Crested and whiskered auklets nest in hollows on rocky islands in the remote northern Pacific Ocean. To see if their elaborate headdresses helped the birds make their way through the rocks to their nests at night, Jones and Seneviratne went to the Aleutian Islands, captured wild birds and put them in a darkened maze – but first they taped down some birds' decorative feathers.
Infrared camera recordings showed that whiskered auklets (Aethia pygmaea) bumped their heads nearly three times more often if their long head feathers were taped down. Crested auklets (A. cristatella), suffered similarly with their crests taped down, but adding an artificial crest to the naturally unadorned least auklet (A. pusilla) – which also nests on the islands but in more open areas – didn't help these birds avoid bumps. Moreover, Sereviratne says, "birds with longer crests had greater difficulty in navigating inside the maze" when their crests were taped down.
The evolutionary origin of the birds' elaborate head feathers supports the idea that their first job was sensing, says Seneviratne. He adds that the auklets' crests evolved from filoplumes, long hair- or thread-like feathers that lack normal feather structures and are attached to pressure-sensitive cells so they can detect touch. In many birds these feathers are hidden by larger contour or wing feathers, but in the auklets they stick out proudly where they can detect obstacles.
The auklet’s head feathers clearly are not just for looks. But evolutionary theory was not needed to make this discovery, nor does it help in explaining the feathers, or the cellular pressure-sensing mechanisms. In fact, beyond empty speculation evolution has no explanation for how such mechanisms could have arisen on their own. It is a typical example of how evolution is a gratuitous explanation, adding nothing but a “multiplied entity” as Occam put it. We may as well say, with the Aristotelians, that fire is hot because it has the quality of heat. Not only has evolutionary theory badly failed, it is not particularly helpful in doing science. It simply becomes more and more complex as we learn about the world.