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The geological epoch is a division of time based on the types of rocks, plants, and animals found in different locations. Land plants that generate naked seeds are known as gymnosperms. Gymnosperm evolution indicates the beginning of seed plants rather than spores.

• Seedless and non-vascular plants such as horsetails, ferns, and other non-vascular plants dominated the Carboniferous epoch.
• Many marine creatures lived during the Permian epoch, which is now extinct. During this time, no Gymnosperm was discovered.
• Between the Oligocene and Paleocene epochs is the Eocene. It is distinguished by the appearance of many species of fauna found in today's world.

Gymnosperms are thought to have originally appeared around 319 million years ago, during the Pennsylvanian epoch. Progymnosperms, the earliest naked seed plants, appeared about 380 million years ago and were followed by gymnosperms.

Progymnosperms dominated the late Devonian woods, including the extinct Archaeopteris (not to be confused with the ancient bird Archaeopteryx). The real gymnosperms dominated the landscape during the early (Triassic, c. 240 MYA) and middle (Jurassic, c. 205 MYA) Mesozoic eras.