Building a visual system from scratch: The evolution and functional development of fan worm radiolar eyes.

How does an eye evolve?

Advanced eyes such as those in vertebrates, arthropods and cephalopods are the results of a multitude of incremental advancements in complexity and optical sophistication over enormous timescales. To truly understand how eyes evolved, I look to simpler visual systems.

I have personally developed sabellid fan worms as an exciting opportunity for exploring the fundamental questions of eye evolution.

These tube-dwelling marine polychaetes project a feathery crown of specialised tentacles out of their tubes to filter-feed.

Since this is the only part of the animal exposed to the world, they have evolved a variety of unique eyes on these tentacles. These eyes respond to looming threats and trigger a rapid retraction of the worm down into its tube.

Fan worm eyes are notable because extant species display all the incremental steps from eye-lessness to simple scattered photoreceptors, and on to sophisticated compound eyes.

My project will use cutting-edge molecular and neurological techniques to identify the developmental factors that control eye evolution and elaboration in these worms. I will use advanced 3D imaging techniques to map the visual circuits during larval development.

Furthermore, I will harness the remarkable regenerative properties of these worms in order to probe how new eyes are formed and integrated into the nervous system in order to affect behaviour.