Summary
Highlights
Biomes are collections of living organisms adapted to specific climates. The video introduces the five main types (tundra, forest, grassland, desert, and aquatic) and notes Holdridge's matrix for further specification. It will discuss 11 types and their associated animals.
Tundra covers about 10% of Earth's landmass, characterized by extremely low temperatures and precipitation, preventing tree growth. Three types exist: Arctic, Antarctic (latitude-based), and Alpine (altitude-based). Arctic tundra features permafrost and supports animals like muskox, reindeer, arctic foxes, wolves, and polar bears. Antarctic tundra hosts seals and penguins. Alpine tundra, found in mountainous regions, has a milder summer, richer soil, and animals like mountain goats, snow leopards, and golden eagles.
Forest biomes, covering 40% of the Earth, are defined by the presence of trees and are categorized as Boreal, Temperate, and Tropical forests based on latitude. Boreal forests (Taiga) have coniferous trees and support moose, wood bison, Siberian tigers, lynx, brown bears, beavers, and stoats. Temperate forests have deciduous trees with animals like various deer species, cougars, black bears, badgers, squirrels, red pandas, and koalas. Tropical forests (Rainforests) are highly biodiverse, found near the equator, and are home to tigers, jaguars, anacondas, primates (chimpanzees, gorillas), anteaters, sloths, tapirs, parrots, and diverse reptiles and insects.
Grasslands are open, fertile plains covering about 25% of the world's landmass, split into tropical and temperate types. Tropical grasslands (Savannah) are found in Africa, South America, Australia, and Mexico, with predators like lions, cheetahs, hyenas, and African wild dogs, and herbivores like zebra, wildebeest, elephants, and rhinos. Temperate grasslands (Steppe, Prairie, Pampas, Veld) have cold nights and winters, supporting coyotes, foxes, pampas cats, bison, wild horses, gazelles, and smaller mammals like prairie dogs and black-footed ferrets. Both grasslands host diverse bird and insect species.
Deserts comprise about 25% of Earth's landmass, marked by low precipitation and high temperatures. Animals have evolved for water scarcity, often being nocturnal. Iconic desert animals include camels, addax antelopes, mule deer, cougars, bobcats, fennec foxes, kangaroo rats, gerbils, and meerkats. Reptiles and invertebrates like rattlesnakes, scorpions, and various spiders thrive here. Birds such as roadrunners and burrowing owls are also adapted to this arid environment, along with many insect species, including viceroy butterflies known for mimicry.
Aquatic biomes cover 71% of Earth's surface and are divided into marine (saltwater) and freshwater types. The marine biome, the largest, includes oceans, coral reefs, and estuaries. It hosts massive animals like whales (including apex predator orcas), manatees, seals, sea lions, walruses, sea turtles, and saltwater crocodiles. Fish are diverse, ranging from cartilaginous sharks and rays to numerous bony fish. Invertebrates like octopuses and coral are also prevalent. Freshwater biomes, characterized by low salt levels, include ponds, lakes, streams, rivers, and wetlands. They support fish like trout, pike, bass, piranhas, and migratory salmon. Many birds (ducks, swans, kingfishers) and mammals (capybaras, otters, beavers) thrive here, as do amphibians like frogs and salamanders, reptiles like caiman and terrapins, and insects like dragonflies and water striders.