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Evolution of cells refers to the evolutionary origin and subsequent evolutionary development of cells. Cells first emerged at least 3.8 billion years ago [1][2][3] approximately 750 million years after Earth was formed. [4]
The timeline of human evolution outlines the major events in the evolutionary lineage of the modern human species, Homo sapiens, throughout the history of life, beginning some 4 billion years ago down to recent evolution within H. sapiens during and since the Last Glacial Period. It includes brief explanations of the various taxonomic ranks in ...
The first known mass extinction was the Great Oxidation Event 2.4 billion years ago, which killed most of the planet's obligate anaerobes. Researchers have identified five other major extinction events in Earth's history, with estimated losses below: [11] End Ordovician: 440 million years ago, 86% of all species lost, including graptolites
None. In human genetics, the Mitochondrial Eve (more technically known as the Mitochondrial-Most Recent Common Ancestor, shortened to mt-Eve or mt-MRCA) is the matrilineal most recent common ancestor (MRCA) of all living humans. In other words, she is defined as the most recent woman from whom all living humans descend in an unbroken line ...
After the LECA, some 2 billion years ago, the eukaryotes diversified into a crown group, which gave rise to animals, plants, fungi, and protists. Eukaryogenesis, the process which created the eukaryotic cell and lineage, is a milestone in the evolution of life, since eukaryotes include all complex cells and almost all multicellular organisms.
The age of Earth is about 4.54 billion years; [7] [33] [34] the earliest undisputed evidence of life on Earth dates from at least 3.5 billion years ago according to the stromatolite record. [35] Some computer models suggest life began as early as 4.5 billion years ago. [36] [37] The oldest evidence of life is indirect in the form of isotopic ...
The cell had a lipid bilayer; it possessed the genetic code and ribosomes which translated from DNA or RNA to proteins. The LUCA probably existed at latest 3.6 billion years ago, and possibly as early as 4.3 billion years ago [2] or earlier. The nature of this point or stage of divergence remains a topic of research.
A second merger, 1.6 billion years ago, added chloroplasts, creating the green plants. [31] Eukaryotic cells were created some 2.2 billion years ago in a process called eukaryogenesis. This is widely agreed to have involved symbiogenesis, in which archaea and bacteria came together to create the first eukaryotic common ancestor. This cell had a ...