Earth formed about 4.54 billion years ago from the accretion of dust and rock within the young Solar System. The surface was initially dominated by intense volcanism, frequent asteroid impacts and a turbulent atmosphere rich in carbon dioxide, nitrogen, water vapour, methane and ammonia. Liquid water condensed as the planet cooled, forming the first oceans while the crust stabilised into early proto-continents - wikipedia 
HTML5 mp4 https://david.hitchhikers.earth/assets/history-of-the-earth/History%20of%20the%20Earth%20%5BQ1OreyX0-fw%5D.mp4#t=16 History of Earth
During this period Earth lacked free oxygen. Radiation from the young Sun, lightning and hydrothermal activity created a chemical environment capable of producing organic molecules such as amino acids, simple sugars and lipid structures. These compounds accumulated in the oceans and around volcanic vents.
# The First Life (c. 4.2–3.5 Billion Years Ago) Life is thought to have emerged around 4.2 billion years ago, soon after liquid water became stable. The most evidence-supported locations for life’s origin are hydrothermal vent systems on the ocean floor. These environments provided steep chemical gradients, natural mineral catalysts and protective conditions shielded from solar radiation.
The first organisms were simple self-replicating molecules enclosed within lipid membranes. Over time they evolved into prokaryotic cells resembling modern bacteria and archaea. These early microbes gained energy through chemical reactions with sulphur, iron and hydrogen compounds. The earliest fossil and isotopic evidence of microbial life dates to around 3.5–3.8 billion years ago - wikipedia
# Photosynthesis and the Rise of Oxygen
3.5–2.4 Billion Years Ago
A major evolutionary breakthrough occurred when some microbes developed the ability to use sunlight to split water and release oxygen. This oxygenic photosynthesis was carried out by cyanobacteria. Over hundreds of millions of years the oxygen released slowly accumulated in the oceans and atmosphere.
A critical tipping point occurred around 2.4 billion years ago during the Great Oxygenation Event. Atmospheric oxygen levels rose sharply, transforming global chemistry. Many anaerobic organisms died out, while others adapted. Oxygen also reacted with methane, causing a cooling period that may have led to widespread glaciation - wikipedia
# Eukaryotes and Complex Cells (2.1–1.2 Billion Years Ago)
The next major transition was the evolution of eukaryotic cells – the complex cell type that all plants, animals and fungi are built from. This likely happened through endosymbiosis, in which one cell engulfed another but instead of digesting it, formed a cooperative relationship. Mitochondria and chloroplasts are the descendants of these ancient symbiotic partners.
Eukaryotic cells allowed for larger size, internal organisation and specialised functions. This paved the way for multicellular life. The first multicellular organisms appeared between 1.2 and 1.0 billion years ago.
- en.wikipedia.org
# The Cambrian Expansion (541 Million Years Ago)
Shortly before the Cambrian period, animals capable of movement and predation began to diversify. The Cambrian explosion saw a dramatic increase in complexity and ecological variety. Most major animal body plans emerged during this time. Hard shells evolved, leaving abundant fossils.
Earth’s continents continued to drift, collide and break apart under plate tectonics. Changing ocean chemistry, sea levels and climates all contributed to bursts of evolutionary innovation and extinction.
- en.wikipedia.org
# Life on Land (c. 470–360 Million Years Ago)
Plants colonised land first, evolving from green algae. They were followed by fungi and arthropods, and later by vertebrates such as early amphibians. The development of seeds, vascular tissues and lungs allowed life to expand into diverse terrestrial environments.
Continents merged into the supercontinent Pangaea by about 335 million years ago, altering global climate and ecosystems. Several mass extinctions punctuated this period, reshaping life and opening evolutionary possibilities.
- en.wikipedia.org
# The Age of Dinosaurs and Mammals (252–66 Million Years Ago)
After the Permian extinction, dinosaurs dominated Earth’s ecosystems for over 180 million years. Mammals remained small and nocturnal but gradually diversified. Continental drift continued as Pangaea broke apart, forming the modern continents and oceans.
The impact event 66 million years ago ended the age of dinosaurs and allowed mammals to radiate into many ecological niches. Primates emerged soon afterward.
- en.wikipedia.org
# Human Origins
(6 Million Years Ago to Present)
Human evolution began with the split between early hominins and other African apes around six million years ago. The genus *Homo* emerged roughly 2.5 million years ago, characterised by increasing brain size and tool use. *Homo sapiens* appeared about 300,000 years ago in Africa.
Humans developed symbolic communication, language, art and complex technologies. Through migration and adaptation, we spread across the planet. Modern societies, agriculture, cities and global civilisation represent the most recent chapter in the four-billion-year story of life’s gradual ascent - wikipedia