The earliest modern era is usually known as the time period that began around 26 million years ago and lasted until about 11,700 years ago, when the last Ice Age occurred, when glaciers covered large parts of the planet.
There were at least five of the major ice ages documented in 4.6 billion years since Earth formed and most likely before humans came to the scene about 2.3 million years ago.
What is the earliest modern era?
In the name of Ice Age is the geology of the era that lasted from about 2,580,000 to 11,700 years ago, and extends to the most recent periods of repeated glaciation in the world, the end of the Pleistocene era coincides with the end of the last Ice Age and also with the end of the Stone Age used in archeology .
The Ice Age is the first era of the Quadruple period or the sixth era of the Era of Modern Life Era, and in the ICS timeline the Ice Age is divided into four phases or ages, the Gelassic, Calabria, Chibanian, and the Upper Ice Age, in addition to these international subdivisions, often What is used different regional subdivisions.
Before the change was finally confirmed in 2009 by the International Union of Geological Sciences, the time limits between the ice age and the pre-modern era were considered to be taking place in 1806,000 years before the present (BP), as opposed to currently accepted 2.58 million years ago.
Ice sheets around the world
In the earliest modern era or Pleistocene, the continents had moved to their present locations, at some point during the Ice Age, ice sheets covered all over Antarctica, large parts of Europe, North America, South America, and small areas of Asia, in North America stretching over Greenland and Canada And parts of the northern United States glacial river glacial remains can still be seen in parts of the world map, including Greenland and Antarctica.
But the glaciers did not just sit there, there was a lot of movement over time, and there were about 20 turns when the glaciers progressed and retreated as they were thawed and frozen. Scientists have identified the four major phases, or ages of the fourth ice age, Gelasan, Calabria, Ionian, and Tarantan.
The climate in the earliest modern era
In general the climate was cooler and drier than it is today, since most of the water on the surface of the earth was icy, there was little rainfall and the precipitation was about half of what it is today, during peak periods with most of the freezing water, it was average Global temperatures from 5 to 10 ° C (9 to 18 ° F) are below current temperature standards.
There was winter and summer during that period; The difference in temperature produced an ice advance, because the cool summer did not completely melt the snow.
Life during the earliest modern era
As Homo sapiens evolved, many vertebrates, especially large mammals, succumbed to the harsh climatic conditions of this period.
One of the richest sources of information about life in this era can be found at La Brea Tar Pits in Los Angeles, where the remains of everything from insects to plant life to animals have been preserved, including the partial skeleton of humans and females and almost complete mystical mammoths.
In addition to the mystical mammoths, mammals such as Sword-toothed cats (Smilodon), terrestrial sloths (Megatherium) and mastodons wandered to Earth during this period, other mammals that thrived during this period include moon moon, tenrecs hedgehog-like creatures and macrocenia-style llamas and camels .
Although many vertebrates became extinct during this period, mammals familiar to us today can be found including monkeys, cows, deer, rabbits, kangaroos, kittens, bears, family members of dogs and cats.
Unlike a few birds that were classified as dinosaurs, most notably the Titanis, there were no dinosaurs during the Pleistocene era, they became extinct at the end of the Cretaceous, more than 60 million years before the Pleistocene era began.
The species of birds flourished during this period, including members of the families of ducks, geese, falcon and eagle, there were also some birds that did not fly like ostriches, wild trips and cattle, birds that did not fly also did not succeed, as they had to compete with mammals and other creatures to obtain supplies Limited food and water, as much of the water is frozen.
Alligators, lizards, turtles, snakes and other reptiles flourished during this period.
As for plants, they were somewhat limited in many areas, there were some scattered conifers, including pine, cypress, and greek trees, along with some broad-leaved trees such as beech and oak, on the ground, there were prairie grasses as well as family members Tulips, orchids and roses.
Mass extinction in the earliest modern era
About 13,000 years ago, more than three quarters of the large animals died in the Ice Age, including mystical mammoths, mastodons, toothed tigers and giant bears,; Scientists have argued for years about the cause of extinction, with both major hypotheses overfishing and climate change insufficient to explain massive death.
Recent research indicates that an extraterrestrial body, perhaps a comet, about 3 miles wide, may have exploded over southern Canada, nearly eliminating ancient Paleolithic culture as well as large animals such as mastodons and mammoths.
Surrounding environments in the earliest modern era
The environment around the ice sheets was noticeably different from those of today in these former glaciers, temperatures were much lower, and the constantly frozen soil area evolved around the southern margin of ice sheets in both North America and Eurasia, this region was relatively narrow in central North America , At a distance of 200 kilometers, but in Europe and Russia extended hundreds of kilometers to the south of the ice margin, the average annual temperature near the ice margin was about -6 ° C or cooler and increased away from the ice margin to about 0 ° C near The southern range of permafrost. Compared to current conditions, the average air temperature was around 12 degrees to 20 degrees Celsius cooler near the ice margin, these conditions are indicated by the extensive wedge ice and ground wedge molds, which are forms of ice wedges and tundra polygons Formed only today in areas with constant permanent ice, frost activity was intensified by freezing and thawing, and in areas where more ankle accumulation and large mass fields formed along the slopes and sides of the valley, mass waste and corrosion of many materials were also intensified From the slopes in the areas surrounding the mountain, deposits and terrain from this activity are known from the British Isles, Northern Europe, and what was formerly known as the Soviet Union.