How Can Development And Plasticity Contribute To Understanding Evolution Of The Human Brain

Humans usually attribute themselves the prerogative of being the pinnacle of evolution. They have large brains with many billion neurons and glial cells, trillions of synapses and besides all, a plastic hardware that may change either subtly or strongly in response to the external environment and internal, mental commands. With this hypercomplex apparatus, they are capable of very sophisticated inward computations and outward behaviors that include self-recognition, metacognition, different forms of language expression and reception, prediction of future events, planning and performing long streams of motor acts, subtle emotional feelings, and many other surprising, almost unbelievable properties. The main challenge for research is: how do we explain this gigantic achievement of evolution? Is it a direct consequence of having acquired a brain larger than our primate ancestors, with huge numbers of computational units? Would it be determined by a particular way these units came to relate to each other, building up logic circuits of powerful capacities? What along development has “made the difference” for the construction of such a complex brain machine? How much of this complexity is innate, how much is sculpted by influence of the external world, by social interaction with our human fellows, and by the history of our own mental trajectory along life? Many specific questions can be asked (albeit not necessarily answered so far) to this purpose: (1) which genomic characteristics make us unique among primates? (2) which of developmental events during and beyond embryogenesis define our brain – prolonged neurogenesis? permanent circuit (re)formation? dynamic synaptogenesis? regressive sculpting of the hardware? all of them? (3) is there anything special about plasticity of the human brain that allows us to build the exquisite individual variability characteristic of our brains? Neuroscience is in need of a synthesis. Perhaps associating concepts derived from developmental neurobiology with evolutionary morphology and physiology, together with those that photograph the human brain in action under influence of the external world, would turn on a light at the end of the tunnel, and we would be able to understand what humans do have that is special – if anything – to explain our success in the Earth.

Humans usually attribute themselves the prerogative of being the pinnacle of evolution. They have large brains with many billion neurons and glial cells, trillions of synapses and besides all, a plastic hardware that may change either subtly or strongly in response to the external environment and internal, mental commands. With this hypercomplex apparatus, they are capable of very sophisticated inward computations and outward behaviors that include self-recognition, metacognition, different forms of language expression and reception, prediction of future events, planning and performing long streams of motor acts, subtle emotional feelings, and many other surprising, almost unbelievable properties. The main challenge for research is: how do we explain this gigantic achievement of evolution? Is it a direct consequence of having acquired a brain larger than our primate ancestors, with huge numbers of computational units? Would it be determined by a particular way these units came to relate to each other, building up logic circuits of powerful capacities? What along development has "made the difference" for the construction of such a complex brain machine? How much of this complexity is innate, how much is sculpted by influence of the external world, by social interaction with our human fellows, and by the history of our own mental trajectory along life? Many specific questions can be asked (albeit not necessarily answered so far) to this purpose: (1) which genomic characteristics make us unique among primates? (2) which of developmental events during and beyond embryogenesis define our brain - prolonged neurogenesis? permanent circuit (re)formation? dynamic synaptogenesis? regressive sculpting of the hardware? all of them? (3) is there anything special about plasticity of the human brain that allows us to build the exquisite individual variability characteristic of our brains? Neuroscience is in need of a synthesis. Perhaps associating concepts derived from developmental neurobiology with evolutionary morphology and physiology, together with those that photograph the human brain in action under influence of the external world, would turn on a light at the end of the tunnel, and we would be able to understand what humans do have that is special - if anything - to explain our success in the Earth.

How we raise young children is one of today's most highly personalized and sharply politicized issues, in part because each of us can claim some level of "expertise." The debate has intensified as discoveries about our development-in the womb and in the first months and years-have reached the popular media. How can we use our burgeoning knowledge to assure the well-being of all young children, for their own sake as well as for the sake of our nation? Drawing from new findings, this book presents important conclusions about nature-versus-nurture, the impact of being born into a working family, the effect of politics on programs for children, the costs and benefits of intervention, and other issues. The committee issues a series of challenges to decision makers regarding the quality of child care, issues of racial and ethnic diversity, the integration of children's cognitive and emotional development, and more. Authoritative yet accessible, From Neurons to Neighborhoods presents the evidence about "brain wiring" and how kids learn to speak, think, and regulate their behavior. It examines the effect of the climate-family, child care, community-within which the child grows.

