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  2. Evolution of fish - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_fish

    The evolution of fish began about 530 million years ago during the Cambrian explosion. It was during this time that the early chordates developed the skull and the vertebral column, leading to the first craniates and vertebrates. The first fish lineages belong to the Agnatha, or jawless fish. Early examples include Haikouichthys.

  3. Timeline of fish evolution - Wikipedia

    en.wikipedia.org/wiki/Timeline_of_fish_evolution

    The evolution of fishes took place over a timeline which spans the Cambrian to the Cenozoic, including during that time in particular the Devonian, which has been dubbed the "age of fishes" for the many changes during that period. The Late Devonian extinctions played a crucial role in shaping the evolution of fish, or vertebrates in general. [1]

  4. Sporophyte - Wikipedia

    en.wikipedia.org/wiki/Sporophyte

    Young sporophytes of the common moss Tortula muralis. In mosses, the gametophyte is the dominant generation, while the sporophytes consist of sporangium-bearing stalks growing from the tips of the gametophytes Sporophytes of moss during spring In flowering plants, the sporophyte comprises the whole multicellular body except the pollen and ...

  5. Evolutionary history of plants - Wikipedia

    en.wikipedia.org/wiki/Evolutionary_history_of_plants

    Land plants evolved from a group of freshwater green algae, perhaps as early as 850 mya, [3] but algae-like plants might have evolved as early as 1 billion years ago. [2] The closest living relatives of land plants are the charophytes, specifically Charales; if modern Charales are similar to the distant ancestors they share with land plants, this means that the land plants evolved from a ...

  6. Fish development - Wikipedia

    en.wikipedia.org/wiki/Fish_development

    Fish embryos go through a process called mid-blastula transition which is observed around the tenth cell division in some fish species. Once zygotic gene transcription starts, slow cell division begins and cell movements are observable. [4] During this time three cell populations become distinguished. The first population is the yolk syncytial ...

  7. Placoderm - Wikipedia

    en.wikipedia.org/wiki/Placoderm

    Rhenanida ("Rhine fish") were flattened, ray-like, bottom-dwelling predators with large, upturned mouths that lived in marine environments. The rhenanids were once presumed to be the most primitive, or at least the closest to the ancestral placoderm, as their armour was made of unfused components—a mosaic of tubercles—as opposed to the ...

  8. Haikouichthys - Wikipedia

    en.wikipedia.org/wiki/Haikouichthys

    3D restoration. Haikouichthys is about 2.5 cm (1 in) long and is narrower than Myllokunmingia, another putative chordate that comes from the same beds. [2] The holotype of Haikouichthys ercaicunensis was found in the Yuanshan member of the Qiongzhusi Formation in the 'Eoredlichia' Zone near Ercai Village in the Haikou Subdistrict (not to be confused with the city of Haikou in Hainan) of Xishan ...

  9. Evolution of tetrapods - Wikipedia

    en.wikipedia.org/wiki/Evolution_of_tetrapods

    The evolution of tetrapods began about 400 million years ago in the Devonian Period with the earliest tetrapods evolved from lobe-finned fishes. [1] Tetrapods (under the apomorphy-based definition used on this page) are categorized as animals in the biological superclass Tetrapoda, which includes all living and extinct amphibians, reptiles, birds, and mammals.