According to the Utah Geological Survey, the first ice age occurred over 2 billion years ago. Ice ages are long periods of time when global temperatures are cold and many areas of the Earth are covered by continental ice sheets and alpine glaciers.
Ice ages can last tens of millions of years. There have been at least five major ice ages in the history of the Earth. Many factors can cause an ice age, including changes in atmospheric and ocean circulation, varying concentrations of atmospheric carbon dioxide or even volcanic eruptions. The 21st century Earth is currently in an ice age that began approximately 3 million years ago and peaked about 20,000 years ago.Learn More
Cro-Magnon man, now referred to as European Early Modern Humans, were hunter-gatherers who ate a varied diet containing hunted big game, fruits, nuts, berries, seeds, plants and roots. It is also known that they ate fish, insects and the prey left over from predators.Full Answer >
The Paleozoic Era saw changes to Earth's landscapes, life forms and atmosphere over the course of several million years. On land, at sea, below the surface and in the skies, change occurred throughout the six distinct periods comprising the Paleozoic Era. The early Paleozoic periods introduced many plant species, while later periods brought invertebrates, dinosaurs and birds.Full Answer >
Neanderthals lived from about 200,000 years ago until 28,000 years ago. They lived in Europe, as well as southwestern and central Asia, and are the closest extinct relative to modern humans.Full Answer >
Neanderthals (also spelled "Neandertals") were shorter and more stocky than homo sapiens. Their faces were also much larger and wider, and they sported a wider nose. These adaptations made it easier for them to live in colder environments.Full Answer >