Scientific American-Today in Science

"Voyager 1 is making sense again."

Views expressed in this science and technology update are those of the reporters and correspondents.  Accessed on 23 April 2024, 2309 UTC.

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Russ Roberts (https://hawaiisciencejournal.blogspot.com).

 

April 23, 2024: Time can stretch for humans, beetles live on a 48-hour sex schedule, and the Voyager spacecraft is making sense again. —Andrea Gawrylewski, Chief Newsletter Editor TOP STORIES Time Dilation Time seems to slow down when we see something memorable, scientists have found. Study participants looked at images for varying lengths of time, and then held down a key to indicate how long they felt they were looking at the image. For images that are inherently more memorable—a person’s face, for example—participants thought they looked at them for longer than they did. And they also remembered these time-warping images better the next day. Why this is cool: Time can seem to stand still in moments of impending danger, or fly by when you’re having fun. But there are also more subtle warping effects that we may not notice in daily life: for example, looking at red images stretches time compared with blue ones, same with bigger objects compared with small ones. The new research shows a new time-warp illusion that is fascinatingly circular: more memorable images last longer, and persistent images are remembered better. What the experts say: Neuroscientists still don’t understand where our subjective sense of time comes from, or why it expands and contracts. Martin Wiener, the senior author of the new study, thinks that the time-warp illusions could help our brains get around a “bottleneck” in its ability to take in new information in important situations. “It’s possible that the brain can widen the bottleneck when it needs to” to take in more information, he says. “And as a consequence of this, it dilates time.” –Allison Parshall A Hard Two-Day's Night Nearly all animals have 24-hour activity cycles based on genetically built-in circadian clocks. But black chafer beetles operate on a 48-hour timetable instead. And the schedule is driven by a strict schedule for sex. Researchers discovered the male beetles have a gene that codes for an odor receptor that is attuned to the female beetle's pheromones.  Why this is cool: Both male and female chafer beetles hide underground during the day and emerge every second night to search for food and a mate. Odor receptor production spiked at night every 48 hours around the time female pheromone production peaked, then hit a low the next night. “We found a 48-hour [receptor-producing] cycle, which is synchronized with the females,” says Walter Leal, a chemical ecologist at the University of California, Davis. “It’s a beautiful story.” What the experts say: Biological rhythms typically depend on day and night signals–there are no known 48-hour cues in nature. So the beetles must be responding to some other prompt. “The field is recognizing that the number of rhythms in biology is enormous,” says Jennifer Hurley, a biologist at Rensselaer Polytechnic Institute. TODAY'S NEWS • After months of garbled transmissions from Voyager 1, NASA has established clear and sensical communication with the spacecraft again. | 3 min read • Arizona and Florida courts recently passed strict restrictions on abortion. But voters in those states and others could have the final say this November, when abortion access will appear on the ballot. | 6 min read • The U.S. is paying hundreds of millions of dollars for sand to replenish storm-ravaged beaches that more storms just wash away. | 6 min read • Fossils and stone tools show that early humans sheltered in this lava tube in Saudi Arabia 10,000 years ago. | 3 min read Researchers exploring the Umm Jirsan Lava Tube system. Palaeodeserts Project (CC-BY 4.0) More News EXPERT PERSPECTIVES • Space junk is getting out of control. NASA estimates that low-Earth orbit alone contains 34,000 pieces of debris larger than 10 cm in diameter, 900,000 objects between 1 cm and 10 cm, and more than 128 million fragments between 1 mm and 1 cm. We need to take both passive and active measures before space junk makes Earth's orbital space unusable, write Aneli Bongers and José L. Torres, associate professor and professor, respectively, of macroeconomics at the University of Málaga.  | 5 min read More Opinion Humans are linear creatures. For us there is a definite "past" and a "future" that has yet to happen. This present moment we consider "real." But, as some physicists surmise, the experience of time is relative (and may even be an illusion). As Paul Davies, professor of theoretical physics at Arizona State University, wrote in an article in Scientific American 10 years ago, "Two events that occur at the same moment if observed from one reference frame may occur at different moments if viewed from another." Our apparent real moments are transmutable. Just ask the black chafer beetles who live in 48-hour increments.  Email me, no matter the time, at: newsletters@sciam.com. I read all your notes and respond to many. See you tomorrow. —Andrea Gawrylewski, Chief Newsletter Editor Subscribe to this and all of our newsletters here. Scientific American One New York Plaza, New York, NY, 10004   Support our mission, subscribe to Scientific American here   Unsubscribe Email Preferences

Scientific American-Today in Science

"Today in Science:  No one is coming to save us."

Views expressed in this science and technology update are those of the reporters and correspondents.  Accessed on 22 April 2024, 2040 UTC.

Content and Source:  scientificamerican.com.

Please scroll down to read your selections.  Thanks for joining us today.

Russ Roberts (https://hawaiisciencejournal.blogspot.com).

