Looking through a crystal ball: Unravelling the wonders of trilobite eyes

Dr Clare Torney (UK) The weird and wonderful world of trilobite eyes has been subject to study since the late 1800s, but despite being scrutinised intensively over the decades, we are still left questioning how trilobite eyes actually worked due to the loss of their soft parts (that is, photosensitive cells) during the fossilisation process. The numerous strange forms that trilobite eyes come in no doubt plays a role in keeping researchers interested: from the bulging eyes of the Ordovician pelagic trilobite Carolinites to the eyes of Neoasaphus, which stand proud on stalks – trilobite eyes might seem better placed in a sci-fi movie than a palaeontology textbook. However, the study of their eyes can reveal an incredible degree of information, from details of how these extinct marine arthropods lived, to the change in chemistry and temperature of our oceans; and they can even help us understand how animals of today mineralise their (exo)skeletons. Unlike our own eyes, which are made of soft moving parts that allow most of us to focus on whatever we choose whether it be near or far, trilobite eyes in-vivo were actually composed of the hard mineral calcite (crystallised calcium carbonate), which they also used to construct the rest of their exoskeleton (Fig. 1). Fig. 1. An enrolled specimen of Acernaspis orestes from Anticosti Island. The calcitic eyes of trilobites are an extension of their exoskeleton. Although this may come with its advantages (essentially like wearing your safety specs all the time), using calcite to … Read More

To access this post, you must purchase Annual subscription, 12 Month Subscription or Monthly subscription.
%d bloggers like this: