Minimum Location for Not Getting Eaten.
Since chromatophores block light, that also explains why their general light sensitivity improves at night, which is convenient because vision then may be impossible anyway.
It is intriguing that animals with such a strange system for perceiving their world belong to the major animal group that is the closest kin of vertebrates. Much more distantly related animals—the mighty arthropods (e.g., insects and lobsters) and mollusks (e.g., octopus and squid), most significantly—have eyes. Even some starfish possess proper eyes: compound eyes squeezed into their tube feet, or simple ocelli (the pressure to see well may be stronger for starfish because they are active hunters).
To discover such an alternative vision system in not just one but two such close relatives (sea urchins, like brittle stars, are echinoderms) seems surprising and counterintuitive. On the other hand, that a group of animals with radial symmetry and an apparent nonchalance about getting chopped in two is vertebrates’ closest major relative is also surprising, as has been pointed out many times.
Among vertebrates, many fish, amphibians and reptiles have a third eye, and at least one had a fourth. Flatfish have eyes that migrate around their bodies. Many vertebrates—including mammals—possess light receptors apart from their eyes. If a vertebrate had for some reason adopted radial symmetry, could we have seen equally surprising ways of seeing in our own ranks?
When the immune system fights viruses, timing is key. And this maxim may be especially true for its defense against the deadly severe form of COVID-19.
Several new studies of immune response to SARS-CoV-2, the virus that causes the disease, suggest timing could be critical for a class of proteins known as interferons, which are being researched as potential treatments. These immune proteins suppress viral replication early in disease. Yet if they are active later, some scientists think they can exacerbate the harmful inflammation that forces some COVID-19 patients onto life support. Interferons are “a double-edged sword,” says immunologist Eui-Cheol Shin of the Korea Advanced Institute of Science and Technology.
Researchers have been looking at both of that sword’s edges. About a decade ago, when Shin was studying the viral disease hepatitis C, interferons were used as a standard treatment. But examinations of some conditions suggested they should not be employed. For example, researchers in Paris found that too much of the proteins can lead to a diseases known as children’s interferonopathies. In a sense, each of these two perceptions of interferons is correct. And understanding when, and to what extent, using them is warranted could be a critical factor in treating COVID-19.
The researchers in Paris analyzed blood from 50 people with varying COVID-19 severity and 18 healthy controls. They determined that severely ill patients had lower overall counts of lymphocytes (a type of white blood cell). Using techniques to analyze broad-based gene activity and measure specific proteins, two trends stood out: Compared with patients with milder forms of the disease, people with severe COVID-19 had an exaggerated inflammatory response, coupled with a marked decrease in interferons. And among severe COVID-19 patients, the interferon deficiency was worse in those who died versus those who stabilized, the team reported on July 13 in Science.
“We were surprised,” says Benjamin Terrier, a clinician-researcher at Cochin Hospital in Paris, who was co-senior author of the study. “It was not our hypothesis.” An analysis published in the May 28 issue of Cell by researchers at the Icahn School of Medicine at Mount Sinai turned up a similar dual signature: low interferon levels and elevated inflammatory proteins.
Meanwhile, in another new study, Shin and his colleagues used single-cell RNA sequencing to analyze gene activity in immune cells. They analyzed blood samples from eight patients with mild or severe COVID-19, four healthy donors and five people with severe influenza—more than 59,000 cells in total. The researchers employed computer algorithms to compare individual cells’ RNA, and they expected patterns to cluster by cell type. That is, they anticipated that T cells, lymphocytes that coordinate an immune response or kill invading pathogens, would look a lot alike, whether they were taken from patients with COVID-19 or influenza. But that was not the case. Instead the cellular profiles grouped by disease. For example, T cells from COVID-19 patients did not resemble those from people with influenza. Rather they looked more like COVID-19 B cells, Shin says.
This curious observation prompted his team to search for molecules that might serve as a common mediator influencing various immune cells. Comparing gene activity profiles, the researchers first noticed a flu-COVID dichotomy: influenza cells showed higher activity in genes regulated by interferons, whereas inflammatory genes driven by so-called tumor necrosis factor (TNF) and interleukin-1 beta (IL-1β) predominated in COVID-19. They then compared severe versus mild COVID-19 samples and focused on a specific pool of immune cells called monocytes. In severe COVID-19 patients, these first-defender cells had increased activity in interferon-stimulated genes in addition to the TNF/IL-1β inflammatory genes. But mild COVID-19 monocytes only had the TNF/IL-1β signature, Shin and his colleagues reported on July 10 in Science Immunology.
