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If the deep marine hydrothermal setting was the site for the origin of life, then abiogenesis could have happened as early as 4.0-4.2 Gya. If life evolved in the ocean at depths of more than ten meters, it would have been shielded both from impacts and the then high levels of ultraviolet radiation from the sun.
Ichthys was adopted as a Christian symbol.. The ichthys or ichthus (/ ˈ ɪ k θ ə s / [1]), from the Greek ikhthū́s (ἰχθύς, 1st cent.AD Koine Greek pronunciation: [ikʰˈtʰys], "fish") is (in its modern rendition) a symbol consisting of two intersecting arcs, the ends of the right side extending beyond the meeting point so as to resemble the profile of a fish.
Origin: Ancient Greek: ἀ-, ἀν-(a, an-). Meaning: a prefix used to make words with a sense opposite to that of the root word; in this case, meaning "without" or "-less". This is usually used to describe organisms without a certain characteristic, as well as organisms in which that characteristic may not be immediately obvious.
A similar developmental origin suggests they are the same structure, and thus likely derived from a common ancestor. When a group of organisms share a homologous structure that is specialized to perform a variety of functions to adapt different environmental conditions and modes of life, it is called adaptive radiation.
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 ...
A fish (pl.: fish or fishes) is an aquatic, anamniotic, gill-bearing vertebrate animal with swimming fins and a hard skull, but lacking limbs with digits.Fish can be grouped into the more basal jawless fish and the more common jawed fish, the latter including all living cartilaginous and bony fish, as well as the extinct placoderms and acanthodians.
The biosphere is postulated to have developed, from the origin of life onwards, at least some 3.5 billion years ago. [79] The earliest evidence for life on Earth includes biogenic graphite found in 3.7 billion-year-old metasedimentary rocks from Western Greenland [ 74 ] and microbial mat fossils found in 3.48 billion-year-old sandstone from ...
Experimentalists used a variety of terms for the study of the origin of life from nonliving materials. Heterogenesis was applied to the generation of living things from once-living organic matter (such as boiled broths), and the English physiologist Henry Charlton Bastian proposed the term archebiosis for life originating from non-living materials.