A great hammerhead shark’s two eyes can be 3 feet apart on opposite sides of its skull.
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The first hammerhead shark was likely the result of a genetic deformity. A biologist explains how shark DNA reveals hammerheads’ history.
Reconstruction of Haikouichthys ercaicunensis based on fossil evidence.
Talifero/Wikimedia Commons
A biologist explains how researchers nail down the age of ancient fossils thanks to a physical process called radioactive decay.
A nanographene molecule imaged by noncontact atomic force microscopy.
Patrik Tschudin/gross3HR/Wikimedia Commons
A physicist explains how atoms arrange themselves into molecules – and how scientists are able to image these tiny bits of matter that make up everything around you.
The core of education is to enable young learners to be kind, giving members of society.
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The core principle of education is to enable students to become kind, giving and contributing members of their community and the world.
During ice ages, ice sheets like the one in Greenland have covered much of Earth’s surface.
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The Earth has had at least five major ice ages, and humans showed up in time for the most recent one. In fact, we’re still in it.
Roaming the ancient seas eons ago, the megalodon shark eviscerated its prey with jaws that were 10 feet wide.
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A terrifying sight in ancient waters, the megalodon shark was once the most feared creature in the sea.
President William Howard Taft and his wife rode in this steam-powered automobile in 1909.
AP Photo
This technology, popular when automobiles first caught on, had a short resurgence in the 1970s.
The Moon often looks enormous when it first rises because of what is known as the Moon illusion.
Roadcrusher/Wikimedia Commons
The Moon illusion is what makes the Moon look giant when you see it rising over a distant horizon. An astronomer explains what causes this awe-inspiring trick of the mind.
Plastic trash accumulates in trees and shrubs along the Los Angeles River.
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Plastic is made from oil and natural gas, which started out as fossilized plant and animal material. But buried deep underground for millions of years, those materials changed in important ways.
Interior view of Polito’s Royal Menagerie, Exeter Change, Strand, Westminster, London, 1812.
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Historians aren’t sure exactly when the first zoo was built, but it’s clear humans have kept exotic animals for thousands of years.
An artist’s concept of an astronaut walking on Mars. But what would happen if the astronaut weren’t wearing a space helmet?
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Mars is the fourth planet from the Sun and one of our closest neighbors in space. But it’s not a very welcoming place for an Earthling to visit.
Don’t call them tentacles: An octopus has eight arms.
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With nine brains, blue blood and a talent for camouflage, the octopus is one of the most fascinating creatures in the sea.
A tornado in Turkey, Texas.
Jana Houser
You can’t photograph the inside of a twister, but radar offers some clues.
The depths of the valleys on a key act like a code that must match the lock.
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A computer security expert explains how keys work – and how they are like passwords.
The Earth viewed from the Apollo 8 lunar mission on Dec. 24, 1968.
NASA
The Earth is a resilient planet, but people are altering it in ways that may take centuries to reverse.
The same thing that makes their eyes glow helps cats see better in dim light.
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A veterinary ophthalmologist explains what’s going on.
Pluto, the largest of the dwarf planets. This image was taken by NASA’s New Horizons spacecraft.
NASA/JHUAPL/SwRI
The dwarf planets in our Solar System are cold, dark, far away and full of surprises.
Artist’s rendering of the Chicxulub asteroid entering Earth’s atmosphere 66 million years ago, triggering events that caused a mass extermination.
Roger Harris/Science Photo library via Getty Images
Cockroaches have been on Earth far longer than humans and may outlast us. Here are a few reasons why.
English theatrical productions had all-male casts in the olden days.
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It may have had something to do with protecting female purity. No official statute clearly required men to do all the acting back then.
Murmurations can have as many as 750,000 birds flying in unison.
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These coordinated movements of a flock of starlings follow no plan or leader. Scientists used to think the animals must communicate via ESP to create these fast-moving blobs.