At first glance, the recent French and South Korean papers seemed to reach contradictory conclusions—with severely ill COVID-19 patients showing weaker interferon responses in Terrier and his colleagues’ analysis and more interferon activity in Shin and his colleagues’ study. The difference could come down to technique and timing. The French researchers analyzed RNA in samples containing mixtures of immune cells, whereas the South Korean team sequenced RNA in individual cells and observed interferon differences in monocytes. But because monocytes make up just a tenth of total make up less than a tenth of white blood cells, an increased signal in this population could be obscured by other cells in the French team’s bulk samples, Shin suggests.
There is another side to the coin, however. Multiple immune cells produce interferons and are presumably influenced by the proteins. Yet the Korean team’s single-cell profiling only looked at interferons’ effect on monocytes. “What is the impact of a change in one small cell population on the whole system? It’s really complicated to interpret,” Terrier says.
“The interferon response is a little bit tricky,” says Rudragouda Channappanavar, a viral immunologist at the University of Tennessee Health Science Center, who was not involved with the new studies. The response protects the body from infections by thwarting viral replication. “The body needs it, without a doubt,” he says. “But viruses are smart. They have several proteins that can antagonize and suppress early interferon responses.” One of SARS-CoV-2’s own defenders, a viral protein called Nsp1, can shut down the host cell’s production of immune molecules, including interferons, researchers in Munich reported on July 17 in Science.
In earlier studies with Stanley Perlman of the University of Iowa, Channappanavar analyzed mouse models for the coronaviruses that cause severe acute respiratory syndrome (SARS) and Middle East respiratory syndrome (MERS). Those studies showed that “if the interferon response begins before viral replication peaks, we will have protective immunity,” he says. If the viruses thwart this antiviral defense, however, the delayed interferon response becomes pathogenic—summoning too many monocytes, which secrete inflammatory molecules and cause tissue damage. “It’s the relative timing of interferon with virus replication that’s the key,” Channappanavar says.
Therapeutically, the findings suggest that interferons matter in the initial phase of infection. “If you give interferon early, you can really increase the antiviral response. This is where you gain the most,” says Miriam Merad, who directs the Precision Immunology Institute at the Icahn School of Medicine at Mount Sinai and was not involved with the new research. If a person with COVID-19 has already progressed to having inflammation, “and you go in and give interferon, you are going to make things worse,” she says. In an open-label preprint study in China, interferon nasal drops prevented the disease in at-risk medical staff who had treated infected individuals. Early unpublished data from COVID-19 patients hospitalized in the U.K. suggest that interferons inhaled directly into the lungs shortened hospital stays and increased odds of recovery. And a randomized trial in Iran is testing whether the proteins can enhance a base therapeutic regimen in moderate to severe COVID-19 patients.
Read more about the coronavirus outbreak from Scientific American here. And read coverage from our international network of magazines here.
The U.S. has been roiled this year by two crises that seem on the surface to be unrelated: the coronavirus pandemic and law-enforcement killings of black Americans—the latter leading to mass protests and police violence toward protesters. Although the immediate causes of these two tragedies seem distinct, both have their roots in structural racism. The virus has killed a disproportionate number of black people (as well as other people of color), and black people are by some estimates 2.5 times more likely than white people to be killed by the police. Support is building for police reform, and we can take concrete steps immediately to protect the health of black Americans.
Deep health inequities have always existed in the U.S., but the pandemic has shone an especially harsh light on them. A report from the Centers for Disease Control and Prevention on a sample of 580 people hospitalized with confirmed cases of COVID-19 found that 33 percent of patients were black in a population sample where just 18 percent of the people were black. White people made up 59 percent of the same population, but only 45 percent were infected. Through April 16 in New York City, the death rate among blacks was 92 per 100,000 people and among Latinx people 74 per 100,000—whereas the numbers for white people and Asian people were 45 and 35 per 100,000, respectively. These trends are not limited to New York: the coronavirus has infected and killed an outsize number of black people across the U.S.
