VI. Earth Life Emergence: Development of Body, Brain, Selves and Societies
1. The Evolution of Brain Anatomy and Cognizance
Lotem, Arnon and Joseph Halpern. Coevolution of Learning and Data-Acquisition Mechanisms: A Model for Cognitive Evolution. Philosophical Transactions of the Royal Society. 367/2686, 2012. A Tel-Aviv University zoologist and a Cornell University computer scientist propose an interactive ratchet-like process as creatures find out what is going on around them and their cerebral development for the ability to do so. See also The Evolution of Continuous Learning of the Structure of the Environment by Oren Kolodny, Shimon Edelman, and Arnon Lotem in the Journal of the Royal Society Interface (Online January 2014).
A fundamental and frequently overlooked aspect of animal learning is its reliance on compatibility between the learning rules used and the attentional and motivational mechanisms directing them to process the relevant data (called here data-acquisition mechanisms). We propose that this coordinated action, which may first appear fragile and error prone, is in fact extremely powerful, and critical for understanding cognitive evolution. Using basic examples from imprinting and associative learning, we argue that by coevolving to handle the natural distribution of data in the animal's environment, learning and data-acquisition mechanisms are tuned jointly so as to facilitate effective learning using relatively little memory and computation. We then suggest that this coevolutionary process offers a feasible path for the incremental evolution of complex cognitive systems, because it can greatly simplify learning. This is illustrated by considering how animals and humans can use these simple mechanisms to learn complex patterns and represent them in the brain. We conclude with some predictions and suggested directions for experimental and theoretical work. (Abstract)
Lui, Jan, et al. Development and Evolution of the Human Neocortex. Cell. 146/1, 2011. As many citations here report, novel neuroimaging capabilities, often with 3D streaming video, not possible much earlier, are opening luminous portals on brain anatomy and cognition, not only for humans but across the animal kingdom. With coauthors David Hansen and Arnold Kriegstein, University of California, San Francisco, neuroscientists find our cerebral endowment to be much a “scaled-up primate brain.” Neural growth is then traced and compared via brain cross-sections to elephant, manatee, capybara, ferret, bushbaby, mouse, and brown bat. May we now witness, from our global cognitive vista, life’s long encephalization as if an emergent embryonic maturation of a singular earthly faculty?
Lyon, Pamela. Of What is “Minimal Cognition” the Half-Baked Version? Adaptive Behavior. Online September, 2019. A Flinders University, Adelaide natural philosopher (search) seeks to counter the popular use of this phrase for an early advent of neural faculties. She advises a better appreciation beyond marking any prior time when sensory abilities did not exist or were not present at all. Relative sentience does not and can not spring from insensate nothingness, it must be a natural, incarnate quality. See also Conditions for Minimal Intelligence Across Eukaryota by Paco Calvo and Frantisek Baluska in Frontiers in Psychology and Evolutionary Convergence and Biological Embodied Cognition by Fred Keijzer in Interface Focus (7/20160123, 2017).
“Minimal cognition” is used in certain sectors of the cognitive sciences to make a kind of ontological claim: that a function operating in organisms living today is not a fully fledged version of that function, but, rather, exhibits the minimal requirements for whatever it is, properly conceived. This article argues that “minimal cognition” and “proto-cognitive” were introduced at the turn of this century by researchers seeking to learn directly from evolved behavior, ecology and physiology. An alternative terminology is proposed, based on a phyletically neutral definition of cognition as a biological function; a candidate mechanism is explored; and a bacterial example presented. On this story, cognition is like respiration: ubiquitously present, from unicellular life to blue whales and every form of life in between, and for similar reasons: staying alive requires it. (Abstract excerpt)
Lyon, Pamela. The Cognitive Cell: Bacterial Behavior Reconsidered. Frontiers in Microbiology. Vol.6/Art.264, 2015. The Flinders University, Adelaide cognitive physiologist continues her perceptions of microbial activities as indicative of and distinguished by a deeply abiding intelligence.