 

SPONSORED BY

April 22, 2024: Happy Earth Day! We're tracking human impact on Earth's systems, a genetic bank for endangered species and what happens when people quit Ozempic. —Andrea Gawrylewski, Chief Newsletter Editor

TOP STORIES

Pushing Boundaries As human populations and resource demands continue to grow, they put more pressure on Earth’s eight natural systems–for example, groundwater supplies, land area for wild animal habitats and ecosystems, and clean air. Scientists have determined how far these systems can be pushed until serious harm comes to the lifeforms that depend on those systems. But some experts argue that those limits must be made more conservative, in order to truly protect humans and the planet.  Case in point: Aerosols, or fine particulates less than 2.5 microns in diameter, are released into the air by a range of industrial processes. Their rising concentrations are starting to alter monsoon rain patterns on which millions of people depend for growing food. Such weather patterns are global. But aerosols can also harm human lungs, and people in poorer regions often suffer more from particulate pollution. A limit of 0.25 to 0.50 aerosol optical depth, or AOD, an estimate of the amount of aerosols present in the atmosphere, demarcates how much the atmosphere can accommodate before severe changes kick in. But a “safe and just” limit of 0.17 AOD, takes into account the problem of local air pollution levels, which kill millions of people a year.  What the experts say: “Our latest work indicates that in 2023 the world had already surpassed the safe and just limit for seven of the eight boundaries,” writes Joyeeta Gupta, a professor of environment and development in the Global South at the University of Amsterdam and a professor at IHE Delft Institute for Water Education. “Only the aerosols limit has not been breached globally, although local aerosol boundaries have been crossed in many parts of the world. We have also found that in more than 50 percent of all places on Earth, at least two of the safe and just boundaries have been crossed.”

Animal Biobank The U.S. Fish and Wildlife Service has teamed up with a nonprofit conservation company on a project to cryogenically store tissue from every endangered animal species in the U.S. The goal is to eventually collect tissue samples from at least one male and one female of each of the hundreds of endangered animal species in the U.S. So far in the so-called biobanking pilot project, the team has collected tissues from 13 endangered species, with a goal of 25 overall for the pilot phase. The samples are being stored at –256 degrees Fahrenheit at a U.S. Department of Agriculture cryogenic facility in Fort Collins, Colo. Why this matters: Much like the Svalbard Global Seed Vault in Norway, which has been collecting seeds from around the world since 2008, the founders of this project hope to keep a genetic library that might save some endangered animals from extinction. More than 1 million of Earth’s plant and animal species are at risk of extinction, and the rate is accelerating, according to a 2019 UN Report. The top causes are loss of habitat (deforestation), invasive species, and overhunting/overfishing. What the experts say: Biobanking is not a catch-all solution for biodiversity loss. Rather it is a single item in the recovery toolbox. “Some people think if you have [species] in a freezer, you don’t need them in the wild,” says Seth Willey, a FWS deputy assistant regional director who heads the project’s pilot phase. “That’s just not true.... We can’t lose what we have in the wild. But if we do, it’s good to have an insurance policy.” More Earth Day coverage:  How the Environment Has Changed since the First Earth Day 50 Years Ago | 5 min read How Deep Is Your Carbon Footprint?--Celebrate Earth Day with Data | 4 min read

This black-footed ferret (Mustela nigripes) is the first endangered species in the U.S. to ever be successfully cloned and came from a cryogenically preserved cell line. Kika Tuff/Revive & Restore (CC BY 4.0)

TODAY'S NEWS

• The Biden administration is marking Earth Week with grants for solar power for lower-income communities, an expansion of the Climate Corps and Clean Air Act rules. | 4 min read

• Human brains may be getting bigger. | 4 min read

• This is what happens when people quit taking weightloss drugs. | 7 min read

• Researchers discovered the fossils of a giant snake species that likely lived 47 million years ago and reached nearly 50-feet long. (*shudders*) | 3 min read

More News

EXPERT PERSPECTIVES

• “Climate havens” are areas touted by researchers, public officials and city planners as natural refuges from extreme climate conditions, and include the Great Lakes region, upper Midwest and upper Northeast. But these regions will not be immune to the severe impacts of climate change, write Julie Arbit, Brad Bottoms and Earl Lewis, all researchers at the Center for Social Solutions at the University of Michigan. On the contrary, cities in these locations will have to contend with some of the most extreme temperature and rainfall events to come, they say. | 5 min read

More Opinion

SPONSORED CONTENT BY ARIZONA STATE UNIVERSITY The conversation starts here. Our mandate is to keep the complex network of systems that make up our world in balance so that all life on Earth may thrive. This requires bringing all of our voices together to craft long-term, sustainable solutions. Join the conversation at globalfutures.asu.edu.

Every Earth Day (and often in between) I think of a segment from Carl Sagan's TV series "Cosmos." As a tiny blue dot grows into visibility on screen and becomes recognizable as Earth, Sagan tells us that the sum of all human experience, struggle, and joy has happened on our planet--a "very small stage in a vast cosmic arena." There is no indication, he says, "that help will come from elsewhere to save us from ourselves. The Earth is the only world known so far to harbor life." It was a message to his viewers (and even to us, 30 years later), that it is up to us to take care of the Earth and ourselves. This is our only home.

Thank you for caring for Earth by being a science lover! Reach out anytime with suggestions or feedback: newsletters@sciam.com. Until tomorrow!

—Andrea Gawrylewski, Chief Newsletter Editor

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