Many people of color work in so-called essential industries such as nursing or home health care, grocery stores and mass transit, where they are more likely to come into close contact with people who are sick. To make matters worse, these jobs are often poorly paid, and a large proportion of such workers lack health or life insurance. In addition, many black, Latinx and indigenous communities have high rates of underlying health conditions, including diabetes, hypertension and heart disease, which are known risk factors for severe illness and death from COVID-19. These disparities can be traced back largely to the racism and redlining that have resulted in poor, overcrowded housing and exposed people of color to more severe levels of air pollution—factors that exacerbate all these health problems. The Families First Coronavirus Response Act and the Coronavirus Aid, Relief, and Economic Security (CARES) Act, both of which Congress passed in March, did very little to protect the health of essential workers, according to policy experts across the political spectrum, because they focused more on providing economic relief than medical care or benefits.
Tackling these health inequalities fully will require major reforms in our health insurance system and a true effort to address deep-seated racial and economic injustices. Some possible short-term solutions are out there: the nonpartisan Brookings Institution published a report in March that called for enrolling all uninsured frontline essential workers and their families in a new “Medicare COVID” program that would cover all testing, treatment and vaccinations related to COVID-19. (The CARES Act mandates that insurance providers cover COVID-19 testing but not treatment.)
A proposal from the progressive advocacy group Center for American Progress (CAP) asks for hazard pay for essential workers and paid medical or family leave for workers to care for themselves or a sick family member (the Families First legislation included a provision for two weeks’ paid sick leave but was full of exemptions, mostly for large businesses and health care providers). CAP also called for Congress to ensure coverage for COVID-19 testing and treatments, regardless of immigration status. The House recently passed a $3-trillion bill that would include many of these provisions, but the legislation appears doomed in the Senate.
We should adopt these measures as a stopgap. But in the long term, we need to expand access to affordable health care for all Americans, and it should not be tied to employment. The Affordable Care Act (ACA) has made great strides toward this end and has proved popular with most Americans, despite Republican efforts to dismantle it. At minimum, we need to reopen ACA enrollment in every state and provide incentives for all states to expand Medicaid, which insures about 75 million low-income Americans.
Too many people of color lack access to even the most basic health care, and others risk losing coverage for themselves and their families if they lose their jobs. The next time there is a pandemic—and there will be a next time—we cannot allow the same appalling racial disparities to determine who lives and who dies.
Read more about the coronavirus outbreak from Scientific American here. And read coverage from our international network of magazines here.
The SUV-sized Perseverance rover due to launch to Mars this week has a sidekick: a svelte four-pound helicopter with four-foot-long rotor blades that weigh as light as feathers. It will attempt to make the first powered flight on another planet, a potential game-changer for deep-space exploration.
If all goes as planned, dispatching the helicopter from Perseverance’s belly will be an early first step for the Mars 2020 mission after the rover’s parachute, retro-rocket and sky crane descend onto the flat floor of the planet’s Jezero Crater in early 2021. Intended solely as a technology demonstration, the rotorcraft, named Ingenuity, will attempt up to five powered flights in the thin Martian air, which is less than 1 percent the density of Earth’s atmosphere.
These trips will be quick, each lasting about 90 seconds from takeoff to landing, which is all the time available before Ingenuity’s batteries drain. To push enough air downward to create upward lift, its blades have to spin at about 2,800 revolutions per minute—10 times faster than helicopters on Earth—so each flight will consume about 350 watts of power. Ingenuity’s solar-powered batteries will take a full Martian day (a little longer than an Earth day) to recharge between flights. The craft’s peak altitude will be only about 16 feet, but the conditions it will face will be comparable to those experienced at 100,000 feet on Earth—more than twice as high as any helicopter has flown.
Planning for the Mars helicopter began more than six years ago at NASA’s Jet Propulsion Laboratory’s (JPL’s) autonomous systems division, which studies next-generation capabilities for space exploration. The team, headed by engineer MiMi Aung, was challenged to create a flying vehicle that would work on the Red Planet.
If successful, an aircraft could carry scientific instruments to places where rovers and landers cannot go, such as exposed ice scarps on the sides of cliffs or inside the walls of steep craters. The aircraft could loft cameras to scout locations for future rovers—and, one day, astronauts—to explore. Doing so would provide far more detailed pictures than what is available via current orbital imagery, which can resolve features on Mars down to about three feet or so. “Imagine having centimeter-level-precision, [or about half-inch-precision], images of possible destinations and characterizing those,” Aung says.
