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Timeline of evolution
This timeline of the evolution of life outlines the major events in the development of life on the planet Earth. Dates given are estimates based on scientific evidence.
In biology, evolution is the process by which populations of organisms acquire and pass on novel traits from generation to generation. Its occurrence over large stretches of time explains the origin of new species and ultimately the vast diversity of the biological world. Contemporary species are related to each other through common descent, products of evolution and speciation over billions of years. The basic timeline is a 4600 million year old Earth with: 4000 my (million years) of simple cells; 3000 my of photosynthesis; 2000 my of complex cells; 1000 my of multicellular life; 600 my of simple animals; 500 my of fish and proto-amphibians; 475 my of land plants; 400 my of insects and seeds; 360 my of amphibians; 300 my of reptiles; 200 my of mammals; 150 my of birds; 100 my of flowers; and 65 my since the non-avian dinosaurs died out.
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Plants & Animals News
July 19, 2026
July 18, 2026 A catastrophic asteroid breakup may have triggered a huge wave of impacts across the inner solar system about 800 million years ago. The debris was launched from near a gravitational gateway controlled by Jupiter, sending fragments toward Earth, the ...
July 17, 2026 A major DNA study has rewritten the koala's evolutionary story, revealing that the species suffered a dramatic population collapse about 100,000 years ago, long before humans arrived in Australia. By calculating the koala's mutation rate for the ...
July 15, 2026 An unusual leopard gecko that naturally develops aggressive tumors may become an important new model for cancer research. Scientists found its tumors share key genetic changes with human cancers, offering a rare opportunity to study the disease as ...
July 14, 2026 A deadly fungus has wiped out amphibian populations around the globe, yet some mysteriously recover. Researchers discovered that survivors develop powerful immune defenses while they are still tadpoles, giving them a head start before the fungus can ...
July 14, 2026 A major review found that people who consumed the most chili peppers had a substantially higher risk of esophageal cancer, though the evidence was less clear for stomach and colorectal cancers. Researchers emphasize that the findings show an ...
July 14, 2026 The world's longest-running soil warming experiment has revealed an unexpected climate concern. After nearly four decades, researchers found that warming can cause microbes to break down stable soil carbon that scientists once believed was largely ...
July 12, 2026 Scientists discovered that extreme deep-sea pressure squeezes valuable nutrients out of sinking organic particles, providing an unexpected food source for ocean microbes. The finding could rewrite our understanding of both deep-ocean ecosystems and ...
July 12, 2026 Why do beaches today have seashells from clams and snails instead of brachiopods? A new study suggests the answer lies in Earth's greatest mass extinction, when warming oceans and falling oxygen levels wiped out animals that couldn't adapt. Species ...
July 11, 2026 Two striking Asian praying mantis species that have rapidly spread across Europe have now been officially classified as invasive, raising new concerns about their impact on native wildlife. Boosted by climate change and urban environments, these ...
July 10, 2026 A next-generation pesticide designed to kill crop pests may also be interfering with the reproductive health of bumblebees. Researchers discovered that low-dose exposure to sulfoxaflor changed gene activity, especially in tissues involved in ...
July 9, 2026 A new study debunks the long-standing claim that baby rattlesnakes are more dangerous than adults. Researchers found that young rattlesnakes can control their venom just like adults, while adult snakes usually inject much more venom and cause more ...
July 9, 2026 Oak trees keep absorbing carbon dioxide long after their annual growth has ended, revealing that photosynthesis and wood production are not as closely linked as scientists once believed. The finding could reshape forecasts of how much carbon forests ...
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July 19, 2026 Fossils from Queensland suggest a newly recognized marsupial order may have survived in Australia for around 35 million years, rewriting part of the story of how the continent's unique mammals ...
July 16, 2026 An ancient sea worm may hold the secret to a whole new category of natural materials. Its jaws combine proteins and metal ions in a way that gives ...
July 15, 2026 Humans are often described as the planet's ultimate "super-predator," but wild animals do not fear every human the same way. After analyzing three decades of research, scientists found that animals ...
July 14, 2026 Chimpanzees showed a remarkable attraction to crystals, choosing them over ordinary stones and studying them with intense curiosity. The results ...
July 14, 2026 A fossilized Edmontosaurus skull with a Tyrannosaurus tooth still embedded in its face has given scientists rare evidence of a dramatic predator-prey encounter. The discovery suggests the giant ...
July 12, 2026 A new study suggests spacecraft exhaust could quickly contaminate the moon's most scientifically valuable regions, potentially masking ancient clues about how life began on Earth. Researchers say ...
July 12, 2026 Citizen scientists have helped researchers solve a long-standing mystery about how parental care evolved in harvestmen. Using photos and observations from iNaturalist, scientists more than doubled ...
July 10, 2026 Scientists have discovered a previously unknown fossil goose that challenges a decades-old theory about the evolution of New Zealand's birds. The find suggests the country's giant flightless geese ...
July 9, 2026 A newly discovered Happy-Face spider in the Himalayas closely resembles Hawaii's iconic species but evolved independently, according to DNA evidence. Its mysterious smile-like markings, many color ...
July 8, 2026 For the first time, researchers have filmed the elusive goblin shark alive in the deep ocean where it naturally lives. The remarkable sightings greatly expand the shark's known range and depth, ...