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The earliest evidence for life on Earth includes: 3.8 billion-year-old biogenic hematite in a banded iron formation of the Nuvvuagittuq Greenstone Belt in Canada; [30] graphite in 3.7 billion-year-old metasedimentary rocks in western Greenland; [31] and microbial mat fossils in 3.48 billion-year-old sandstone in Western Australia.
The history of life on Earth traces the processes by which living and extinct organisms evolved, from the earliest emergence of life to the present day. Earth formed about 4.5 billion years ago (abbreviated as Ga, for gigaannum) and evidence suggests that life emerged prior to 3.7 Ga. [1] [2] [3] The similarities among all known present-day species indicate that they have diverged through the ...
These fish evolved in shallow and swampy freshwater habitats, where they evolved large eyes and spiracles. Primitive tetrapods ("fishapods") developed from tetrapodomorphs with a two-lobed brain in a flattened skull, a wide mouth and a medium snout, whose upward-facing eyes show that it was a bottom-dweller, and which had already developed ...
Evolutionary theory predicted that since amphibians evolved from fish, an intermediate form should be found in rock dated between 365 and 385 million years ago. Such an intermediate form should have many fish-like characteristics, conserved from 385 million years ago or more, but also have many amphibian characteristics as well.
The hominoids are descendants of a common ancestor.. Homo sapiens is a distinct species of the hominid family of primates, which also includes all the great apes. [1] Over their evolutionary history, humans gradually developed traits such as bipedalism, dexterity, and complex language, [2] as well as interbreeding with other hominins (a tribe of the African hominid subfamily), [3] indicating ...
The first eon in Earth's history, the Hadean, begins with the Earth's formation and is followed by the Archean eon at 3.8 Ga. [2]: 145 The oldest rocks found on Earth date to about 4.0 Ga, and the oldest detrital zircon crystals in rocks to about 4.4 Ga, [34] [35] [36] soon after the formation of the Earth's crust and the Earth itself.
The time span of the Phanerozoic starts with the sudden appearance of fossilised evidence of a number of animal phyla; the evolution of those phyla into diverse forms; the evolution of plants; the evolution of fish, arthropods and molluscs; the terrestrial colonization and evolution of insects, chelicerates, myriapods and tetrapods; and the ...
[1] [50] [51] [52] It is the first tree founded exclusively on molecular phylogenetics, and which includes the evolution of microorganisms. It has been called a "universal phylogenetic tree in rooted form". [1] This tree and its rooting became the subject of debate. [50] [b]