The Origins of Consciousness: Thoughts of the Crooked-Headed Fly

This new book, by Giorgio Vallortigara, continues his discussion of apparently complex neurological mechanisms in simple animals. He moves on from his last book, Born Knowing: Imprinting and the Origins of Knowledge, which discusses chick behavior, indicating innate knowledge at birth and the ability to perform some kinds of abstract reasoning without language. This book is comparatively more varied and discusses several different experiments involving much simpler organisms in an attempt to clarify the origin and function of consciousness. Because of the density of the material and the brevity of the book, I found it less compelling than his last one. There are eclectic elements to Vallortigara's writing style, and this book even includes two poems by Emily Dickinson!

One of the most interesting experiments to me was one in which bees were trained to identify paintings by Monet and Picasso. After the initial training, they were generally able to discriminate other paintings by Monet and Picasso. There is also a study of horseshoe crabs, which are actually more closely related to spiders than crabs. They have two primitive eyes which, with their neurological system, allow them to discern visual edges. There is an experiment with cockroaches which indicates that their visual system is similar to that of humans.

The experiment with the crooked-headed fly of the title seems to indicate that this fly possesses a neurological structure that contains a model for the external world around it, and that new external stimuli are compared to the standing model in order to assess their reality. In this instance, the fly's head had been rotated on its body from its normal position. When new experiences don't match the existing model, the fly may freeze. Vallortigara's main thesis is that moving organisms, as opposed to stationary ones, as a matter of survival have evolved the neurological equivalent of a map that shows how their bodies are oriented in relation to objects in the external world. He expands this to say that this is the origin of consciousness, and that consciousness is not an emergent phenomenon that exists only in animals with large brains, such as H. sapiens.

I finally figured out, several years ago, that "consciousness" is actually a buzzword that is often used by people who implicitly believe that ours is the only species to have reached that exalted level. In this respect, I am very much in agreement with Vallortigara's tendency to demythologize our place in the universe. Whether or not this experiment proves his conclusion, I already agreed with Vallortigara that many species share characteristics that have enabled their survival with other species; it makes sense that survival-based characteristics may also work in other species. Not only do we inhabit the same universe, but we inhabit the same planet, where all currently known life has evolved.

There is also some discussion in the book about how animals with very small brains manage to survive, given their limited neurological capacities. Vallortigara thinks that social insects may compensate for this with specialized jobs within the hive: one insect doesn't have to know all of the jobs.

I am generally in agreement with the ideas expressed in this book and think that most people who think like naturalists probably would. I was also reminded of Thinking, Fast and Slow, by Daniel Kahneman, in which humans do most of their thinking fast, like insects, and reserve larger portions of their brains for more complex matters. I am still amazed to see how quickly flies and hummingbirds react to changes in their environments. Larger animals may have the capacity to process more complex information, but they are all descendants of smaller animals that never did slow thinking.