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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...
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-...
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...
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...
Ant Agricultural Revolution Began 30 Million Years Ago in Dry,Desert-like Climate
Ant Agricultural Revolution 30 Million Years Ago in Dry Desert-like Climate
2017/4/27
Millions of years before humans discovered agriculture, vast farming systems were thriving beneath the surface of the Earth. The subterranean farms, which produced various types of fungi, were cultiva...
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...
Robot Helps Study How First Land Animals Moved 360 Million Years Ago
Robot Land Animals Moved 360 Million Years Ago
2016/7/15
When early terrestrial animals began moving about on mud and sand 360 million years ago, the powerful tails they used as fish may have been more important than scientists previously realized. That’s o...
Well-preserved fossils show ostrich relatives lived in North America 50 million years ago
fossils ostrich relatives North America 50 million years ago
2016/7/15
Exceedingly well-preserved bird fossil specimens dating 50 million years represent a new species that is a previously unknown relative of the modern-day ostrich, according to a new paper co-authored b...
Nearby massive star explosion 30 million years ago equaled detonation of 100 million suns
massive star explosion 30 million years ago detonation of 100 million suns
2016/5/6
A giant star that exploded 30 million years ago in a galaxy near Earth had a radius prior to going supernova that was 200 times larger than our sun, according to astrophysicists at Southern Methodist ...
Giant flightless bird wandered the Arctic 50 million years ago
Giant flightless bird Arctic 50 million years ago
2016/2/23
It’s official: There really was a giant, flightless bird with a head the size of a horse’s wandering about in the winter twilight of the high Arctic some 53 million years ago.The confirmation comes fr...
Ants Were Socializing–and Sparring–Nearly 100 Million Years Ago,Rutgers Study Finds
Ants Were Socializing Sparring Rutgers Study
2016/2/23
Like people, ants have often fought over food and territory.But ants began fighting long before humans: at least 99 million years ago, according to Phillip Barden, a fossil insect expert who works in ...
Earliest known fossil of the genus Homo dates to 2.8 to 2.75 million years ago
the genus Homo dates 2.8 2.75 million years ago
2015/3/18
UNIVERSITY PARK, Pa. -- The earliest known record of the genus Homo -- the human genus -- represented by a lower jaw with teeth, recently found in the Afar region of Ethiopia, dates to between 2.8 and...
Tooth Loss in Birds Occurred About 116 Million Years Ago
Tooth Loss in Birds 116 Million Years Ago
2014/12/30
RIVERSIDE, Calif. — The absence of teeth or “edentulism” has evolved on multiple occasions within vertebrates including birds, turtles, and a few groups of mammals such as anteaters, baleen whales and...