Dinosaurs are a group of reptiles that have lived on Earth for about 245 million years. All non-avian dinosaurs went extinct about 66 million years ago. There are roughly 700 known species of extinct dinosaurs.

Tides are caused by gravitational pull of the moon and the sun. Tides are very long-period waves that move through the oceans in response to the forces exerted by the moon and sun. Tides originate in the oceans and progress toward the coastlines where they appear as the regular rise and fall of the sea surface.

tidal. Of or pertaining to tides; caused by tides; having tides; periodically rising and falling, or following and ebbing; as, tidal waters. ”The tidal wave of deeper souls Into our inmost being rolls, And lifts us unawares Out of all meaner cares.

High tides and low tides are caused by the moon. The moon’s gravitational pull generates something called the tidal force. The tidal force causes Earth—and its water—to bulge out on the side closest to the moon and the side farthest from the moon. When you’re in one of the bulges, you experience a high tide.

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Dinosaurs lived on all of the continents. At the beginning of the age of dinosaurs (during the Triassic Period, about 230 million years ago), the continents were arranged together as a single supercontinent called Pangea. During the 165 million years of dinosaur existence this supercontinent slowly broke apart.

The upshot: The earliest dinosaurs originated and diverged in what is now South America before trekking across the globe more than 220 million years ago when the continents were assembled into one gargantuan landmass called Pangea.

For decades, the prevailing theory about the extinction of the dinosaurs was that an asteroid from the belt between Mars and Jupiter slammed into the planet, causing cataclysmic devastation that wiped out most life on the planet. The gravity from Jupiter pulled the comet into the solar system.

The instantaneous devastation in the immediate vicinity and the widespread secondary effects of an asteroid impact were considered to be why the dinosaurs died out so suddenly. Asteroids are large, rocky bodies that orbit the Sun. They range from a few to hundreds of metres in diameter.

Non-bird dinosaurs lived between about 245 and 66 million years ago, in a time known as the Mesozoic Era. This was many millions of years before the first modern humans, Homo sapiens, appeared. Scientists divide the Mesozoic Era into three periods: the Triassic, Jurassic and Cretaceous.