Triassic–Jurassic Extinction: Volcanoes Open the Age of Dinosaurs
Reference date: ~201 Million Years Ago
Cause: Massive Volcanic Eruptions
Description:
As Pangea began to break apart, enormous volcanic eruptions tied to the Central Atlantic Magmatic Province released greenhouse gases and disrupted oceans. Many competitors vanished, while dinosaurs survived and soon rose to dominate the Jurassic world.
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Latest 4 Research Tidbits
It’s time to explore the 4 latest tidbits.
A tidbit is a well-nuanced quote, story, or FAQ within science, philosophy, critical thinking, or history. First up.
1.
A Science Story.
From History:
Subject: Evolution.
~201 Million Years Ago
Cause: Massive Volcanic Eruptions
The Triassic–Jurassic extinction cleared ecological space for dinosaurs to become the dominant land animals of the Jurassic.
Put simply.
About 201 million years ago, massive volcanic eruptions disrupted climate and oceans as Pangea began to split. Many competitors vanished. Dinosaurs did not just survive the crisis; they inherited the world it left behind.
Now, the details…
That Science Story,
was first published on TST 1 day ago.
The flashcard inspired by it is this.
2.
A Science Story.
From History:
Subject: Evolution.
~372–359 Million Years Ago
Cause: Ocean Anoxia
The Devonian extinction shows that evolution can be reshaped not by one sudden blow, but by a long collapse in ocean health.
Now, to be clear.
Across millions of years, oxygen-poor seas slowly choked marine life during the Devonian crisis. Reefs fell, many species disappeared, and the balance of life shifted. It is a reminder that when oceans lose their breath, evolution changes course.
Now, the details…
The Devonian extinction was not one sudden blow, but a long crisis across millions of years. Many marine species disappeared as oceans became oxygen-poor. The exact cause remains debated, but likely stressors include nutrient runoff, algal blooms, climate shifts, and widespread ocean anoxia.
That Science Story,
was first published on TST 1 day ago.
The flashcard inspired by it is this.
3.
A Science Story.
From History:
Subject: Evolution.
~444 Million Years Ago
Cause: Global Cooling and Falling Seas
The Ordovician–Silurian extinction shows how climate change can reshape evolution by collapsing old ecosystems and opening space for new life.
Stepping back for a moment.
About 444 million years ago, global cooling locked water in ice, sea levels fell, and shallow marine habitats vanished. Most life still lived in the oceans, so the damage was enormous. Yet after the collapse, life reorganized. Evolution did not stop; it changed direction.
Now, the details…
This extinction hit marine life hard, especially organisms living in shallow seas. The leading explanation centers on glaciation over Gondwana, falling sea levels, and disrupted ocean habitats. As seas withdrew, vast marine ecosystems collapsed, clearing space for new evolutionary paths in the Silurian.
That Science Story,
was first published on TST 1 day ago.
The flashcard inspired by it is this.
4.
A Science Story.
From History:
Subject: Evolution.
From 717 million years ago through 635.
Cause: Continental Drift, Falling CO₂
Snowball Earth was a time when our planet may have frozen nearly from pole to pole, testing life and setting the stage for later biological change.
Looked at differently.
During the Cryogenian, Earth endured two immense glaciations that may have covered most or all of the planet in ice. Whether fully frozen or more “slushy,” this deep freeze likely pressured life to adapt, survive in refuges, and helped prepare the world for the later rise of complex multicellular organisms.
Now, the details…
Before Snowball Earth, before about 717 million years ago, Earth was already changing in big ways. The supercontinent Rodinia was breaking apart. Volcanic activity exposed vast stretches of fresh rock, and as that rock weathered, it pulled carbon dioxide from the atmosphere. With less greenhouse warming, the planet became more vulnerable to a runaway freeze. Life was still mostly microbial, along with simple eukaryotes, but the groundwork for later complexity was already quietly taking shape.
Then came the deep freeze. During the Cryogenian, Earth endured two immense glaciations: the Sturtian and the Marinoan. Geological evidence shows ice-related deposits formed at very low latitudes, strongly suggesting that ice reached close to the equator. Some researchers still debate whether Earth became a hard “Snowball” or a softer “Slushball,” but either way, it was one of the most extreme climate crises in the history of our planet.
When the ice finally retreated, Earth entered the Ediacaran world. The post-glacial planet was different. Its oceans, chemistry, and ecosystems had been shaken hard. Many researchers think these brutal Cryogenian conditions, along with the refuges life found during the freeze, helped drive a burst of evolutionary experimentation. Not long after, the fossil record begins to show a wider expansion of multicellular life, making Snowball Earth one of the great turning points in the long story of animals.
That Science Story,
was first published on TST 1 day ago.
The flashcard inspired by it is this.
Front: The common name for the time when Earth was nearly or fully covered in ice.
Back: Snowball Earth (starting about 717 million years ago)..