AdvertisementWhat Rotting Fish Reveal About The Fossil RecordFebruary 07, 2010facebookEmailThis sequence of images shows changes to the bodies of Amphioxus, also known as the lancelet, during decay. It has only a primitive proto-spinal column called a notochord, but it is a close relative of vertebrates. The variation in colors is caused by interference between the equipment and the light illuminating the fish.