Future concepts include swarms of craft that fly together and work cooperatively or a larger flight vehicle that could independently travel from location to location, enabling a new type of otherworldly exploration. JPL is studying potential Mars helicopters weighing up to to 33 pounds that could carry a payload up to about 3.3 pounds. NASA also is funding a far more ambitious helicopter-based mission called Dragonfly to explore the rich organic chemistry on Saturn’s largest moon Titan. The natural satellite has a thick atmosphere and lakes and seas of liquid methane beneath its thick hydrocarbon atmosphere, as well as a watery underground ocean, making it a tantalizing world in the search for life beyond Earth.
“What’s really changed in the last several years is the drone revolution—just how much development there has been in drone and autonomous flight technology,” says planetary scientist Elizabeth Turtle, Dragonfly’s principal investigator at the Johns Hopkins University Applied Physics Laboratory. “When we were looking at mission architectures that made sense to propose to explore Titan, we realized that we really now had all of this capability.”
First, though, powered flight on Mars must be proved possible. And doing so is the sole goal of the $85-million Ingenuity mission.
The helicopter is a bit bigger than a softball, minus its four carbon-fiber blades, which spin on two counterrotating rotors and sits on four legs, each 15 inches long. It carries diminutive avionics and communications equipment, a navigation camera, a single solar panel and rechargeable lithium-ion batteries—as well as heaters to keep the electronics warm through the frigid Martian nights. There are no science instruments onboard; just a high-resolution color imager.
Designing the helicopter required innovation across every domain of aerospace engineering—thermal, mechanical, structural, power, materials, and so on. “We had to remove all the boundaries,” Aung says. “We’re used to having our own chassis … and our own computer for each subsystem. Integrating all of that together, and then combining, also, the aero aspect of it, pulling the whole system together in such a light weight…, was the first challenge. That’s what also made it really fun and interesting.”
Ingenuity will ride to Mars attached to the Perseverance rover and behind a shield to protect it from debris that may be kicked up during the sky crane’s descent to the planet’s surface. The launch is scheduled for 7:50–9:50 A.M. EDT on July 30 at Cape Canaveral Air Force Station in Florida. Perseverance is expected to land on Mars on February 18, 2021.
As the rover begins beaming back data that will allow scientists to assess Jezero Crater, the landing site for NASA’s fifth and most ambitious Mars rover, Aung and her team will scout for a flat 33-by-33-foot site to become the experimental airfield for Ingenuity’s test flights, which are scheduled to begin in May.
Ingenuity will not be the first spacecraft to soar through another planet’s atmosphere. That distinction falls to a pair of balloons that traversed the skies of Venus in 1985, collecting weather data as part of the Soviet-era Vega missions. But Ingenuity will attempt the first powered flight on another world, a Wright Brothers moment for the 21st century.
After dropping off the helicopter, Perseverance will retreat at least 100 yards away—far enough to avoid being hit in case Ingenuity crashes but still sufficiently close for radio communications. Its maximum of five flights will take place within a 30-Martian-day span, after which the rover will turn to its primary mission: assessing the habitability of Jezero Crater and caching samples of rocks and soils that may contain microfossils or other evidence of past microbial life.
During the final test, Ingenuity could fly up to 150 feet away, perhaps reaching its modest maximum altitude before returning to its takeoff point. “Because this is a pathfinder, we don’t have a hazard-detection-and-avoidance system,” Aung says. “That would be essential for future helicopters, because right before you land, you would want a three-dimensional, digital elevation map to be able to divert away and avoid any hazard.”
The most important flight test on Mars will be the first, which will replicate ones previously conducted inside a 25-foot diameter vacuum chamber at JPL. “We take off, hover, do a modest lateral flight, come back and land,” Aung says. “It’s extremely important, because it confirms all our models—all the tests that we’ve done on Earth.”
After that trip, Ingenuity’s flights should get a little bolder, with the rotorcraft traveling higher and then laterally farther before returning to land. “There’s a saying in the aviation community that the only thing more exciting than taking off in your own aircraft is landing it again,” says Håvard Grip, Ingenuity’s lead pilot. “I think that’s the case here.”
