More than 500 million years ago, strange, complex creatures appeared on Earth. Scientists now think they know why
Sign up for CNN’s Wonder Theory science newsletter. Explore the universe with news about fascinating discoveries, scientific advancements and more. Earth’s magnetic field plays an important role in making our planet habitable. The protective bubble above the atmosphere protects the planet from solar radiation, winds, cosmic rays and wild fluctuations in temperature. But new research… Read More »