Scientists estimate the ages of fossils using which of the following methods?

Fossil dating is primarily accomplished through methods such as radiometric dating and stratigraphy, which are scientifically validated techniques that provide accurate age estimates. Radiometric dating analyzes the decay of radioactive isotopes within the rocks surrounding the fossils, allowing scientists to determine the age of the fossil accurately based on the half-lives of these isotopes. Stratigraphy involves studying the layers of sedimentary rock where fossils are found, which can indicate relative ages based on the principle of superposition—wherein lower layers are typically older than those above them.

While visual inspection can provide certain insights into fossil morphology and potential age relationships, it lacks the precision necessary for accurate dating. Similarly, development of species characteristics can provide context about evolutionary changes over time but does not directly relate to determining the age of specific fossils. Comparative anatomy of extant species, while useful for understanding evolutionary relationships and anatomical changes, is not a method for dating fossils but rather a tool for studying lineage and mutation patterns. Thus, the method involving radiometric dating and stratigraphy stands out as the most reliable and scientifically recognized approach to estimating the ages of fossils.