Radiometric dating lesson activities
Gymnosperm (meaning 'naked seed') groups evolved during the upper Paleozoic (the era prior to the Mesozoic) and included conifers (a familiar conifer would be a pine tree) and cycads (which look like palms and have leaf-like reproductive organs). During the Jurassic, the climate of most land was tropical and dinosaur species filled most ecological roles, including herbivores and carnivores.
Some reached enormous sizes, which is probably an indication of the abundance of vegetation (food for herbivores).
The universe is full of naturally occurring radioactive elements.
Radioactive atoms are inherently unstable; over time, radioactive "parent atoms" decay into stable "daughter atoms." When molten rock cools, forming what are called igneous rocks, radioactive atoms are trapped inside. By measuring the quantity of unstable atoms left in a rock and comparing it to the quantity of stable daughter atoms in the rock, scientists can estimate the amount of time that has passed since that rock formed.
Terrestrial vegetation was still dominated by ferns, cycads, gingkos, and conifers - all gymnosperms.Mammals began as tiny animals (like a mouse), and did not diversify or become very important until after the end of the Mesozoic Era.Terrestrial plants, or plants that live on land, were primarily dominated by gymnosperms. In this Brain POP movie on carbon dating, Tim and Moby will teach you about how scientists use a radioactive isotope called carbon-14 to find out the answer!Learn about key terms like half-life, radioactive decay, and radiometric dating and what they all mean!