Pleistocene (Cenozoic period, Tertiary era)

Kenya. KNM-ER 1808 is the paleonanthropological code name for a woman who lived 1.7 million years ago, whose skeleton was discovered by Kenyan anthropologist Kamoya Kimeu in 1974 at the Koobi Fora archaeological site in Kenya. She is a female Homo erectus with bone deformities in her legs, due to hypervitaminosis A, which prevented her from moving during the last months of her life. This means she was cared for and helped for several months. This is the first fossil evidence of the very human emotion of compassion.

Appearance of Homo Abilis in Sub-Saharan Africa

The first stone tools were used to open the bones of animal carcasses and eat the marrow. The genus Homo is therefore low in the predatory hierarchy, able to access the carcass only after large predators, hyenas, and vultures.

First ice in the Arctic: it is formed thanks to a change in the inclination of the Earth’s axis and a simultaneous increase in humidity (which causes intense snowfalls) due to the stratification (caused by the reduction of marine recirculation) of the waters of the Pacific

The appearance of a supernova in the sky causes serious consequences, first of all probably a notable reduction of the ozone layer, especially at latitudes above 30 degrees.

Lucy (Australopithecus Afarensis) lives in Ethiopia

First hominids: Ardipithecus Ramidus in Ethiopia

Last gene exchange between the chimpanzee race and that of hominids

Following the upheaval of the Northeastern Andes, which interrupted the connection between the internal sea in the current Amazon rainforest and the Caribbean Sea, the Amazon River was born, draining the remaining lakes within.

Goats evolve in Europe and Africa.

When the African and European continental plates collided, they not only raised new mountains in central Europe, but also created the largest lake the world has ever known. This vast body of water, the Paratethys Sea, is home to species found nowhere else, including the world’s smallest whales.

The upheaval of the Northeastern Andes severed the connection between the inland sea in the current Amazon rainforest and the Caribbean Sea; this triggered the birth of the Amazon River.

The Andes rise

Thirty million years ago, one of the first hominid species, Nsungwepithecus, developed in Europe. In Africa (Tanzania), the first hominid species (Rukwapithecus, which would give rise to orangutans, gorillas, chimpanzees, and humans) developed only five million years later. Hominids in Africa failed to compete with other apes, but in Africa, Nacholapithecus, 13 million years ago, managed to cross a temporary land bridge to Europe. Then, 11 million years ago, other ape species also arrived in Europe from Africa, while Hispanopithecus evolved in Europe, followed by Graecopithecus freybergi, 7 million years ago. The latter was discovered after a reanalysis in May 2017 of artifacts found in Athens by Wehrmacht soldiers while building a swimming pool in a former underground shelter in 1944. The remains are dated to 7,175,000 years ago. Numerous fossilized human traces dating back 5.7 million years were also found on Crete, but shortly thereafter, hominids became extinct in Europe and likely returned to Africa, perhaps due to the Messinian Salinity Crisis (caused by Africa’s closure of Gibraltar), which completely dried out the Mediterranean Sea between 5.9 and 5.3 million years ago, rendering much of the surrounding area uninhabitable. During the Messinian Salinity Crisis, salt deposits 1.5 km thick were deposited on the Mediterranean Sea floor (a million cubic kilometers of salt was locked there, changing the salinity of the rest of the world’s seas). Temperatures on these deposits reached 80°C, and the Nile and other major rivers failed, by a factor of ten, to contribute enough water to maintain the Mediterranean Sea. Then, 5.3 million years ago, Gibraltar reopened, and the Atlantic Ocean flooded the Mediterranean (Langelian Flood) in just a century (the level rose up to 10 meters per day).

The first honeybees, or Apis, evolved. They are a type of vegetarian wasp.

Australia breaks away from Antarctica

Europe. A dramatic change: the Great Cut. The Eocene, with its tropical climate, ends and the Oligocene, with its continental and Arctic climate, begins. The cause appears to be the detachment of South America from West Antarctica, which drastically altered ocean currents. Temperatures in England drop by 6-8°C, and by an average of 10°C in summer.

First whales. They evolved from what would later become dolphins, a species that (re)entered the seas about 49 million years ago.

Between Greenland and Norway rises an island 500 km long north-south and 15 km wide, of marshy nature, covered with conifers and ferns. No mammals have been found, which probably never arrived here; it now lies 2 km beneath the waves in the middle of the Atlantic: the Hovgaard Ridge.

Mass extinction of living species

Rodents and monkeys arrived in South America, likely from neighboring (but not adjacent) Africa. How they got there is still unclear, but they probably migrated gradually from one island to another.

branching off between the species that would later become dolphins, in the sea, and the one that remained on land, which would give rise to, for example, hippos. 15 million years later, whales would also branch off.

Early Eocene. Palm trees grow in the Antarctic, crocodiles splash around in the shallows of England. The climate is significantly warmer than today. This shows that a very warm climate doesn’t necessarily mean problems for life. On the contrary, it could mean more species living in the long term (though not necessarily including Homo sapiens). Nearly every species on the planet today is adapted to the cold, due to the repeated ice ages over the past million years.

Cava della Pesciara, Verona, Italy. An exceptional fossil deposit forms here, demonstrating how modern corals evolved in the Tethys Sea, between Europe and Africa.

At the end of the Paleocene, Uintatherium, a huge rhinoceros-like mammal with six rounded horns, thrived.

First Cetaceans (ancestors of marine mammals)

The North Atlantic opens

Paleocene-Eocene Thermal Maximum (PETM): At the North Pole, summer temperatures reached 23 degrees Celsius, and ocean levels were 70 meters higher than today. Plankton shells disappeared from the mud on the seafloor, which turned from white to red. During the PETM, a mass of carbon of as yet unknown origin, equivalent to the contents of all present-day coal, oil, and gas deposits, flooded the atmosphere; temperatures rose by an average of 5°C. Seas and forests took more than 150,000 years to reabsorb it. Carbon dioxide also spread into the seas, acidifying them and dissolving shells. Ocean currents changed dramatically, the seas became acidic, and single-celled organisms in the deep ocean became extinct en masse. The source of the abnormally high carbon emission into the atmosphere may have been the release of enormous bubbles of methane and natural gas from the ocean floor, the craters of which are still visible. Note that all this was triggered by a smaller amount of greenhouse gases than humanity is currently causing.

Peak greenhouse effect: This is called the Paleocene-Eocene Thermal Maximum (PETM). A mass of carbon of as yet unknown origin, equivalent to the content of all present-day coal, oil, and gas deposits, invades the atmosphere; the temperature increases by an average of 5°C.

Deccan Traps Episode (Southern India): Massive series of eruptions in a short period of less than a million years, the episode occurs due to the outcrop of a mantle convective cell, which expels enough lava to cover the entire territory of the USA with a thickness greater than 1 km

KT + 5 minutes. The tsunami, with waves 300 meters high, reaches the coast. It will cover all of present-day Texas, reaching as far as Oklahoma.

KT + 115 seconds. The 35km-high water column from the Chicxulub meteorite triggers a tsunami with waves 300m high.

KT Episode. The Chicxulub meteorite impact causes 20-meter waves and an earthquake measuring 11-12 on the Richter scale.