Hobbies And Interests
Fossil Fuels
A fossil fuel is an energy resource that originates from long-dead materials. Millions of years ago, much of the Earth wasn't like it was today; it was more like the Everglades or Louisiana bayou, only everything was much bigger. When the plants, animals and insects died, they stacked up in the swamp and were covered by sand and clay. Geological action squeezed out the water from all the decaying matter as it became sedimentary rock. It took all this time to make our fossil fuels: oil (petroleum), natural gas and coal. Even if we buried tons of dead trees, plants and animals in a swamp to help it along, it would take several million years before anyone would have a fossil fuel again -- which makes it basically nonrenewable. It makes up 85 percent of the energy used by the United States, and almost all of the power we need for transportation and electricity.
History of Past Living Things
Scientists have studied fossils to obtain knowledge about what happened in the past. They don't just study dinosaurs or ancient mammals, though. They also study ancient people, ancient extinct plants, and even the Earth itself, and they carbon-date them to see how old they are. When it comes to past living things, fossils show how they may have died. A Tyrannosaur's tooth impression might be found on the bone of a duck-billed dinosaur to show that it was eaten. A burial site from pre-civilization might have the remains of a man in his 50s who was treated like a king. Learning how people and animals lived and died is beneficial to science, as it tries to construct how or why things have changed into the way they now are.
The Geography of Times Long Past
The Earth hasn't always looked as it does now. To figure that out, scientists looked at the fossils they found all over the world. They discovered that tortoises and alligators once lived on Ellesmere Island, just off the western shore of Greenland. What this told the scientists was that Ellesmere Island was once much warmer than it is currently. Farther back than that period, many of the continents of Earth were smashed together in a supercontinent called Gondwanaland. They know this because of the fossil record: they discovered a sea reptile called the mosasaur that could only be found near the tip of Africa and the tip of South America; land reptile Cynognathus, who lived from the heart of South America through the heart of Africa; another land reptile called Lystrosaurus, who lived in Africa, India and Antarctica; and an ancient fern, Glossopteris, that lived in every one of those continents plus Australia. Many fossils have been discovered whose range supports the theory of one great land mass.
The Biology of Extinct Organisms
Of course, fossils also tell us all about the biology of things that were alive long ago. Finding fossils of cockroaches from millions of years ago and comparing them with present-day roach species shows that not much in their bodies or their diets has changed over all this time. On the other hand, dinosaurs that walked on two legs, such as the T. rex, apparently began to change millions of years before the end of the dinosaur age, becoming more like birds until that's all that we have of them presently. The bones left behind show us what the creature probably ate, how it walked, whether it lived in groups and much more. Even humans, other animals and plants can have a fossil trail that scientists follow as far back as the beginning of each species.