Carboniferous

The Carboniferous Period was marked by a warm, humid global climate and widespread lowland swamps, especially near the equator. Much of the Earth’s land was assembling into the supercontinent Pangaea, formed by the collision of major landmasses including Laurussia and Gondwana. Extensive tropical wetlands led to the accumulation of vast plant material, which later became the coal deposits that give the period its name. At the same time, southern regions experienced significant glaciation as Gondwana drifted over the South Pole. Major mountain-building events, such as the Variscan orogeny and Alleghanian orogeny, reshaped continents and contributed to the formation of large mountain belts.

Biologically, the Carboniferous saw major evolutionary advances. Dense forests of lycopsids, ferns, and horsetails dominated landscapes, driving high oxygen levels that may have exceeded 30%, enabling giant arthropods like Meganeura. Crucially, this period witnessed the diversification of early amniotes—the first vertebrates to reproduce on land without water—leading to the split between reptile and mammal lineages. Amphibians flourished in swampy environments, while marine ecosystems continued to expand with abundant crinoids, brachiopods, and sharks. These developments laid key foundations for terrestrial ecosystems and vertebrate evolution in the later Permian and beyond.