Bolder and Better, But Not Simpler: Protein interaction hypotheses for evolution of consciousness James Beran (Montara, CA ) C16
Tubulin, ion channels, proteins that regulate post-translational modifications (PTM Reg proteins), ankyrin--What do these (and other) diverse types of proteins have in common? Evolution of consciousness! More precisely, researchers have proposed that each of these protein types played a role in evolution of consciousness. (Hameroff, 2017; McFadden, 2000; Beran, 2013; Beran, 2018) And each researcher might be correct to an extent--multiple proteins (and their genes) could all have roles in this dramatic feat of nature. (See, e.g., Feinberg et al., 2013, Table 2) But evolution is not like making ratatouille--nature does not simply toss genes and proteins into a pot and stir. Therefore, this work develops a new approach to evolution of consciousness, an approach recognizing that a hypothesis can include more than one type of proteins. Our new approach offers multi-scale hypotheses (Beran, 2019) in which proteins of different types interact. For example, some types of proteins ("evolving proteins") might change significantly (e.g. in amino acid sequence, in expression, etc.) in concert with evolution of consciousness, while other types of proteins ("conserved proteins") might themselves change little but might interact with evolving proteins. We start with a four-scale general summary of evolution of consciousness that includes both interaction between types of proteins and also operations of groups of neurons: Changes occur in a set of evolving proteins due to germ-line changes affecting corresponding genes (genome variation scales), so that proteins of different types interact with each other in a new way (sub-neuron scales); this new way of interacting changes operation of a group of neurons (super-neuron scales), and the changed operation in turn changes a consciousness-related feature of an animal's brain (brain scales). Using this summary, we generate a number of new hypotheses by specifying several possible combinations of interacting proteins, their interactions, and related neuron group operations. Because of its centrality in neuron structure and operation, tubulin plays a role in several of our new hypotheses, ranging from less to more detailed: One hypothesis includes only three types of proteins--tubulin, ankyrin, and ion channels; another adds a fourth--PTM Reg proteins; and a more detailed hypothesis adds several more--microtubule-associated proteins (MAPs), TRIM46, and adhesion proteins such as neurofascin, We also generate other new hypotheses that do not include tubulin. Our comparisons indicate that adding detail to a hypothesis can provide more ways to falsify it but also makes it more complex; therefore, while more detailed hypotheses can be "bolder" in the sense advocated by Popper, they do not follow the scientific preference for simplicity. (Maxwell, 2016) Nevertheless, we propose that more detailed hypotheses about evolution of consciousness can be better: Because they might more closely follow the actual path evolution followed, they offer greater explanatory power than similar hypotheses with fewer scales, fewer protein interactions, and fewer neuron group operations. If well-formulated, detailed protein interaction hypotheses will help us better understand evolution of consciousness.