A fractal is any geometric pattern that occurs again and again, at different sizes and scales, within the same object. This "self-similarity" can be seen throughout nature, for example in a ...

In most vertebrates, skin appendages such as hair, feathers, or scales originate from placodes—small, specialized skin regions whose spatial organization is controlled by well-conserved genetic ...

An optical illusion is a visual phenomenon where the brain misinterprets what the eyes perceive, creating a false or misleading impression of reality. This occurs because the brain processes visual ...