Attention deficit hyperactivity disorder, a neurodevelopmental disorder characterized by inattention, hyperactivity, and impulsivity, is usually diagnosed during the early school years. (In order to be diagnosed with ADHD, symptoms must have begun before the age of 12.) But ADHD doesn’t always go away when you open your first 401(k). For many people, symptoms continue throughout life.Though researchers have long known that ADHD is a lifespan disorder, for many years, it was thought that about ...read more

At an auction in England in 2011, one of John Lennon’s teeth sold for just over US$31,000.How much are your teeth worth?Teeth are amazing little miracles. They light up our smiles, we use them to speak and we chew with them more than 600 times at every meal.Yet, in a society where 1 out of 5 Americans ages 75 and up live without their teeth, many people may not realize that teeth are designed to stay with us for a lifetime.I’m a dentist and an assistant professor spanning clinical dentistry ...read more

Partitioning history into multiple ages has helped us comprehend human developments and events throughout time, but what decides when one age transitions to the next? It turns out that the answer isn’t so clear-cut. Civilizations across the ancient world progressed at varying rates, complicating the task of drawing a clean divide between ages.Scholars have relied on overarching themes, though, to explain how human history changed trajectory over time. This is embodied by the three ages of preh ...read more

The traditional accounts of Aztec sacrifice are almost too gory to be true. In them, Aztec priests cut beating hearts from the chests of sacrificial victims before throwing them down the steep steps of pyramids. “It is the most terrible and frightful thing,” an account from 1519 stated, shortly after the Spanish arrival in Mesoamerica.But the Aztecs, or Mexica, whose empire controlled most of central Mexico in the 15th century, didn’t see sacrifice as quite so startling, nor as quite so si ...read more

Back in 2019, a group of computer scientists performed a now-famous experiment with far-reaching consequences for artificial intelligence research. At the time, machine vision algorithms were becoming capable of recognizing a wide range of objects with some recording spectacular results in the standard tests used to assess their abilities. But there was a problem with the method behind all these tests. Almost all the algorithms were trained on a database of labelled images, known as ImageNet. Th ...read more

Conspiracy theories are everywhere, and they can involve just about anything.People believe false conspiracy theories for a wide range of reasons– including the fact that there are real conspiracies, like efforts by the Sackler family to profit by concealing the addictiveness of oxycontin at the cost of countless American lives.The extreme consequences of unfounded conspiratorial beliefs could be seen on the staircases of the U.S. Capitol on Jan. 6, 2021, and in the self-immolation of a protes ...read more

If you’ve ever had the misfortune to swallow a mouthful of seawater, you have some idea of its intense salinity. One small gulp is bad enough, but the total salt content of Earth’s oceans is truly staggering: Based on an average of 7 tablespoons per liter, scientists have calculated that they hold about 50 quadrillion tons (that’s 15 zeros) of dissolved salt.More incredible still, it wasn’t always there. It trickled slowly into the ocean — grain by grain, year by year — from the moun ...read more

Many medical organizations have been recommending lung cancer screening for decades for those at high risk of developing the disease.But in 2022, less than 6% of people in the U.S. eligible for screening actually got screened. Compared with other common cancer screenings, lung cancer screening rates fall terribly behind. For comparison, the screening rate in 2021 for colon cancer was 72%, and the rate for breast cancer was 76%. Why are lung cancer screening rates so poor?I am a pulmonologist who ...read more

Wouldn’t it be great to be able to know someone’s next move and beat them to it? It’s the key to winning a game of chess, negotiating a deal, or winning a round of poker. It makes us better at the tasks at hand, but it may also be that we were better at these skills in the first place.According to research, expertise lays the groundwork when it comes to thinking farther ahead. The more skill you have in something like chess, the better equipped you are to think steps farther ahead when com ...read more

Shorebirds fly thousands of miles each year along ancient and largely unknown migratory routes called flyways. But their populations are crashing amidst climate change and urban development. Global Big Day, on May 11, is your opportunity to get involved during this momentous global migration and help scientists understand how bird populations are changing. Participate in the projects we’ve curated for you below and watch the extraordinary film Flyways, produced by SciStarter partner HHMI Tangl ...read more