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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 ...
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.
This phenomenon typically occurs on cool, humid days, but is rare in many climates. Fog and clouds associated with cooling towers can be described as homogenitus, as with other clouds of man-made origin, such as contrails and ship tracks. [46] This phenomenon can be prevented by decreasing the relative humidity of the saturated discharge air.
The earliest known tracks on land named the Zachelmie trackways which are possibly related to icthyostegalians. [80] 375 Ma Tiktaalik, a lobe-finned fish with some anatomical features similar to early tetrapods. It has been suggested to be a transitional species between fish and tetrapods. [81] 365 Ma
Sea cucumbers are typically 10 to 30 cm (4 to 12 in) in length, although the smallest known species are just 3 mm (0.12 in) long, and the largest can reach 3 meters (10 ft). The body ranges from almost spherical to worm-like, and lacks the arms found in many other echinoderms, such as starfish. The anterior end of the animal, containing the ...
t. e. On the Origin of Species (or, more completely, On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life) [ 3] is a work of scientific literature by Charles Darwin that is considered to be the foundation of evolutionary biology. It was published on 24 November 1859. [ 4]
Evolutionary history of plants. A late Silurian sporangium, artificially colored. Green: A spore tetrad. Blue: A spore bearing a trilete mark – the Y -shaped scar. The spores are about 30–35 μm across. The evolution of plants has resulted in a wide range of complexity, from the earliest algal mats of unicellular archaeplastids evolved ...
The history of fluid mechanics is a fundamental strand of the history of physics and engineering. The study of the movement of fluids (liquids and gases) and the forces that act upon them dates back to pre-history. The field has undergone a continuous evolution, driven by human dependence on water, meteorological conditions and internal ...