scroll to top
Stuck on your essay?
Get ideas from this essay and see how your work stacks up
Word Count: 10,198
Introduction Earth probably began about 45 billion years ago A history of this life on Earth is recorded in fossil remains and traces of past life It is a record of evolution for both life and the planet Life and the planet have co-evolved with life causing changes to the planet which in turn drive changes in life The Fossil Record A history of these changes is recorded in the layers or strata of rock laid down over the millions of years and by changes in the groups of fossils found in these rocks Scientists learn about extinctions by studying the fossil record and the chemical composition of rocks and chemicals around fossil excavation sites Looking at the relative abundance of fossil families in a rock layer indicates whether or not plant and animal families in the world at that time were thriving and diversifying or in decline A mass extinction will appear in the rock layers as a dead zone containing only a few fossil remains between layers with evidence of extensive life above and below it The dead zone represents the time of a mass extinction and its aftermath The study of extinctions is based on the fossil record which is incomplete and skewed This is due to the fact that not all fossils can be found or have been preserved over this long period of time There are probably many organisms that we dont even know about because we didnt find any of their remains Fossils are any preserved remnant or impression left by an organism that lived in the past Sedimentary rocks are the richest sources of fossils The fossil record documents macroevolution Macroevolution is the story of the major events in the history of life that are revealed by the fossil record The fossil record is a primary source of information for evaluating the history of life While the fossil record is unique in
@Kibin is a lifesaver for my essay right now!!
- Sandra Slivka, student @ UC Berkeley
Wow, this is the best essay help I've ever received!
- Camvu Pham, student @ U of M
If I'd known about @Kibin in college, I would have gotten much more sleep
- Jen Soust, alumni @ UCLA