Fossils are the remains of animals or plants that lived a long time ago. When we think of fossils, the first things that come to mind are the bones of dinosaurs; but a fossil can be anything. Footprints, flowers, even droppings; all of these things can be turned into fossils under the right conditions. A fossil only becomes a fossil when it has reached a certain age. Though there is no one age, a good rule is anything over 10, years old can be considered a fossil. The oldest fossils ever discovered are more than 3.
What isotope pair used to determine the age of fossils
All about Fossils and Carbon Dating: Dinosaur Teeth and More for Kids
By: Marshall Brain. A child mummy is found high in the Andes and the archaeologist says the child lived more than 2, years ago. How do scientists know how old an object or human remains are? What methods do they use and how do these methods work? In this article, we will examine the methods by which scientists use radioactivity to determine the age of objects, most notably carbon dating.
How Do Scientists Determine the Ages of Human Ancestors, Fossilized Dinosaurs and Other Organisms?
A number of methods are used today to date fossils. Most of the methods are indirect meaning that the age of the soil or rock in which the fossils are found are dated, not the fossils themselves. The most common way to ascertain the age of a fossil is by determining where it is found in rock layers. In many cases, the age of the rock can be determined by other fossils within that rock. If this is not possible, certain analytical techniques are often used to determine the date of the rock layer.
When we speak of the element Carbon, we most often refer to the most naturally abundant stable isotope 12 C. Although 12 C is definitely essential to life, its unstable sister isotope 14 C has become of extreme importance to the science world. Radiocarbon dating is the process of determining the age of a sample by examining the amount of 14 C remaining against its known half-life, 5, years. The reason this process works is because when organisms are alive, they are constantly replenishing their 14 C supply through respiration, providing them with a constant amount of the isotope.