Research on how bacteria adapt to changing environments underlies the contemporary biological understanding of signal transduction (ST), and ST provides the foundation of the information-processing approach that is the hallmark of the ‘cognitive revolution,’ which began in the mid-20th century. Yet cognitive scientists largely remain oblivious to research into microbial behavior that might provide insights into problems in their own domains, while microbiologists seem equally unaware of the potential importance of their work to understanding cognitive capacities in multicellular organisms, including vertebrates. Evidence in bacteria for capacities encompassed by the concept of cognition is reviewed. Parallels exist not only at the heuristic level of functional analogue, but also at the level of molecular mechanism, evolution and ecology, which is where fruitful cross-fertilization among disciplines might be found. (Abstract)
Ma, Xiaoya, et al. Complex Brain and Optic Lobes in an Early Cambrian Arthropod. Nature. 490/258, 2012. An international team of Xiaoya Ma and Xianguang Hou, Yunnan University, Gregory Edgecombe, Natural History Museum, London, and Nicholas Strausfeld, University of Arizona, are able for the first time to reconstruct the cerebral anatomy of the invertebrate phylum Arthropoda of insects, arachnids and crustaceans. As a result, rather than finding primitive neural system rudiments, even at this ancient stage an intricate, efficiently developed, neurological apparatus is present.
The nervous system provides a fundamental source of data for understanding the evolutionary relationships between major arthropod groups. Fossil arthropods rarely preserve neural tissue. As a result, inferring sensory and motor attributes of Cambrian taxa has been limited to interpreting external features, such as compound eyes or sensilla decorating appendages, and early-diverging arthropods have scarcely been analysed in the context of nervous system evolution. Here we report exceptional preservation of the brain and optic lobes of a stem-group arthropod from 520 million years ago, Fuxianhuia protensa, exhibiting the most compelling neuroanatomy known from the Cambrian.
MacLean, Paul. The Triune Brain in Evolution. New York: Plenum, 1990. The originator of the famous theory of three subsequent stages of brain development - reptilian, paleomammalian and neomammalian - goes on to propose these are a product of self-organizing, fractal dynamics, which can describe a “fractogenesis.”
Marcus, Gary. The Birth of the Mind. New York: Basic Books, 2004. This work by a New York University neuropsychologist considers how genes influence thought and observes a linear continuity across the entire evolution of brain development as it maintains a basic architecture that expands in size and modular complexity.
Although the nervous system of a flatworm is vastly less complex than ours, the resemblance in overall organization is striking, a consequence of the fact that many of the genes guiding the pattern of the brain of a human relate closely to genes involved in the patterning of the nervous system of the worm. (117)
Marcus, Gary and Jeremy Freeman, eds. The Future of the Brain. Princeton: Princeton University Press, 2014. Into the 2010s, a number of well-financed, high-profile scientific ventures, akin to the human genome project, are underway to achieve a full, three-dimensional atlas of our human cerebral architecture. A prime instance is the Allen Institute for Brain Science, aka Project MindScope, in Seattle funded by Paul Allen and led by Christof Koch. This volume collects a series of contributions to consider how best to proceed and what to avoid. Main sections are Mapping the Brain, Computation, Simulating the Brain, Language, Skeptics, and Implications by leading neuroscientists such as Koch, Marcus, Anthony Zador, George Church (search), Olaf Sporns, David Poeppel, and Leah Krubitzer, which well cover the territory.
As I look to the future, it seems inevitable that neuroscience will continue to move from focusing on components to mapping and modeling their interactions, building on a reconceptualization of the brain as a complex networked system. I expect that this shift towards network neuroscience will lead to fundamentally new insights. As many studies have shown, the organization and architercture of networks from a surprising range of real-world systems (cells to society) express a set of shared and common themes and motifs. While the brain is certainly unique in that it mediates all personal experience, w e may find it does so by following a set of general and universal laws that govern the function of complex networks. (Olaf Sporns, 99)
Marino, Lori. Big Brains do Matter in New Environments. Proceedings of the National Academy of Sciences. 102/5306, 2005. An overview of an article in the same issue (Sol, Daniel, et al. 102/5460, 2005). By a synthesis of this present work on avian brains with other studies, it is possible to perceive a consistent evolutionary pattern of animal encephalization, which seems to be driven by encounters with novel experiences. Feeding innovation, tool use, behavioral repertoire, weather, etc. are factors which impel an enhanced neural architecture and cognitive capacity. Another journal that often reports such research is Brain, Behavior and Evolution.
