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 | | | 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 | | | 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. | | | • 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 | | | Researchers exploring the Umm Jirsan Lava Tube system. Palaeodeserts Project (CC-BY 4.0) | | | • 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 | | | 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 . | | | | Scientific American
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