A History of Bodies, Brains, and Minds

Francisco Aboitiz is a professor at the Medical School and the director of the Interdisciplinary Center for Neuroscience at Pontificia Universidad Católica de Chile. A History of Bodies, Brains, and Minds: The Evolution of Life and Consciousness (MIT Press, 2024) tells the story of life and nervous systems. It introduces the conceptual framework and terminology of evolution, gives a great overview of our current knowledge and a thorough discussion of open questions.

The first part defines two basic concepts: evolution and life. Surprisingly, we learn that the first definition is more straightforward. If you are challenged by some terminology in the later chapters - like phylogeny, ontogeny, or the different types of homology - it is highly recommended to revisit the definitions in the first chapter.

The story begins in the second part. Chapter 3 introduces multiple theories on how the first cells might have appeared. In the next chapter, these cells start to form more complex, multicellular organisms. Chapter 5 is dedicated to the main characteristics and early history of neurons.

In the third part, we get acquinted with more complex animals. In chapter 6 with the bilaterians, in chapter 7 and 8 with the vertebrates and their nervous system, in chapter 9 with mammals. Chapter 10 provides a deep dive into the neocortex and its role in cognition.

The fourth part of the book is about "a singular ape". Chapter 11 describes the history of primates, focusing on Hominins. It goes into details on various aspects like walking, the growth of brains, toolmaking, and social life. Chapter 12 describes the evolution of vocal communication. Chapter 13 discusses how speech has influenced communication and social life. Chapter 14 explores numerous open questions around consciousness. How to define it? When and how did it emerge in evolution? Which animals are conscious and in which ways? After this long history, chapter 15 arrives in the present and the future. What are some current evolutionary trends? How do cultural and technological changes influence our nervous systems?

In our conversation with Professor Aboitiz, we focused on a few remarkable milestones in this story. For start, he outlined some theories how life might have begun.

Then a huge jump in time followed: How the first mammals appeared and survived in a world dominated by dinosaurs. Professor Aboitiz elaborated on how the brains of mammals differ from the brains of other vertebrates. He described the cerebral cortex, a new part in the mammalian brain. The role of senses changed significantly: The early mammals had worse vision, but better smell, touch, and audition compared to other vertebrates. Changes in the anatomy of the head and neck supported these more developed senses. The enhanced olfactory system is also related to the hippocampus, where some new skills appeared: advanced spatial orientation and short-term memory.

The next milestone we discussed in detail is the appearance of language. Professor Aboitiz shared some fascinating facts about the vocal communication of birds and primates. He explained the connection between toolmaking and language. He described the speech loop and the connection between working memory and talking. He proposes that manual gestures and vocal communication have evolved together, and communication has always been multi-modal.

The last part of our conversation focused on the current and future situation. How culture and technology has changed our nervous system, e.g. how a brain area is particularly involved in reading. Professor Aboitiz also discussed the more recent technological innovations and their effects on society and the environment. He introduced the social projects conducted by the Interdisciplinary Center for Neuroscience. The project RIEN (Robótica Integral Educativa & Neurociencia) facilitates workshops where kids work in teams with rotating roles to build and program robots.