Megafauna
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Megafauna are large animals of any particular region or time. Generally, they are defined as animals that weigh over 500 kg to 1 tonne: i.e., any animal larger than the largest widespread domestic animal, the domestic bull. Some authors use much lower thresholds, even as low as 50 kg (making humans a megafauna species), but they are not widely accepted. The term is also used to refer to particular groups of large animals, both to extant species and, more often, those that have become extinct in geologically recent times.
Megafauna animals are generally K-strategists, with great longevity, slow population growth rates, low death rates, and few or no natural predators capable of killing adults. These characteristics make megafauna highly vulnerable to human exploitation. Many species of megafauna have become extinct within the last million years, and, although some biologists dispute it, human hunting is often cited as the cause.
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Usage
The sense in which the term is used is usually apparent from the context:
- A particular group of large, extinct animals. For example, American megafauna, meaning "the various species of large American mammal that became extinct about 13,000 years ago".
- Any group of large animals. For example, South American megafauna, meaning "all large animals in South America today".
Extinction
The extinction of the Megafauna have two major hypotheses. The first cites human intervention, noting that the time of human appearances on the various continents was the time that they became extinct.
The second is that climate changes caused them to die out.
Charismatic megafauna
The term charismatic megafauna refers to animals that have widespread popular appeal. Examples include the Giant Panda, the Indian Elephant, and the Blue Whale.
Charismatic megafauna often garner a disproportionate level of public concern. Environmental activists are aware of this effect and use the extra leverage provided by a charismatic species to achieve more subtle and far-reaching goals. By directing public attention to the plight of the Giant Panda, for example, the environmental movement can raise support not just for the protection of the panda, but for the entire ecosystem on which it depends.
Megafauna by continent
"†" denotes extinct megafauna
- African megafauna
- African Buffalo
- African Elephant
- Forest Elephant
- Hippopotamus
- Black Rhinoceros
- White Rhinoceros
- Giraffe
- Deinotherium †
- Dinofelis †
- Eurasian megafauna
- Aurochs †
- Andrewsarchus †
- Cave Bear †
- Cave lion †
- Deinotherium †
- Dinofelis †
- Entelodont †
- Giant Unicorn †
- Indian Elephant
- Indricotherium †
- Irish Elk † (or Irish giant deer)
- Mammoth †
- Indian Rhinoceros
- Javan Rhinoceros
- Sumatran Rhinoceros
- Woolly Rhinoceros †
- Stegodon †
- Wisent
- Australian megafauna
See also: Australian megafauna
- North American megafauna
- Ice Age Camel † (Camelops herternus)
- American Lion † (Panthera leo atrox)
- Ancient Bison † (Bison antiquus)
- American Mammoth † (Mammuthus columbi)
- Equus † (Equus scotti)
- Giant Beaver † (Castoroides ohioensis)
- Giant Sloth † (Eremotherium rusconii)
- Mastodon †
- Megatherium †
- Saber-toothed Cat † (Smilodon fatalis)
- Short-faced Bear † (Arctodus simus)
- Smilodon †
- Dinofelis †
- Central & South American megafauna
- Glyptodon †
- Megatherium †
- Palaeolama mirifica † (an extinct Llama)
- Litoptern †
- Tapius veroensis † (an extinct Tapir)
- Island megafauna
- Ocean megafauna
- Most whales
- Walrus
- Elephant Seal
- Steller's Sea Cow †
- Basilosaurus †
- Dugong
- Manatee
- Bluefin Tuna
- Marlin
- Basking Shark
- Whale Shark
- Giant Squid
See also
es:Megafauna fr:Mégafaune it:Megafauna nl:Megafauna fi:Megafauna sv:Megafauna