While doing a paleontology assignment related to dating the age of a fossilized hair or bone, one tends to forget that all the dating methods have their limitations. Many paleontology students make this common mistake because of the lack of knowledge about geography, history, radioactivity, and chemicals. Here are the limitations of each dating method that a student needs to keep in mind.
Dating Techniques in Paleontology
Paleontology is a study of fossils to get a glimpse in the past life that flourished, evolved, and got extinct from this planet. There have been many mass extinction incidents that have happened on earth like the ice age, volcanic eruptions, meteorite hits, etc. Almost 99% of all the species that have lived on earth have gone extinct. This has created a massive amount of fossils that need to be unearthed and dated.
Dating of fossils is important to time tag a fossil and its content to establish a timeline of the history of evolution on earth. It is also done to study the period and climate in which that fossil was formed. It also gives us sneak peek in the past and study the effects of climate change on the organisms living at that time.
Over time dating techniques have been developed for this purpose, and there are three basic techniques. But, we can’t fully rely on any of these techniques, and they must be used in unison to get an exact time period.
Dating Techniques: Types and Limitations
Stratigraphy: This method involves the study of layers of sediment deposited over time and dating fossils found in them according to it. It can be applied over an unlimited period of time, but due to partial erosion and subsequent deposition, new layers are deposited between the older ones. One must be careful about the age of sediment layers while using this method and know the region’s geographical event history. Geographical activities like earthquakes, landslides, tidal waves, etc. also change the structure of these layers.
Biostratigraphy: Some extinct organisms only existed for a short period of time and got extinct. If found in rock and other organisms, the remains of these organisms tell us when that fossil was formed. Also, its position in the sediment layer gives us a fair estimate about the formation time of layers above and below it. This method is limited because at least one of the many fossils is found in the same region, and the sediment layer must have a known time period. Suppose an organism A existed only between the X-Y century and found in a rock layer with other fossils. This means all of them got buried between the X-Y century, and that layer was created.
Carbon Dating: This method involves studying the radioactivity of Carbon-14 present in the fossil. Carbon-14 content decreases over time in fossils because it decays over time. The percentage of remaining carbon with respect to its bi-products gives us the time when that organism died. This method is most accurate of all three, but it has a huge limitation. One can’t date a fossil using carbon dating beyond a period of 60,000 years. Carbon-14 has a half-life of 5730 years, meaning half of it will get decayed in this time, half of the remaining will again decay at the same time, and so on, its percentage gets reduced to beyond detection in about 60,000 years.
Conclusion
All dating methods used in the field have their limitations and must be kept in mind while writing a paleontology assignment where the time period of a fossil has to be determined. It is important to know that all these methods can be used simultaneously to get an exact figure.
Summary: The article explains the limitations of various dating techniques regarding fossils. This data is used to time tag samples collected in the field for writing a paleontology assignment. Also, to maintain accuracy, one has to use techniques based on conditions in which the fossil is found. If you feel the need for expert guidance with assignment, feel free to contact Paleontology Assignment Writing service providers at Assignment Desk
Author’s Bio: Chris is working as an academic writer with Assignment Desk for the past 5 years. He provides assignment writing help to students enrolled around the world. He is an avid researcher and a historian of evolution progress. He also likes collecting bones of extinct animal life and fossils of plants. He maintains an elaborate record evolution on earth.