Ingenuity is one of three technology demonstrations planned for the Mars 2020 mission. The second is an autonomous hazard-avoidance navigation system that Perseverance will use during its descent to the 28-mile wide Jezero Crater. And the third is an instrument called the Mars Oxygen In-Situ Resource Utilization Experiment (MOXIE), which will attempt to convert carbon dioxide pulled from the atmosphere into oxygen, a resource for potential future human missions to Mars.
UFOs have been back in the news because of videos initially leaked, and later confirmed, by the U.S. Navy and officially released by Pentagon that purportedly show “unidentified aerial phenomena” (UAP) in our skies. Speculations about their nature have run the gamut from mundane objects like birds or balloons to visitors from outer space.
It’s difficult, if not impossible, to say what these actually are, however, without context. What happened before and after these video snippets? Were there any simultaneous observations from other instruments, or sightings by pilots?
Judging the nature of these objects (and these seem to be “objects,” as confirmed by the Navy) needs a coherent explanation that should accommodate and connect all the facts of the events. And this is where interdisciplinary scientific investigation is needed.
The proposal to scientifically study UAP phenomena is not new. The problem of understanding such unexplained UAP cases drew interest by scientists during the 1960s, which resulted in the U.S. Air Force funding a group at the University of Colorado, headed by physicist Edward Condon, to study UAP from 1966 to 1968. The resulting Condon Report concluded that further study of UAP was unlikely to be scientifically interesting—a conclusion that drew mixed reactions from scientists and the public.
Concerns over the inadequacy of the methods used by the Condon Report culminated with a congressional hearing in 1968 as well as a debate sponsored by the American Association for the Advancement of Science (AAAS) in 1969 with participation by scholars such as Carl Sagan, J. Allen Hynek, James McDonald, Robert Hall and Robert Baker. Hynek was an astronomy professor at the Ohio State University and led the Project Blue Book investigation, while McDonald, who was a well-known meteorologist and a member of the National Academy of Sciences (NAS) and AAAS, performed a thorough investigation of UAP phenomena. Sagan, a professor of astronomy at Cornell University, was one of the organizers of the AAAS debate. He dismissed the extraterrestrial hypothesis as unlikely but still considered the UAP subject worthy of scientific inquiry.
Recent UAP sightings, however, have so far failed to generate similar interest among the scientific community. Part of the reason could be the apparent taboo around UAP phenomena, connecting it to the paranormal or pseudoscience, while ignoring the history behind it. Sagan even wrote in the afterword of the 1969 debate proceedings about the “strong opposition” by other scientists who were “convinced that AAAS sponsorship would somehow lend credence to ‘unscientific’ ideas.” As scientists we must simply let scientific curiosity be the spearhead of understanding such phenomena. We should be cautious of outright dismissal by assuming that every UAP phenomena must be explainable.
Why should astronomers, meteorologists, or planetary scientists care about these events? Shouldn’t we just let image analysts, or radar observation experts, handle the problem? All good questions, and rightly so. Why should we care? Because we are scientists. Curiosity is the reason we became scientists. In the current interdisciplinary collaborative environment, if someone (especially a fellow scientist) approaches us with an unsolved problem beyond our area of expertise, we usually do our best to actually contact other experts within our professional network to try and get some outside perspective. The best-case outcome is that we work on a paper or a proposal with our colleague from another discipline; the worst case is that we learn something new from a colleague in another discipline. Either way, curiosity helps us to learn more and become scientists with broader perspectives.
So, what should be the approach? If a scientific explanation is desired, one needs an interdisciplinary approach to address the combined observational characteristics of UAP, rather than isolating one aspect of the event. Furthermore, UAP phenomena are not U.S.-specific events. They are a worldwide occurrence. Several other countries studied them. So shouldn’t we as scientists choose to investigate and curb the speculation around them?
A systematic investigation is essential in order to bring the phenomena into mainstream science. First, collection of hard data is paramount to establishing any credibility to the explanation of the phenomena. A rigorous scientific analysis is sorely needed, by multiple independent study groups, just as we do for evaluating other scientific discoveries. We, as scientists, cannot hastily dismiss any phenomenon without in-depth examination and then conclude the event itself is unscientific.
