Approximately 300 million years ago, when trees died, they didn’t rot. It took 60 million years for bacteria to evolve to be able to decompose wood. Those piles of non-decomposed heavy wood would eventually compress those trees into peat and then, over time, into coal.
2. Mitochondria are believed to be evolved from specialized bacteria that merged with our cell’s cytoplasm 1.5 billion years ago. This explains why it contains its own DNA.
3. All humanity has a common (8000x) grandmother. An African woman who lived 200,000 years ago is the common maternal ancestor of all humans alive today.
4. 358 million years ago Earth was in the Carboniferous period. During that age oxygen levels were 15% higher than today thanks to the abundance of plant life, which meant scorpions were the size of dogs, a caterpillar was the size of an anaconda and dragonflies were the size of eagles.
5. There were four mass extinction events before the one that killed the dinosaurs. The most severe killed a staggering 97% of all species. All life on Earth today is descended from the 3% that survived.
The Earth has another continent called Zealandia. The entire continent sank after breaking away from Australia around 65-80 million years ago.
7. A Neanderthal who is now named “Shanidar 1” was buried approximately 45,000 to 35,000 years ago. Despite several injuries and disabilities from early in his life that would have made it impossible to survive on his own, he lived to relatively old age (40 to 50) with the help of others.
8. 400 million years ago, before trees took over, Earth was covered in 24-foot mushrooms called prototaxites.
9. Our genes show that we all share a male ancestor who is called Y-Chromosomal Adam. He lived approximately 208,300 years ago.
10. More than 4 billion years ago, Earth was hit by several objects larger than 600 miles that could vaporize the oceans and sterilize the surface yet bacterial life survived deep underground and each time recolonized the planet.
11Natural nuclear reactor
About 1.7 billion years ago, there was a natural nuclear reactor that ran for a few hundred thousand years. The existence of this phenomenon was discovered in 1972 at Oklo in Gabon in Central Africa by French physicist Francis Perrin.
12. The 3.6 million-year-old Laetoli footprints, one of the most important finds concerning human evolution and evidence of upright bipedal walking, was discovered by Paleoanthropologist Andrew Hill when he dove into the ground during the middle of an elephant dung fight with a colleague.
13. A mere 12,000 years ago a species (Homo floresiensis) closely related to modern humans had been living on an Indonesian island. They used fire and rather advanced tools, yet were only about 3 feet tall, weighing around 25kg.
14. During the late Jurassic and Cretaceous periods, the majority of the oceans reefs weren't built by corrals, but rather a group of bivalve clam like mollusks called Rudists.
15. 20 million years ago in North America, the spread of ancient cats led to the extinction of many dog species. There used to about 30 canine species in North America. Only 8 remain.
In the last 5 millennia, genetic change in humans has occurred at a rate roughly 100 times higher than any other period of human evolution. Humans today are more genetically different from humans living 5,000 years ago than these people were from humans living 40,000 years ago.
17. 49 million years ago, a giant bloom of floating plants (Azolla) in the Arctic Ocean tipped the Earth's climate from very hot to very cold.
18. Blond hair in humans developed only 11,000 years ago as an evolutionary response to the lack of sunlight in Northern Europe to enable more Vitamin-D synthesis.
19. Pangaea was not the first supercontinent. That honor goes to the billion-year-old landmass known as Rodinia. The continents routinely split apart and come back together in a process known as the supercontinent cycle.
20. Around 70,000 years ago the Volcano Toba in Indonesia erupted and covered the earth with so much ash the sun was dimmed for 6 years. The population of early humans neared extinction and some studies indicate there were as few as 40 breeding pairs.
The Cambrian Explosion might be explained by rising sea levels 540 million years ago which resulted in three times as much calcium being dissolved into the sea. Life forms had to create shells, bones and other hard tissues in response leading to the diversity of life we see today.
22. During the Cretaceous period (145 - 100 million years ago), Earth's climate was so warm that there were no polar ice caps, and forests probably extended all the way to the South Pole. Local plants and dinosaurs evolved to live in continuous sunlight in the summer and darkness in the winter.
23. Australopithecus, anatomically similar to modern humans, co-existed with Megalodon, the biggest shark species that ever lived.
24. Ancient human ancestor Homo erectus ate cooked food as long ago as 1.9 million years.
25. The Earth is currently and has been in an ice age for over 30 million years, the Late Cenozoic Ice Age.