Paleontology/Radiometric Dating/Biogeography

Paleontology

The main part of paleontology are fossils. Fossils are composed of minerals that have been leftover from water that once surrounded the living matter. Fossils help us find different living organisms that may have once lived. It also help us find their different behaviour and if it changed it over time. Lots of information can be found through paleontology. Paleontologists find out where the species once lived and the different structures of many extinct animals. Paleontology is very important since it helps us find out what the earth may have looked like and what once lived here.

Radiometric Dating

Radiometric dating helps us find out how old fossils or rocks are and interpret an approximate date using radioactive isotopes. An atom of a fossil or a rock changes into a daughter isotope. This is called half-lives and helps us determine how many half-lives it takes for the isotope to decay. Paleontologists have discovered that these half-lives are usually consistent and are not affected by factors such as temperature or moisture. Without radiometric dating, it would be very hard for us to find out how old fossils are which helps us find out how long organisms have been living for. Radiometric dating is very useful for paleontologists.

Biogeography

There has been much distribution and variation of life throughout earth. This is called biogeography. Through the process of continental drift, the earth's continents have gone through dramatic changes and have moved over a period of about 225 million years. From what people have discovered, we can conclude that the earth's tectonic plates have moved from its original place. This helps us understand why certain species that used to live on one part of Earth's landmass (through fossils), now live completely on the other side of the ocean or someplace where it may have been impossible for the species to travel. Some species are endemic, meaning they were found in only one place. Biogeography has helped us understand many concepts that may have been confusing to us once.

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