They are formed primarily on the cell's Ribosomes.
<span>If I were attempting to date a rock sample that I suspect to be incredibly old, i would use radioactive isotopes with a long half life. When dating rocks and fossils to discover approximately how old they are, radioisotope dating is used on igneous rocks found near fossils. Things like Uranium 235, which is an unstable radioactive isotope of elements, decays at a constant rate over time so can be useful in determining age.</span>
Chloroplasts are organelles found in plant cells that conduct photosynthesis. Chloroplasts absorb light and use it in conjunction with water and carbon dioxide gas to produce food for the plant.
The main type of evidence the scientists used is fossils.
Palaeontologists study plants and animals that existed in the geologic past. To do so, they use fossils and try to determine an organism's evolution and relationship with the environment and other organisms. In this example, palaeontologists used fossils from ancient horses that have gone extinct and try to decipher their evolutionary path. Recognising the evolutionary steps of the ancient horses will make it possible to compare them to the modern horses.
