Innovation is the breaking of an adaptive pattern through the emergence of phenotypic novelty, sometimes corresponding to a new ecological function. Phenotypes in biology include anatomical, physiological and behavioral traits, such as bird wings permitting flight. Innovations are also obviously a part of cultural and technological evolution and include behavioral norms, institutions, and tools. Importantly, there are considerable analogies between innovations in biology, culture, and technology, suggesting that the same driving processes come into play.
I mentioned the example of bird wings permitting flight. Wings are the phenotype – flight is the function. Both emerged as novelties in certain dinosaur lineages, but wings serve many other functions in modern-day bird species such as paddling in water birds, courting displays, and thermoregulation. And of course, the function of flight has been lost or reduced in some bird species. Winged flight has also emerged in other animal lineages, such as the insects, and some of the same generic structures of bird wings are found in gliding mammals and reptiles. Anatomical structures permitting the use of air for displacement has therefore emerged independently many times. So innovation may derive from a single chain of events (such as photosynthesis), or be a more inevitable occurrence arising in multiple independent lineages (gliding and active flight).