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  2. Phylogenetic inertia - Wikipedia

    en.wikipedia.org/wiki/Phylogenetic_inertia

    Evolution of fish to tetrapods. The basic body plan has been phylogenetically constrained. Most terrestrial vertebrates have a body plan that consist of four limbs. The phylogenetic inertia hypothesis suggests that this body plan is observed, not because it happens to be optimal, but because tetrapods are derived from a clade of fishes (Sarcopterygii) which also have four limbs.

  3. Evolution of cells - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_cells

    As duplex DNA became the predominant form of the genetic material, the mechanism of genetic recovery evolved into the more complex process of meiotic recombination, found today in most species. It thus appears likely that sexual reproduction arose early in the evolution of cells and has had a continuous evolutionary history.

  4. Timeline of the evolutionary history of life - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_the...

    In biology, evolution is any change across successive generations in the heritable characteristics of biological populations. Evolutionary processes give rise to diversity at every level of biological organization , from kingdoms to species , and individual organisms and molecules , such as DNA and proteins .

  5. Timeline of human evolution - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_human_evolution

    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.

  6. Evolution - Wikipedia

    en.wikipedia.org/wiki/Evolution

    Evolution is the change in the heritable characteristics of biological populations over successive generations. [1] [2] It occurs when evolutionary processes such as natural selection and genetic drift act on genetic variation, resulting in certain characteristics becoming more or less common within a population over successive generations. [3]

  7. History of life - Wikipedia

    en.wikipedia.org/wiki/History_of_life

    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 ...

  8. Introduction to evolution - Wikipedia

    en.wikipedia.org/wiki/Introduction_to_evolution

    However speciation has been observed in present-day organisms, and past speciation events are recorded in fossils. [ 73 ] [ 74 ] [ 75 ] Scientists have documented the formation of five new species of cichlid fishes from a single common ancestor that was isolated fewer than 5,000 years ago from the parent stock in Lake Nagubago. [ 76 ]

  9. Macroevolution - Wikipedia

    en.wikipedia.org/wiki/Macroevolution

    Macroevolution addresses the evolution of species and higher taxonomic groups (genera, families, orders, etc) and uses evidence from phylogenetics, [5] the fossil record, [9] and molecular biology to answer how different taxonomic groups exhibit different species diversity and/or morphological disparity.