August 22, 2024: Solar-powered regenerating worms, people believe there's no such thing as a free lunch, and the artificial sweetener erythritol may contribute to blood clots. —Andrea Gawrylewski, Chief Newsletter Editor | | | The green coloring on this acoel comes from symbiotic algae. Eric Röttinger | | | Many worms can regenerate into two new worms if they're cut in half. Deepsea flatworms called acoel regenerate into three new worms if they're severed in two. Plus, they have a symbiotic relationship with algae living inside their bodies that provide energy through photosynthesis. Researchers found that, when regenerating after being sliced, the worms can control the genetics of their algal partners to regulate the algae's photosynthesis.
How it works: While the worms are regenerating into new forms, a worm gene called runt turns on and makes proteins that aid in regeneration. That same protein likely helps switch on genes in the algae symbionts to turn up their level of photosynthesis to compensate for the loss of efficiency while the host worm regrows.
What the experts say: "The photosynthetic pathway being controlled by the regenerative program of the host—that was the most surprising thing for us," says Bo Wang, a developmental biologist at Stanford University. Learning how hosts control their algal partners could help researchers manipulate the algae within corals stressed by rising ocean temperatures that have lost interactions, he says. | | | Psychologists surveyed thousands of participants and found that people will turn down unusually high salaries, remarkably cheap services or "free money" because the deals seem "too good to be true." And the higher potential monetary gain the less chance the participants would accept the offer. It seems most people have fully bought into the economic acronym TINSTAAFL (there is no such thing as a free lunch).
Why this is interesting: The "standard economic model" assumes that humans always want to maximize their gains no matter what. But this new research suggests that financial transactions have a social component; if an offer or someone's overgenerosity seems to violate the norms, most people assume there are "phantom costs," or an ulterior motive at work.
What the experts say: "Understanding that others' perceived overgenerosity may put us in their debt could also help explain people's reluctance," says Rachel McCloy, a psychologist studying decision-making at England's University of Reading. "The old maxim 'there's no such thing as a free lunch' is clearly alive and well." | | | • Members of the U.S. congress whose ancestors enslaved people have a higher median net worth than those whose ancestors did not. | 5 min read | | | • Houston, Tex., is experiencing a spike in West Nile virus cases, fueled by heavy spring rains and wet and warm conditions. | 3 min read | | | • A play in London called Kyoto tells the story of the Kyoto Protocol, an agreement made in 1997 that committed both industrialized countries and developing economies to limit their greenhouse gas emissions. "It's a very strange experience to watch a play in which you are a character," writes Ben Santer, a climate scientist who was a key figure in all six Intergovernmental Panel on Climate Change's scientific reports that informed many climate conferences. Santer's research on climate fingerprinting, which helped track carbon sources in the atmosphere and definitively showed that humans were causing unprecedented global warming, was crucial to the treaty. "Kyoto tells the story of how that scientific understanding evolved and how powerful vested interests tried to destroy it," he says. | 6 min read | | | From the July 1974 issue of Scientific American, the molecular structure of the enzyme trypsin (blue), attached to a substrate material (red) being cleaved. The authors wrote: "Trypsin and a substrate fit together like pieces of a three-dimensional jigsaw puzzle." Trypsin is an enzyme that aids with digestion by breaking chains of amino acids in proteins. | | | It seems we're only beginning to discover the incredible ways that organisms harvest the sun. Earlier this summer researchers reported the highest efficiency solar panel on Earth in the photosynthetic algae living symbiotically in a giant clam's innards (you can't make this stuff up!). I'm optimistic that humans will soon devise entirely new techniques to take advantage of the approximately 173,000 terawatts of solar energy continuously striking the Earth. | Thank you for being part of our circle of science-curious readers! Email me anytime: newsletters@sciam.com. See you tomorrow. | —Andrea Gawrylewski, Chief Newsletter Editor | | Subscribe to this and all of our newsletters . | | | | Scientific American
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