Amazon rainforest
The name Amazon rainforest arises from a war fought by Francisco de Orellana with the Tapuyas and other tribes in 1542. Women of the tribe fought alongside men, as was their custom during that conflict. Orellana derived the name Amazonas from the Amazons of Greek mythology, described by Herodotus and Diodorus. This historical naming event occurred over four centuries ago when European explorers first mapped the region's vast waterways.
Archaeological evidence from an excavation at Caverna da Pedra Pintada shows human inhabitants settled in the Amazon region at least 11,200 years ago. Late-prehistoric settlements along the forest periphery existed by AD 1250, inducing alterations in forest cover. Some 5 million people may have lived in the Amazon region in AD 1500, divided between dense coastal settlements like Marajó and inland dwellers. The Upano Valley sites in present-day eastern Ecuador predate all known complex Amazonian societies. Ondemar Dias discovered geoglyphs on deforested land dating between AD 1, 1250 in 1977. Alceu Ranzi furthered these discoveries after flying over Acre. Michael Heckenberger and colleagues found remains of large settlements including roads, bridges and plazas in the Xingu tribe region in 2003.
The rainforest likely formed during the Eocene era spanning from 56 million years to 33.9 million years ago. It appeared following a global reduction of tropical temperatures when the Atlantic Ocean widened sufficiently to provide warm, moist climate to the Amazon basin. The rainforest has been in existence for at least 55 million years. During the Oligocene, the rainforest spanned a relatively narrow band before expanding again during the Middle Miocene. Within the last 5, 10 million years, accumulating water broke through the Purus Arch, joining easterly flow toward the Atlantic. More than 56% of dust fertilizing the Amazon comes from the Bodélé depression in Northern Chad in the Sahara desert. NASA's CALIPSO satellite measures an average of 182 million tons of dust windblown out of the Sahara each year, with 15% falling over the Amazon basin.
One in ten known species in the world lives in the Amazon rainforest, constituting the largest collection of living plants and animal species globally. The region is home to about 2.5 million insect species, tens of thousands of plants, and some 2,000 birds and mammals. At least 40,000 plant species, 2,200 fishes, 1,294 birds, 427 mammals, 428 amphibians, and 378 reptiles have been scientifically classified in the region. A 2001 study found one quarter square kilometer of Ecuadorian rainforest supports more than 1,100 tree species. Each hectare contains around 1 billion invertebrates. Among the largest predatory creatures are the black caiman, jaguar, cougar, and anaconda. Electric eels can produce shocks that stun or kill humans while piranha bite and injure people.
In 2022, about 20% of the Amazon rainforest has already been deforested and a further 6% was highly degraded. Between 1991 and 2000, total forest lost rose significantly with most becoming pasture for cattle. Seventy percent of formerly forested land and 91% of land deforested since 1970 have been used for livestock pasture. Deforestation reached a 15 year high in 2021 under President Jair Bolsonaro's administration. There were 72,843 fires in Brazil in 2019, with more than half within the Amazon region. In August 2019 there was a record number of fires. Deforestation in the Brazilian Amazon rose more than 88% in June 2019 compared to the same month in 2018. Ninety-four percent of the territory is affected by oil fields while 17% is affected by mining operations.
A study published in Nature Communications in October 2020 found that about 40% of the Amazon rainforest is at risk of becoming a savanna-like ecosystem due to reduced rainfall. Research from 2025 using hundreds of climate-model simulations says even passing 1.5C of global warming temporarily would trigger significant risk of Amazon forest dieback. A 2009 study found that a 4°C rise in global temperatures by 2100 would kill 85% of the Amazon rainforest while a temperature rise of 3°C would kill some 75%. In 2005, parts of the basin experienced the worst drought in one hundred years. During 2005 instead 5 gigatons were released and in 2010 8 gigatons were released as carbon dioxide. Half of the rainfall in the Amazon area is produced by the forests themselves.
In April 2019, the Ecuadorian court stopped oil exploration activities in part of the Amazon rainforest. In July 2019, the Ecuadorian court forbade the government to sell territory with forests to oil companies. From 2002 to 2006, conserved land in the Amazon almost tripled and deforestation rates dropped up to 60%. About have been put onto some sort of conservation, adding up to a current amount of . In September 2019, the US and Brazil agreed to promote private-sector development with a $100m biodiversity conservation fund led by the private sector. In January 2024 published data showed a 50% decline in deforestation rate in the Amazon rainforest during 2023 compared to 2022. Members of the Trio Tribe use handheld GPS devices and programs like Google Earth to map out their ancestral lands in southern Suriname.
Common questions
Who named the Amazon rainforest and when did this happen?
Francisco de Orellana named the Amazon rainforest in 1542 after fighting with the Tapuyas tribe. He derived the name Amazonas from the Amazons of Greek mythology described by Herodotus and Diodorus.
When was the Amazon rainforest formed and how long has it existed?
The Amazon rainforest likely formed during the Eocene era spanning from 56 million years to 33.9 million years ago. It has been in existence for at least 55 million years.
How many species live in the Amazon rainforest today?
One in ten known species in the world lives in the Amazon rainforest including about 2.5 million insect species and tens of thousands of plants. At least 40,000 plant species, 2,200 fishes, 1,294 birds, 427 mammals, 428 amphibians, and 378 reptiles have been scientifically classified in the region.
What percentage of the Amazon rainforest is deforested as of 2022?
In 2022, about 20% of the Amazon rainforest has already been deforested and a further 6% was highly degraded. Seventy percent of formerly forested land and 91% of land deforested since 1970 have been used for livestock pasture.
When did the Ecuadorian court stop oil exploration activities in the Amazon rainforest?
In April 2019, the Ecuadorian court stopped oil exploration activities in part of the Amazon rainforest. In July 2019, the Ecuadorian court forbade the government to sell territory with forests to oil companies.