A fly regurgitating digestive juices.
Carlos Ruiz
A fly does some of its digesting outside its body before it even eats any food.
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It can get very cold in space.
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Energy isn’t really made of anything else. It’s a kind of capacity to do things
Three upright walkers, including Lucy (center) and two specimens of Australopithecus sediba , a human ancestor from South Africa dating back nearly 2 million years.
Image compiled by Peter Schmid and courtesy of Lee R. Berger/Wikimedia Commons
Walking has taken a very long time to develop, with evidence of bipedalism among early humans in Africa roughly 4.4 million years ago.
A Japanese Sea Nettle jellyfish moves through the ocean.
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Most jellyfish are “passive” feeders. This means that they float through the water eating whatever they happen to pass in the water and can fit in their mouths.
On average, two students in every U.S. classroom have ADHD.
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Even when the condition lasts a lifetime, there are behavioral treatments and prescription drugs that make it easier for people with attention-deficit hyperactivity disorder to thrive.
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The sky on other planets doesn’t look the same as the sky on Earth does. And that’s because of the different gases in Earth’s atmosphere.
The Aurora Australis, or Southern Lights, reflected in the water.
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A curious kid asks: Why are the northern lights only spotted at areas around the poles?
Your teeth will be better off if you refrain from chomping on ice cubes.
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A dentist explains why this is a habit worth breaking – no matter the cause or the strength of your cravings to keep doing it.
The collective memory of school desegregation is of anger and division, like in this photo of 15-year-old Elizabeth Eckford walking away from a crowd outside a high school in Little Rock, Ark.
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Americans’ collective memory of school desegregation involves crowds of screaming white protesters. But less well known are the whites who stood by quietly, and those who approved of the changes.
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Understanding your genes is a great way to understand certain things about yourself — yet, who we are is determined by so much more than just DNA.
The American Academy of Pediatrics says teens should never consume energy drinks.
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Energy drinks and coffee both contain lots of caffeine. That’s a problem for teens, especially those who take prescription stimulants.
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Like the lazy koala, the reason sloths go slow has a lot to do with what they eat.
Astronomers have found a way to estimate the number of stars in the universe.
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Scientists have a good estimate on the staggering number of stars in the universe.
That pins-and-needles feeling can come from sitting in the same position for a while.
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An exercise physiologist explains how it’s a problem of communication between your brain and your body.
The Earth is round.
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Gravity, mass and centrifugal force all contribute to the final shape of a planet.
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The temperature of the Sun’s surface is about 6,000°C. But higher above the surface, in the atmosphere, it suddenly shoots up to more than a million degrees!
COVID-19 vaccines have been proved safe and effective. But it’s understandable to have questions.
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An infectious disease doctor explains the science behind COVID-19 vaccines at a level that children – and adults – of all ages can understand.
Planting 8 billion trees a year would replace about half of the 15 billion cut down annually.
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Planting a massive number of trees can help slow climate change, but it is only part of the solution.
Tyrannosaurus rex was a relentless predator who lived during the Cretaceous Period more than 65 million years ago.
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Ever since moviegoers saw the first ‘Jurassic Park,’ millions have wondered if scientists could make a dinosaur in the lab.