What are the Seven Major Biomes?

Biologists have organized all the life on Earth into four levels of complexity and interaction. In this schema, species of organisms live in "communities" where they compete for food and habitat. At the next level, communities interact in an "ecosystem." The ecosystem includes weather and geology of the area in addition to plants and animals. For example a specific forest qualifies as an ecosystem. Then, taken together, those ecosystems that share major characteristics of terrain create a biome. A biome is united by temperature, precipitation, soil type, vegetation, latitude, and elevation. At the most macroscopic level reigns the biosphere of our Earth that contains all the life we know exists in the universe.

Biomes are spread across the Earth's surface. That is, part of the Florida Everglades have more in common with India, in terms of ecosystems, than it does with Georgia right next door. Treating the world as a system of biomes allows biologists to study climate, geology, endangered species, agriculture, and many related subjects. Biomes were formed at different stages of Earth's evolution, depending on the presence of organic matter, water, plate tectonics, and where, in terms of latitude, the terrain lies. Since the Earth is tilted on its axis, and moves around the sun, latitude can tell us how much light hits the surface.

The seven major biomes are divided into six terrestrial (ground) and one aquatic (water) biome. The aquatic biome can be categorized as both marine and freshwater biomes. Sometimes freshwater lakes, rivers, streams, and underground aquifers belong to the surrounding terrestrial biome. The terrestrial biomes are tundra, rainforest, grasslands (also called prairie or steppe), taiga (boreal or coniferous forest), desert, and temperate (deciduous) forest. Some biologists define more than seven major biomes, adding chaparral, mountain, island, or tropical dry forest. Other biomes are further subdivided, such as deep ocean, open ocean, and shallow ocean marine biome, or the hot and cold deserts.

A biome is a large ecological area on the Earth's surface with distinct plant and animal groups adapted to the environment. There are seven major biomes: tropical rainforests, savannas, deserts, grasslands, temperate forests, taigas, and tundras. Each biome has unique climate conditions, flora, and fauna that create diverse ecosystems.

Tropical rainforests are characterized by high rainfall, typically exceeding 200 centimeters annually, and consistent warm temperatures. They boast the highest biodiversity among the biomes, with millions of species. The dense canopy structure, high humidity, and year-round growth period make them vital for global oxygen production and carbon sequestration.

Animals in desert biomes have evolved remarkable adaptations to survive extreme conditions. They often exhibit behaviors like nocturnal activity to avoid daytime heat, and physiological adaptations such as efficient water conservation and temperature regulation. For instance, camels can go for days without water by storing fat in their humps, which is metabolized when needed.

Grasslands, covering about 25% of the world's land area, are crucial for supporting a variety of wildlife and maintaining biodiversity. They act as carbon sinks, storing carbon in their soil, and are important for agriculture, providing grazing lands for livestock and fertile soil for crop production. Grasslands also help regulate the water cycle and prevent soil erosion.

The taiga, or boreal forest, supports a range of mammals like moose, bears, and lynxes, adapted to its cold, long winters and short summers. In contrast, the tundra, with its harsher climate and permafrost, has fewer species, such as reindeer, arctic foxes, and migratory birds, adapted to the extreme cold and limited vegetation.

Temperate forests face numerous environmental threats, including deforestation for agriculture and urban development, which leads to habitat loss and fragmentation. Climate change is altering their weather patterns, affecting species' survival. Pollution and invasive species also pose significant risks, disrupting the natural balance and leading to a decline in native biodiversity.