Marino, Lori. Fraction of Life-Bearing Planets on Which Intelligent Life Emerges, fi, 1961 to the Present. Douglas Vakoch and Matthew Dowd, eds. The Drake Equation: Estimating the Prevalence of Extraterrestrial Life through the Ages. Cambridge: Cambridge University Press, 2015. After two decades as an Emory University neuroscientist and psychologist, Dr. Marino founded and now directs the Kimmela Center for Animal Advocacy. She is noted for studies of and concerns for dolphins and whales (search) and also leads the Nonhuman Rights Project. Her unique theme is that all creatures ought to be viewed as true persons just the same as people. In this chapter an emergent evolutionary continuum of sentient behavior is traced across vertebrate and even invertebrate phyla, which thus bodes well for extraterrestrials. Three main stages are brainlike functions in unicellular organisms, multicellurarity and neurons, and bilateralization and cephalization. But, maybe because of her years in academia, while human sapience brings a self-aware linguistic culture, a teleological, anthropocentric place atop a “scala naturae” is rejected, which seems to me to undercut and contradict.
In this chapter, I trace the history of our conceptions of intelligence through changes and growth in our understanding of brain evolution, genetics, and animal behavior, and present a modern view of intelligence that places human intelligence in an evolutionary context and linked to the multiple intelligences inhabiting this planet. In this chapter, I will discuss these issues in detail and replace these outmoded notions with new information and insights about how and why intelligence evolves and the levels and distribution of intelligence across species on this planet. Modern understanding of intelligence shows that it is continuous across all animal life on Earth and that the human brain is embedded in the evolutionary web of primate brain evolution and contains the hallmarks of nervous-system evolution traced back to the first life forms on this planet. (Abstract excerpts)
Mashour, George and Michael Alkire. Evolution of Consciousness: Phylogeny, Ontogeny, and Emergence from General Anesthesia. Proceedings of the National Academy of Sciences. 110/Supple. 2, 2013. In this “In the Light of Evolution VII: The Human Mental Machinery” edition, University of Michigan Medical School, and University of California, Irvine, neurophysicians draw upon clinical experience to advance an innovative appreciation of realms of knowing awareness. In regard, a recurrence or recapitulation becomes evident from such reawakenings unto both one’s own sentience, and life’s evolutionary stirrings unto a human acumen to similarly witness and remember. As a result, and as other papers here and across the site (Animal Intelligence), a singular animal encephalization is seen to form and arise by degrees from the earliest proto-cellular origins. With reference to “Evolution of the Avian Brain and Intelligence” by Nathan Emery and Nicola Clayton (Current Biology 15/23, 2005), it is said that the old Scala Naturae from simple rudiments to complex cerebra is to be set aside for a modular, concerted and mosaic increase of cognitive anatomy and function from an original archetype, as if a brain Bauplan, from the outset. As many research fields attest, by an integral vista not possible before, life’s evolution does indeed appear as an embryonic developmental gestation of communal bodies, bilateral brains, and proactive cognizance via creatures in communities.
Are animals conscious? If so, when did consciousness evolve? We address these long-standing and essential questions using a modern neuroscientific approach that draws on diverse fields such as consciousness studies, evolutionary neurobiology, animal psychology, and anesthesiology. We propose that the stepwise emergence from general anesthesia can serve as a reproducible model to study the evolution of consciousness across various species and use current data from anesthesiology to shed light on the phylogeny of consciousness. Ultimately, we conclude that the neurobiological structure of the vertebrate central nervous system is evolutionarily ancient and highly conserved across species and that the basic neurophysiologic mechanisms supporting consciousness in humans are found at the earliest points of vertebrate brain evolution. Thus, in agreement with Darwin’s insight and the recent “Cambridge Declaration on Consciousness in Non-Human Animals,” a review of modern scientific data suggests that the differences between species in terms of the ability to experience the world is one of degree and not kind. (Abstract)
Montgomery, John and David Bodznick. Evolution of the Cerebellar Sense. Oxford: Oxford University Press, 2016. University of Auckland, New Zealand, and Wesleyan University, USA neuroscientists provide a dedicated introduction to the advent and advance of a cerebellar sense of self and sense of agency. They go on to say how better understandings of our deep neural heritage can aid human rehabilitations, sports, and technology.
The cerebellum is an intriguing component of the brain. In humans it occupies only 10% of the brain volume, yet has approximately 69 billion neurons; that is 80% of the nerve cells in the brain. The cerebellum first arose in jawed vertebrates such as sharks, and early vertebrates also have an additional cerebellum-like structure in the hindbrain. Shark cerebellum-like structures function as adaptive filters to discriminate 'self' from 'other' in sensory. It is likely that the true cerebellum evolved from these cerebellum-like precursors, and that their adaptive filter functionality was adopted for motor control; paving the way for the athleticism and movement finesse that we see in swimming, running, climbing and flying vertebrates.