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Trek Through Time for Kids!
3D Paper Models!
The Youth & Education in Science (YES) office has compiled the 3D paper models by T.R. Alpha and others that were created in the 1990s, and are now available downloadable PDFs from the hyperlinks in the next sentence. You can use any colors you like, fossils don’t tell us what color an animal was when it was alive, so you can use any colors you like! to print and color any way you like. Blue, underlined hyperlinks will take you directly to the downloads: You can find a trilobite and nautiloid from the Paleozoic, or a pterosaur and stegosaur from the Mesozoic!
Make a model of crinoids at your breakfast table!
Crinoids, also known as sea lilies, are aquatic invertebrates that live their lives attached to the seafloor, filtering plankton with their feather-like arms. Crinoids were abundant on Earth during the Carboniferous and still live in shallow oceans today! You can make your own model of crinoids with our step-by-step tutorial, which can be downloaded here.
Right: Fossil crinoids in Mississippian-aged limestone sit near a model of crinoids made out of pipe cleaners, o-shaped cereal, and feathers. The feathers represent the filter-feeding arms of these aquatic invertebrates that have existed on Earth for hundreds of millions of years.
Fun with mnemonics!
One way to remember the periods of the Phanerozoic Era is to create your own mnemonic device, which is the use of different words in a phrase to help you remember the order of something else. Instead of trying to remember ‘Cambrian, Ordovician, Silurian, Devonian, Mississippian, Pennsylvanian, Permian, Triassic, Jurassic, Cretaceous, Tertiary, Quaternary’, you can make a phrase with easier words. For example, if you hear the word “Jurassic” you can more easily figure out that it’s older than the Quaternary, but not as old as the Cambrian Period. Make sure to not include any extra words. You can always look up the actual dates when you need to. The current Divisions of the Geologic Time Scale can be found here, and you can download a bookmark of the Geologic Time Scale here.
Although we didn’t make these mnemonics up, we learned them a very long time ago and they are stuck in our brains forever:
Want more help understanding deep time?
A two-page PDF introducing the concept of big numbers and geologic time can be downloaded here.
Many science museums across the globe feature fossils and geologic time. Here are few examples (external links): The Smithsonian National Museum of Natural History’s Deep Time exhibit in Washington, DC, the Field Museum’s Griffin Halls Evolving Planet and Sue the T-Rex exhibit in Chicago, IL, the Museum of the Rockies’ Siebel Dinosaur Complex in Bozeman, MT, and the American Museum of Natural History in New York, NY.
Thank you for exploring the USGS Trek Through Time!
We will add more educational resources as they become available,
Please bookmark this page and come back again!