Why our human brains are awesome, and how we left our cousins, the great apes, behind: a tale of neurons and calories, and cooking. Humans are awesome. Our brains are gigantic, seven times larger than they should be for the size of our bodies. The human brain uses 25% of all the energy the body requires each day. And it became enormous in a very short amount of time in evolution, allowing us to leave our cousins, the great apes, behind. So the human brain is special, right? Wrong, according to Suzana Herculano-Houzel. Humans have developed cognitive abilities that outstrip those of all other animals, but not because we are evolutionary outliers. The human brain was not singled out to become amazing in its own exclusive way, and it never stopped being a primate brain. If we are not an exception to the rules of evolution, then what is the source of the human advantage? Herculano-Houzel shows that it is not the size of our brain that matters but the fact that we have more neurons in the cerebral cortex than any other animal, thanks to our ancestors' invention, some 1.5 million years ago, of a more efficient way to obtain calories: cooking. Because we are primates, ingesting more calories in less time made possible the rapid acquisition of a huge number of neurons in the still fairly small cerebral cortex—the part of the brain responsible for finding patterns, reasoning, developing technology, and passing it on through culture. Herculano-Houzel shows us how she came to these conclusions—making “brain soup” to determine the number of neurons in the brain, for example, and bringing animal brains in a suitcase through customs. The Human Advantage is an engaging and original look at how we became remarkable without ever being special.

Infants and children are the often-ignored heroes when it comes to understanding human evolution. Evolutionary pressures acted upon the young of our ancestors more powerfully than on adults, and changes over the course of development in our ancestors were primarily responsible for the species and the people we have become. This book takes an evolutionary developmental perspective, emphasizing that developmental plasticity--the ability to change our physical and psychological selves early in life--is the creative force in evolution, with natural selection serving as a filter, eliminating novel developmental outcomes that did not benefit survival. This book is about becoming--of becoming human and of becoming mature adults. Bjorklund asks, "How can an understanding of human development help us better understand human evolution?" Then, turning the relation between evolution and development on its head, Bjorklund demonstrates how an understanding of our species' evolution can help us better understand current development and how to better rear successful and emotionally healthy children.

First Published in 1995. Routledge is an imprint of Taylor & Francis, an informa company.

This unique volume is one of the first of its kind to examine infancy through an evolutionary lens, identifying infancy as a discrete stage during which particular types of adaptations arose as a consequence of certain environmental pressures. Infancy is a crucial time period in psychological development, and evolutionary psychologists are increasingly recognizing that natural selection has operated on all stages of development, not just adulthood. The volume addresses this crucial change in perspective by highlighting research across diverse disciplines including developmental psychology, evolutionary developmental psychology, anthropology, sociology, nutrition, and primatology. Chapters are grouped into four sections: Theoretical Underpinnings Brain and Cognitive Development Social/Emotional Development Life and Death Evolutionary Perspectives on Infancy sheds new light on our understanding of the human brain and the environments responsible for shaping the brain during early stages of development. This book will be of interest to evolutionary psychologists and developmental psychologists, biologists, and anthropologists, as well as scholars more broadly interested in infancy.

The first comprehensive synthesis on development and evolution: it applies to all aspects of development, at all levels of organization and in all organisms, taking advantage of modern findings on behavior, genetics, endocrinology, molecular biology, evolutionary theory and phylogenetics to show the connections between developmental mechanisms and evolutionary change. This book solves key problems that have impeded a definitive synthesis in the past. It uses new concepts and specific examples to show how to relate environmentally sensitive development to the genetic theory of adaptive evolution and to explain major patterns of change. In this book development includes not only embryology and the ontogeny of morphology, sometimes portrayed inadequately as governed by "regulatory genes," but also behavioral development and physiological adaptation, where plasticity is mediated by genetically complex mechanisms like hormones and learning. The book shows how the universal qualities of phenotypes--modular organization and plasticity--facilitate both integration and change. Here you will learn why it is wrong to describe organisms as genetically programmed; why environmental induction is likely to be more important in evolution than random mutation; and why it is crucial to consider both selection and developmental mechanism in explanations of adaptive evolution. This book satisfies the need for a truly general book on development, plasticity and evolution that applies to living organisms in all of their life stages and environments. Using an immense compendium of examples on many kinds of organisms, from viruses and bacteria to higher plants and animals, it shows how the phenotype is reorganized during evolution to produce novelties, and how alternative phenotypes occupy a pivotal role as a phase of evolution that fosters diversification and speeds change. The arguments of this book call for a new view of the major themes of evolutionary biology, as shown in chapters on gradualism, homology, environmental induction, speciation, radiation, macroevolution, punctuation, and the maintenance of sex. No other treatment of development and evolution since Darwin's offers such a comprehensive and critical discussion of the relevant issues. Developmental Plasticity and Evolution is designed for biologists interested in the development and evolution of behavior, life-history patterns, ecology, physiology, morphology and speciation. It will also appeal to evolutionary paleontologists, anthropologists, psychologists, and teachers of general biology.