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The controversial Toba catastrophe theory, presented in the late 1990s to early 2000s, suggested that a bottleneck of the human population occurred approximately 75,000 years ago, proposing that the human population was reduced to perhaps 10,000–30,000 individuals [14] when the Toba supervolcano in Indonesia erupted and triggered a major ...
Earlier genetic analysis of Alu sequences across the entire human genome has shown that the effective human population size was less than 26,000 at 1.2 million years ago; possible explanations for the low population size of human ancestors may include repeated population crashes or periodic replacement events from competing Homo subspecies. [88]
The table starts counting approximately 10,000 years before present, or around 8,000 BC, during the middle Greenlandian, about 1,700 years after the end of the Younger Dryas and 1,800 years before the 8.2-kiloyear event. From the beginning of the early modern period until the 20th century, world population has been characterized by a rapid growth.
how the earth was made premiered as a 90-minute documentary special, narrated by Edward Herrmann, that aired on the History Channel on December 16, 2007, and focused on the geological history of Earth. The History Channel released the original documentary film to Region 1 DVD through Warner Home Video on April 15, 2008, and to Blu-ray through A ...
The earliest evidence for life on Earth includes: 3.8 billion-year-old biogenic hematite in a banded iron formation of the Nuvvuagittuq Greenstone Belt in Canada; [30] graphite in 3.7 billion-year-old metasedimentary rocks in western Greenland; [31] and microbial mat fossils in 3.48 billion-year-old sandstone in Western Australia.
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Earth formed in this manner about 4.54 billion years ago (with an uncertainty of 1%) [25] [26] [4] and was largely completed within 10–20 million years. [27] In June 2023, scientists reported evidence that the planet Earth may have formed in just three million years, much faster than the 10−100 million years thought earlier.
It is estimated by J. Lawrence Angel [15] that the average life span of hominids on the African savanna between 4,000,000 and 200,000 years ago was 20 years. This means that the population would be completely renewed about five times per century, [ citation needed ] assuming that infant mortality has already been accounted for [ clarification ...