SPONSORED BY  | | | | January 24, 2024: Species are constantly evolving even when they seem to stay the same, state of the world's aquifers and what it really takes to form a new habit. —Andrea Gawrylewski, Chief Newsletter Editor | | | Still Changing After all These Years | Even though some species appear to remain unchanged over millions of years (like the the coelacanth, a modern-day fish, that is nearly identical to its 410-million-year-old fossilized counterparts), they are evolving to have new traits each generation that come and go, depending on what enables the most success in the current environment. Researchers studied four anole lizard species, all of which have remained relatively unchanged for 20 million years, living on a small island in Florida's Fairchild Tropical Botanic Garden. The "best" traits in each generation changed–for example, some generations' short-legged lizards survived better, while in other generations more individuals with sticky toes survived.
Why this is interesting: Evolutionary scientists have long thought that the pressures of natural selection keep selecting for so-called moderate traits (middle of the spectrum traits), resulting in species that seem unchanged for long periods of time. This new study shows a dynamic response to selection pressures, leading to more extreme traits to support short-term survival. Over the long term these extremes cancel each other out, the researchers hypothesize.
What the experts say: These observations are "a good explanation for why we see what we think is stabilizing selection," says Tadashi Fukami, an ecologist studying evolution at Stanford University, referring to the selection of the same, moderate traits. Many new traits are evolving in the short term, but they don't provide a crucial advantage over the long term. | | | Aquifers around the world are drying up. A third are depleting faster than ever before: 36 percent of aquifers are losing water at more than 0.1 meter per year, and 12 percent are declining at more than 0.5 meter per year. Researchers collected wellhead monitoring data from 170,000 wells in 1,693 aquifer systems in more than 40 countries. This is the first study to combine precise, on-the-ground monitoring with a worldwide scope, they say.
Important caveats: Not all groundwater is vanishing. In many places where humans have made important usage and policy decisions to conserve water, aquifers have maintained, or even rebounded in some cases. Groundwater pumping fees or finding other sources of water entirely can decrease overall aquifer usage.
What the experts say: Such changes can be controversial, says Sherrel Johnson, projects manager for the Union County Water Conservation Board in Arkansas. She spearheaded efforts to implement water pumping fees and a tax program to build the infrastructure to tap the nearby Ouachita River instead of the rapidly draining Sparta Aquifer. After implementing changes, the aquifer has rebounded by 36 meters since 2004. | | | Heavily cultivated areas in arid and semi-arid regions have far more depleted aquifers. Credit: Amanda Montañez; Source: "Rapid Groundwater Decline and Some Cases of Recovery in Aquifers Globally," by Scott Jasechko et al., in Nature. Published online January 24, 2024 | | | • A common myth says it takes 21 days to form a habit. But making new behaviors stick is different for everyone, experts say. | 5 min read | | | • Animals can see light with higher frequencies than humans, and scientists have devised a new video technique to help us get a sense of what it looks like. | 5 min read | | | A butterfly through the eyes of a bird. Credit: "Recording Animal-View Videos of the Natural World Using a Novel Camera System and Software Package," by Vera Vasas et al., in PLOS Biology, Vol. 22, No. 1. Published online January 23, 2024 (CC BY 4.0) | | | • It's a long-standing government failure to never use federal "march-in" licensing rights to lower drug prices, writes James Love, director of the nonprofit Knowledge Ecology International. Announced in December, the White House's new policy to lower drug prices "avoids the core issue related to every past attempt to use march-in rights to address prices," he says. | 5 min read | | | SPONSORED CONTENT BY NOVAVAX | Novavax is a global leader in vaccine development and research | The company's vaccine technology is built on a protein-based platform and combines the power of a well-understood approach with an innovative nanoparticle technology. It is intended to help protect against some of the world's most pressing viral diseases. Learn More. | | | • Phage viruses are used in the rest of the world as an alternative to antibiotics and are less prone to resistance. Why aren't they used in the U.S.? | Ambrook Research | | | • This is what may have happened aboard the Space Shuttle Challenger mission in April 1985 when one crew member threatened mission control. | Ars Technica | | | • The U.S. Bureau of Land Management has opened 22 million acres of federal land for solar farms. | Electrek | | | Many cultures around the world in arid regions have ancient techniques for collecting and storing rainwater. Some of those simple tactics have made their way to the U.S., namely in hot and dry places like Arizona. By cutting segments out of curbs, excess rainfall can flow into adjacent soil and inadvertently "water" the vegetation there. Other techniques for maximizing rainfall storage: Rain barrels next to households; using treated sewage for agricultural irrigation; and recycled wastewater for non-potable uses (like toilets). The future demands smarter use of our most precious resource. | Email me anytime with feedback or suggestions for this newsletter: newsletters@sciam.com. Thanks for reading. | —Andrea Gawrylewski, Chief Newsletter Editor | P.S. Yesterday's newsletter item on sand mafias incorrectly referred to Nairobi as a country. Nairobi is the capital city of the country Kenya. | | Subscribe to this and all of our newsletters . | | | | Scientific American
One New York Plaza, New York, NY, 10004 | | | | | | Support our mission, subscribe to Scientific American | | | | | | | | | |
