Coacervates are colloidal aggregations of hydrophobic proteins and lipids (lipoid bubbles). They appear as droplets composed of liquid condensates, proteins, lipids, and nucleic acids that are organised in the shape of colloids. Coacervates grew in size by taking up material from surrounding aqueous medium. While growing, the thermodynamic instability split them into smaller units, comparable to daughter cells of budding organisms.

The organic remnants of the past life forms preserved on the sedimentary rocks in the earth is called fossils. They are the best and direct evidences of organic evolution. The age of fossils is calculated by radio-carbon dating and many other methods, which tells us about the era when the life form were alive. Fossils are of many types, like: Actual remains like the cryopreserved Woolly mammoth (of Siberia) or insects preserved in amber. Petrified plants and animals. Skeletal elements like bones, teeth, etc. of an animal. Moulds are the hardened encasements formed in the outer parts of organic remains which later decayed leaving cavities. Casts are hardened pieces of mineral matter deposited in the cavities of moulds.