© 2017 Journal of the Practice of Cardiovascular Sciences | Published by Wolters Kluwer - Medknow 61 Letter to Editor “100,000 years ago, at least six human species inhabited the earth. Today there is just one US.” This provocative book challenges everything we believed and makes us rethink all that we have ever read. This is a book which is entertaining and yet challenging all our concepts. The Homo sapiens brain is 2% of the body weight but consumes 25% of the body energy. Walking erect paid its price: There was high mortality in childbirth because the large head of the baby lead to death and early birth lead to better survival. Early birth meant that the baby needed to be looked after. Therefore, the mother had to look after the baby, and this could only be possible in a tribal system where the mother could be looked after. Evolution thus favored forming strong ties and large tribes. Yuval Noah Harari is an Israeli Professor of History at the Hebrew University of Jerusalem. He wrote “Sapiens” originally in Hebrew and was later translated to other languages including English. The book is organized into four main parts covering last 70,000 years of human history. In 466 pages, Harari takes us through an exciting journey through human history. This is a summary of the book: • The cognitive revolution – Harari argues that it is our ability to talk and believe in collective myth that led to the unprecedented growth of the human species. He argues that it is this ability that enabled us to be the only dominant human species on the planet. This part also takes a look at the day-to-day lives of early humans and explores the link between human growth and extinction of other animal species • The agricultural revolution ‑ Harari argues that for the farmers, this revolution mainly offered suffering and death. This is an interesting conclusion since we think about agricultural evolution as a major achievement of the human species. In more recent times, we have even started romanticizing farming and agriculture. This part also covers the evolution of language and bureaucracy • The uniication of humanity – Harari argues that even though human culture has been in constant lux through the centuries, there has always been a deinite direction to where we are going. Humans across the planet now form one large family. This part also explores the roles played by money, religion, and imperial vision in the uniication of humanity • The scientiic revolution – This section explores some of the reasons behind rapid industrial and scientiic growth of European nations. Harari argues such a rapid advance is made possible by our acceptance of the fact that we know little about the world around us. It is our acceptance of ignorance that fuelled rapid scientiic innovations Harari writes that 100,000 years ago, H. sapiens was just one of a number of different human species, all competing for supremacy. Just as today, we see different species of bears or pigs, there were different species of humans. While our own ancestors lived mainly in East Africa, our relatives’ homo neanderthalensis, better known as Neanderthals, inhabited Europe. Another species, Homo erectus, populated Asia, and the island of Java was home to homo soloensis. Each species adapted to its own environment. Some were big, fearsome hunters, while others were dwarf-like plant gatherers. Today, of course, there is just one human species alive. How did we H. sapiens become so successful and others did not? About 70,000 years ago, H. sapiens underwent a “cognitive revolution,” Harari writes, which gave them the edge over their rivals to spread from East Africa across the planet. What made H. sapiens so successful is that we are the only animals who are capable of large-scale cooperation. We know how to organize ourselves as nations, companies, and religions, giving us the power to accomplish complex tasks • H. sapiens have the special ability to unite millions of strangers around commons myths. Ideas such as freedom, human rights, gods, laws, and capitalism exist in our imaginations, yet they can bind us together and motivate us to cooperate on complex tasks. In summary, this is a book worth reading, with its thought-provoking stories and sometimes unusual ideas, witty language, and its conclusion. Sapiens: A Brief History of Humankind Author : Yuval Noah Harari Language : English Published by : Harper Price : INR 388 Pages : 464 ISBN : 9780062316097 [Downloaded free from http://www.j-pcs.org on Monday, July 17, 2017, IP: 124.13.103.26]