Such an approach would certainly not pass the “smell test” in our day-to-day science duties, so these kinds of arguments similarly should not suffice to explain UAP. We must insist on strict agnosticism. We suggest an approach that is purely rational: UAP represent observations that are puzzling and waiting to be explained. Just like any other science discovery.
The transient nature of UAP events, and hence the unpredictability about when and where the next event will happen, is likely one of the main reasons why UAP have not been taken seriously in science circles. But, how can one identify a pattern without systematically collecting the data in the first place? In astronomy, the observations (location and timing) of gamma-ray bursts (GRBs), supernovae and gravitational waves are similarly unpredictable. However, we now recognize them as natural phenomena arising from stellar evolution.
How did we develop detailed and complex mathematical models that could explain these natural phenomena? By a concerted effort from scientists around the world, who meticulously collected data from each occurrence of the event and systematically observed them. We still cannot predict when and where such astronomical events will occur in the sky.
But we understand to an extent the nature of GRBs, supernovae and gravitational waves. How? Because we have not dismissed the phenomena or the people who observed them. We studied them. Astronomers have tools, so they can share the data they collected, even if some question their claim. Similarly, we need tools to observe UAP; radar, thermal, and visual observations will be immensely helpful. We must repeat here that this is a global phenomenon. Perhaps some, or even most, UAP events are simply classified military aircraft, or strange weather formations, or other misidentified mundane phenomena. However, there are still a number of truly puzzling cases that might be worth investigating.
Of course, not all scientists need to make UAP investigation a part of their research portfolio. For those who do, discarding the taboo surrounding this phenomenon would help in developing interdisciplinary teams of motivated individuals who can begin genuine scientific inquiry.
A template to perform a thorough scientific investigation can be found in James McDonald’s paper “Science in Default.” While he entertains the conclusion that these events could be extraterrestrials (which we do not subscribe to), McDonald’s methodology itself is a great example of objective scientific analysis. And this is exactly what we as scientists can do to study these events.
As Sagan concluded at the 1969 debate, “scientists are particularly bound to have open minds; this is the lifeblood of science.” We do not know what UAP are, and this is precisely the reason that we as scientists should study them.
The views and opinions expressed in this article are those of the authors and are not necessarily those of NASA or their employers.
A hairlike, translucent creature that builds colonies on hermit crab shells is strange enough in appearance and living arrangements, but hydractinia’s oddities do not stop there. Scientists have now pinpointed a key gene—one also found in humans—that triggers this ocean floor dweller’s rare ability to make an unlimited supply of sperm and eggs. It is the first time a gene has been confirmed to solely activate an organism’s germ cell production, the researchers say.
Biologist Timothy DuBuc’s laboratory at Swarthmore College is one of a handful studying hydractinia, which has multiple genes in common with humans. DuBuc and his collaborators tested new ways to snip a gene called Tfap2 from the embryonic animal’s DNA and manipulate its activity in particular cells, as reported in February in Science. Hydractinia’s translucent body let the researchers easily observe the effect of removing the gene: once mature, the animal did not produce eggs and sperm. The team also confirmed that the gene’s activation in adult hydractinia stem cells turns them into germ cells (precursors of sperm and eggs) in an endlessly repeating cycle.
Cassandra Extavour, a developmental biologist at Harvard University, who was not involved in the research, calls the study’s technical advances a “heroic feat.” She says the work introduces multiple ways to interfere with hydractinia gene function, as well as the most robust gene-editing protocol to date for cnidarians—hydractinia and their relatives, including jellyfish and anemones.
In other animals scientists have investigated, Tfap2 triggers germ cells only during embryonic development—and the gene is involved in myriad other developmental processes, too. In humans, Tfap2 sparks a set number of germ cells just once during development, allowing sperm and egg production. Losing these germ cells results in sterility, and disruption of Tfap2 has been implicated in maladies such as testicular and ovarian cancer. Watching the gene in action could help researchers better understand and treat human reproductive conditions, according to the study authors.
“For those of us interested in finding the core program that makes a germ cell,” DuBuc says, “this could be the animal to do it.”
On April 1 Internet readers were treated to an announcement that appeared to come from Google CEO Sundar Pichai: “Today Google Stops Funding Climate Change Deniers.” It explained that Google—the world’s preeminent information company—had for many years financed disinformation, but the COVID-19 crisis had made it take stock. Google executives would “stop our funding of organizations that deny or work to block action on climate change.”