Eye - Evolution. 1  Photoreception is phylogenetically very old, with various theories of phylogenesis. [26] 2  Eyes in various animals show adaptation to their requirements. 3  The very earliest eyes, called eyespots, were simple patches of photoreceptor protein in unicellular animals.
Synthetic fibers or fibres are the result of extensive research by scientists to improve on naturally occurring animal and plant fibers. In general, synthetic fibers are created by extruding fiber forming materials through spinnerets into air and water, forming a thread.Before synthetic fibers were developed, artificially manufactured fibers were made from polymers obtained from petro chemicals. These fibers are called synthetic or artificial fibers.oseph Swan invented the first synthetic fiber in the early 1880s. His fiber was drawn from a cellulose liquid, formed by chemically modifying the fiber contained in tree bark.
Rayon is a manufactured regenerated cellulose fiber. It is made from purified cellulose, primarily from wood pulp, which is chemically converted into a soluble compound. It is then dissolved and forced through a spinneret to produce filaments which are chemically solidified, resulting in synthetic fibers of nearly pure cellulose.