The Quaternary Period began 1.8 million years ago with an ice age. Scientists refer to the era as the Age of Humans, the time was when hominids gained a foothold on earth. All of the plants and animals that we see today are part of the Quaternary Period; however, there are also extinct animals and plants that lived on the earth during its early stages.
The Two Epochs
The Quaternary Period can be divided into two major epochs; the “Pleistocene” and the “Holocene.” The Pleistocene epoch started 1.8 million years ago and ended around 11,000 years ago, while the Holocene started 11,000 years ago and still continues today. These two epochs have two major differences: geography and climate. Since these two major characteristics play a major role in supporting flora and fauna, these two epochs have unique animals and plants. The Pleistocene epoch is characterized by the series of ice ages that occurred during its reign, while the Holocene epoch has a more stable climate.
Plants during the Quaternary Period
Even though there are major climatic differences between the Pleistocene and the Holocene epoch, much of the plant life didn’t change. The Pleistocene era had two major climate conditions: the glacial and the interglacial. During the glacial period, most of the land was covered by ice, and vegetation was mostly tundra which included mosses, sedges, shrubs, lichens and low-lying grasses; however.During interglacial periods, or the time when most of the soil was not covered by ice, woodlands and coniferous forests existed. The emergence of tropical rainforests occurred during the start of the Holocene. This habitat allowed many animals and plants to thrive and evolve. Coniferous and deciduous forests thrived during this period, as well as savannas, where herbivores grazed and flourished.
Animals of the Pleistocene Epoch
Megafauna, or large mammals, thrived during the Pleistocene period. Animals, such as woolly mammoths, mastodons, true horses, saber-toothed tigers, cave bears and giant deer, are some of the well known giant mammals during the Pleistocene epoch. There are two major theories why these animals became extinct: “over-chill” and “over-kill.” Scientists who believe in the over-chill theory say that all the large animals disappeared because they couldn’t keep up with the climate changes, while scientists who believe in the over-kill theory believe that hominids, our ancestors, hunted down most of these animals, resulting in their extinction.
Animals of the Holocene Epoch
Most of the animals we see today are descendants of animals during the Pleistocene period. The elephants, tigers and horses we see today share genetic relationships to their larger counterparts that existed during the Pleistocene. Modern plants and animals also become extinct, but these extinctions mostly happen because of human actions, like poaching and deforestation. The rise in temperature and the stability of the climate also allow large tropical and coniferous forests to thrive, turning the earth into a perfect habitat for land animals such as mammals, reptiles, amphibians and birds.