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Decline in CO2 cooled Earth’s climate over 30 million years ago
earth's climate CO2 greenhouse
2021/8/5
New research demonstrates that a decline in the concentration of atmospheric CO2 played a major role in driving Earth's climate from a warm greenhouse into a cold icehouse world around 34 million year...
Geoscientists reconstruct 6.5 million years of sea level in the Western Mediterranean（图）
Geoscientists reconstruct 6.5 million years sea level Western Mediterranean
2021/2/5
The pressing concern posed by rising sea levels has created a need for scientists to predict how quickly the oceans will rise in coming centuries, researchers say. To gain insight into future ice shee...
Deep sea microbes dormant for 100 million years are hungry and ready to multiply（图）
Deep sea microbes dormant 100 million years hungry ready to multiply
2020/7/31
For decades, scientists have gathered ancient sediment samples from below the seafloor to better understand past climates, plate tectonics and the deep marine ecosystem. In a new study published in...
Volcanic coal-burning in Siberia led to climate change 252 million years ago（图）
Volcanic coal-burning Siberia led climate change 252 million years ago
2020/6/19
A team of researchers led by Arizona State University geoscientist Linda Elkins-Tanton has provided the first direct evidence that extensive coal burning in Siberia was a cause of the Permo-...
Unraveling arthropod genomic diversity over 500 million years of evolution（图）
arthropod genomic diversity 500 million years evolution
2020/2/20
Comparative analyses by scientists at the Swiss Institute of Bioinformatics and other institutions of 76 arthropod species spanning 500 million years of evolution reveal genomic changes that point to ...
Scientists find oldest-known fossilized digestive tract — 550 million years（图）
Scientists oldest-known fossilized digestive tract 550 million years
2020/1/19
A 550-million-year-old fossilized digestive tract found in the Nevada desert could be a key to understanding the early history of animals on Earth.More than a half-billion years ago, life on Earth con...
Mass extinction of land and sea biodiversity 250 million years ago not simultaneous（图）
Mass extinction land sea biodiversity 250 million years ago simultaneous
2019/12/13
Some 250 million years ago, simultaneous mass extinctions of marine and terrestrial life occurred in an event known as the End-Permian. Or so scientists believed.New research led by Colby College geol...
Six million years ago, atmospheric shifts led to increased diversity of grassland mammals（图）
Six million years ago atmospheric shifts grassland mammals
2019/10/30
Six million years ago, grass-eating mammals became more diverse in South America. Shifts in tropical atmospheric circulation known as Hadley circulation led to changes in climate and vegetation, espec...
Crabs, lobsters and shrimp now have a family tree dating 500 million years（图）
Crabs lobsters shrimp family tree dating 500 million years
2019/10/30
Researchers have for the first time traced the roots of crabs, lobsters and shrimp to create the family tree of crustaceans people love to eat.The tree shows the 450-million-year evolution of these 10...
Tectonic collision 50 million years ago led to widespread ocean changes（图）
Tectonic collision 50 million years ago widespread ocean changes
2019/11/22
When the landmass that today is the Indian subcontinent slammed into Asia some 50 million years ago, the collision changed the configuration of the continents and altered global climate.Now a team of ...
Nearly 500 finger and toe bones belonged to tiny primates 45 million years ago（图）
Nearly 500 finger toe bones belonged tiny primates 45 million years ago
2017/11/23
At Northern Illinois University, Dan Gebo opens a cabinet and pulls out a drawer full of thin plastic cases filled with clear gelatin capsules. Inside each numbered capsule is a tiny fossil—some are s...
400 million years of a stable relationship:clues to the molecular basis of balance in AM symbiosis
400 million years stable relationship molecular basis of balance AM symbiosis
2017/4/27
Walking through a grassy field or forest take a moment to consider what lies beneath the surface. A web of plant roots interacts symbiotically with arbuscular mycorrhizal (AM) fungi that extend their ...
Vision,not limbs,led fish onto land 385 million years ago
Vision not limbs led fish onto land 385 million years ago
2017/3/30
EVANSTON - A provocative new Northwestern University and Claremont McKenna, Scripps and Pitzer colleges study suggests it was the power of the eyes and not the limbs that first led our ancient aquatic...
Caribbean bat species need 8 million years to recover from recent extinction waves
Caribbean bat 8 million years recover recent extinction waves
2017/2/15
Find related stories on NSF's Environmental Research and Education and Dimensions of Biodiversityprograms.How long does it take a community of mammals to recover after a wave of species...
Original Dinosaur Claw Sheath Proteins Preserved for 75 Million Years
Original Dinosaur Claw Sheath Proteins Preserved 75 Million Years
2016/11/29
One of the most well-recognized Cretaceous fossils is Citipati osmolskae (MPC-D 100/979), an oviraptorid dinosaur discovered in brooding position on a nest of unhatched eggs. The original description ...