timelineofearth

Earth creation

45,000 BCE

-4.5 billion years ago
Earth was created by the gathering of space dust and fragments. As this gathering occurred, the increasing mass, known as proto-Earth, was squeezed by gravity, resulting in a rise in temperature. This temperature increase, combined with extra heat from radioactive decay, made proto-Earth a hot liquid mass. As proto-Earth cooled down, it "organized" itself based on density, resulting in a layered structure.

Emergence of life

35,000 BCE

-3.5 billion years ago
This information comes from rock samples discovered in Western Australia and South Africa. These rocks have organic materials, like carbon and hydrogen, which are essential for life.An important aspect of these organic materials is their isotopic signature, which shows low levels of carbon-13. This indicates that the carbon in these materials was altered by living organisms, as natural processes usually prefer the lighter carbon-12 isotope.

Oxygenation of the Atmosphere

2700 BCE

-2.7 billion years ago
Cyanobacteria, a kind of bacteria, started producing oxygen (O2) via photosynthesis. This action, known as oxygenation, discharged oxygen into the air. As cyanobacteria kept producing oxygen, it started to build up in the atmosphere.This signified an important change in Earth's history, as oxygen opened the door for the development of more intricate life forms, such as animals and plants..

Multicellular Organisms appeared

1800 BCE

-1800 million years ago
Grypania spiralis is important because it is thought to be one of the earliest known multicellular living beings on Earth.As a multicellular being, Grypania spiralis consisted of numerous cells that collaborated.This marked a major advancement from single-celled organisms, which were common until that time. Being multicellular enabled more complexity, variety, and adaptability, opening the door for the many types of life forms we observe today..

First chloroplasts

1600 BCE

-1600 million years ago
Origin of chloroplasts similar to mitochondria, chloroplasts came from a symbiotic event where a photosynthetic bacterium (probably a cyanobacterium) was absorbed by a host eukaryote. Eventually, the absorbed organism developed into a specialized photosynthetic organelle..

Cambrian Explosion

540 BCE

-520 Million years ago
During this time, life changed quickly. Many new animal types emerged, including the forebears of today’s animals like arthropods, mollusks, and vertebrates

First vertebrates

521 BCE

-525 million years ago
In the Cambrian period, a new type of animal appeared: small jawless fish, 2 to 3 cm long, with basic vertebrae and a brain protected by a skull. These were the first vertebrates, marking a major evolutionary step. Their simple structure laid the foundation for the evolution of fish, amphibians, reptiles, birds, and mammals.

First Land Plants

470 BCE

-470 million years ago
Plants such as mosses started to develop on land, changing the surroundings. They generated oxygen and formed new habitats, making it possible for land animals to exist..

Dinosaurs and Mammals Appear

230 BCE

-230 million years ago
Dinosaurs first appeared in the Triassic Period and ruled the Mesozoic Era. They varied from small species less than half a meter to huge ones more than 23 meters long. Some changed into flying dinosaurs, which turned into today's birds. Although commonly mistaken for dinosaurs, Dimetrodons were actually early reptiles from the Permian Period, existing about 40 million years before dinosaurs..

extinction

66 BCE

-66 million years ago
The Cretaceous-Paleogene extinction, a well-known mass extinction, signified the conclusion of the dinosaurs. Approximately 76% of species and 40% of genera were eliminated. Researchers think a 10-km asteroid hit Earth, leading to significant climate changes and environmental breakdown. This extinction allowed mammals to prosper and diversify without dinosaurs..

Modern Humans appearence

2 BCE

-0,2 MYA
Modern humans have significantly influenced Earth’s ecosystems, but we have only existed for a brief period in its history. We emerged in Africa around 300,000 years ago from previous human species who belonged to a category of primates known as hominids.Humans dispersed worldwide and created cultures, societies.The world we inhabit was formed by key components like carbon, oxygen, nitrogen, and sulfur, vital for all life, are cycled through processes mainly controlled by microbes.