Iris folding is a paper craft technique that involves folding strips of colored paper in such a way to form a design.The center of the design forms an iris â a shape reminiscent of the iris diaphragm of a camera lens.istory [edit]. Iris folding originated in Holland, where early craft people made their designs using patterned paper cut from the inside of envelopes. Today, crafters use any light weight paper, such as scrapbook paper, origami paper, wrapping paper, the inside of envelopes or pages of magazines. Ribbon is also used.
Extinction is the disappearance of a previously learned behavior when the behavior is not reinforced. In this lesson, learn more about extinction in operant conditioning and test your knowledge with a quiz.
Local extinction or extirpation is the condition of a species that ceases to exist in the chosen geographic area of study, though it still exists elsewhere. Local extinctions are contrasted with global extinctions. Local extinctions may be followed by a replacement of the species taken from other locations; wolf reintroduction is an example of this.