approximately how long ago did our current era begin
View full size image. The Pleistocene Epoch is typically defined as the time period that began about 1.8 million years ago and lasted until about 11,700 years ago. The most recent Ice Age occurred then, as glaciers covered huge parts of the planet Earth.iew full size image. The Pleistocene Epoch is typically defined as the time period that began about 1.8 million years ago and lasted until about 11,700 years ago. The most recent Ice Age occurred then, as glaciers covered huge parts of the planet Earth. Most animal species flourished and became extinct long before the first monkeys and their prosimian ancestors evolved. While the earth is about 4.54 billion years old and the first life dates to at least 3.5 billion years ago, the first primates did not appear until around 50-55 million years ago.That was10-15 million years after the dinosaurs had become extinct.he beginning of the Eocene Epoch (55.8-33.9 million years ago) coincides with the emergence of early forms of most of the placental mammal orders that are present today. In addition, placental mammals with larger bodies and bigger brains began to appear in the fossil record at this time. Dinosaurs lived throughout the Mesozoic Era, which began 245 million years ago and lasted for 180 million years. It is sometimes called the Age of the Reptiles. The era is divided into three periods.45 to 208 million years ago. 1  During the Triassic period, all land on Earth existed as one enormous mass. 2  It was called Pangaea. 3  The supercontinent slowly began to break up during the Triassic Period. Clouds formed as the Earth began to cool, producing enormous volumes of rainwater that formed the oceans. For the next 1.3 billion years (3.8 to 2.5 billion years ago), the Archean Period, first life began to appear and the world’s landmasses began to form.Earth’s initial life forms were bacteria, which could survive in the highly toxic atmosphere that existed during this time.angea formed some 225 million years ago and would evolve into the seven continents we know today. Free oxygen began to build up around the middle of the Proterozoic Period — around 1.8 billion years ago — and made way for the emergence of life as we know it today. It lasted for about four billion years until about 550 million years ago. About 70 percent of the world’s land masses were created in the Archean Era, between 3.8 and 2.5 million years ago. Rodinia, widely recognized as the first supercontinent, formed during the Proterozoic Era, about 2.5 billion years ago.angea formed some 225 million years ago and would evolve into the seven continents we know today. Free oxygen began to build up around the middle of the Proterozoic Period — around 1.8 billion years ago — and made way for the emergence of life as we know it today. About 3.5 billion years ago is what I heard :) 3.5 billion years ago is the oldest direct evidence for life on Earth.lgae is a photosynthetic organism that used to be considered a plant but has been removed from that category because of its lack of roots, stems, and leaves. The evolution o … f photosynthesis took place approximately 2.5 billion years ago. 3.8 billion years ago is the oldest indirect evidence for life on Earth. Indirect evidence is found in 3.8-billion-year-old banded iron deposits (chert) which contain a Carbon 13 to Carbon 14 ratios similar to ratios found in organisms today. 4 people found this useful.lgae is a photosynthetic organism that used to be considered a plant but has been removed from that category because of its lack of roots, stems, and leaves. The evolution o … f photosynthesis took place approximately 2.5 billion years ago. By the end of the Proterozoic Period, Earth was well along in its evolutionary processes leading to our current period, the Holocene Period, or Anthropocene Period, also known as the Age of Man. Thus, about 525 million years ago, the Cambrian Period began.angea formed some 225 million years ago and would evolve into the seven continents we know today. Free oxygen began to build up around the middle of the Proterozoic Period — around 1.8 billion years ago — and made way for the emergence of life as we know it today. The story of human evolution began in Africa about six million years ago and it describes the very long process that our ancestors went through to ultimately become modern humans.he fossils of these early hominids, which lived 2 to 6 million years ago, all come from that continent. Most scientists believe early humans migrated out of Africa into Asia between 2 million and 1.7 million years ago, entering Europe some time within the past 1 million years. Pangea formed some 225 million years ago and would evolve into the seven continents we know today. Free oxygen began to build up around the middle of the Proterozoic Period — around 1.8 billion years ago — and made way for the emergence of life as we know it today.angea formed some 225 million years ago and would evolve into the seven continents we know today. Free oxygen began to build up around the middle of the Proterozoic Period — around 1.8 billion years ago — and made way for the emergence of life as we know it today.
45 to 208 million years ago.