After the dino-killer asteroid, rapid evolution helped life bounce back quickly
asteroid: A rocky object in orbit around the sun. Most asteroids orbit in a region that falls between the orbits of Mars and Jupiter. Astronomers refer to this region as the asteroid belt. atmosphere: The envelope of gases surrounding Earth, another planet or a moon. average: (in science) A term for the arithmetic mean, which is the sum of a group of numbers that is then divided by the size of the group. biology: The study of living things. The scientists who study them are known as biologists. Chicxulub: The name given an asteroid (or possibly a comet) that crashed into Earth around 66 million years ago. It left a crater more than 180 kilometers (110 miles) wide near the town of Chicxulub in what is now Mexico. The collision released an immense amount of energy — equivalent to billions of atom bombs the size of those dropped on Japan during World War II. This event changed the planet’s climate and is widely believed to have triggered a mass extinction of species — including the …






