Introduction
Carl Sagan's 1977 book The Dragons of Eden: Speculation on Human Evolution is a work of science fiction. A variety of sciences, including anthropology and evolutionary biology, are used to try to explain the evolution of human intellect (Sagan 3). The author addresses the question of quantifying human intelligence capabilities. In our discussion, we would go over the book to see if the author was successful in conveying his major point, as well as some of the flaws that hampered the ideas.
Indicators of Human Intellect
The issue of the brain to body mass ratio is one of the main indications mentioned in the book for determining human intellect (Gibson 10). He relates the brain of other animals to people and provides evidence that the intelligence is as a result of the evolution of the larger cortex. That is human beings lead on the scale closely followed by dolphins. However, the argument progresses as it diminishes at smaller scales with some creature being disproportionally placed high on the list. Other topics highlighted include the evolution of the brain, the evolutionary purpose of sleep, demonstration of sign language abilities, and the accuracy of fear in humanity. The book borrows the concept of understanding the early struggle with fear in the face of reptiles. Numerous attributes are used to explain the subject in addition to speculations of the impact that some devices would have on us in the nearest future.
Tracing Human Intelligence
The book is modest and takes us through a speculative ride in human intelligence. The data in this work starts from the moment when we were the size of a bacteria and is evaluated from there. We are taken through a traversal of all hominids and maintaining that we aren't distant from the apes in the trees. It's evident in the quote, "and after we returned to the Savannah and abandoned the trees, did we long for those great graceful leaps and ecstatic moments of weightlessness in the shaft of sunlight of the forest roof (Sagan 140)?" Sagan confidently demonstrates that the intellectual advancement in technology is just a progression of our ape legacy. He gives credit to researchers when a need arises and shows his prowess in mapping the entire universe's evolution to a single calendar event and explains evolution.
The Cosmic Calendar
The cosmic calendar is vivid in the book from his well-known production "Cosmos." A description of molecular hereditary is given and proposes a quantitative evaluation of the whole mutation process and the relation between brain size and behavioral attributes. Consequently, it results in fetal development and the nervous and brain structure. The main idea put across is that the brain is composed of three segments that operate independently and at cross-purpose. The functionality of the brain is related to left-right hemisphere separation to the tenets of Freudian psychotherapy. A speculation is further advanced, that in the future as computers continue getting better, a huge proportion of our intelligence and knowledge would depend on close unison with them.
Evolving Intelligence
Being interested in evolution, various parts of the book were amazing and a real open up to my intellect. Evolution of extra-genetic intelligence together with extra-somatic intelligence in humanity, nature of "reptile" instincts buried in our regions, and the clash between left and right neocortex and each one's purpose proved exciting. For quite some time, I searched for clues to determine whether rationality is more vital than emotionality. The book provides a clear explanation of the quick and fast evolution of our brain's emotional part than the rational one. The difference between us and other animals is the evolution of neocortex with the rational side of thought. The position provides clarity on the future of brain development and whether there would be detachment to enable the realization of an advanced brain (Gibson 20).
Errors and Critiques
Despite the efforts and success to defend evolutionary evidence with scientific validation, some errors occurred in the process. An example is the rate at which the brain processes information at its peak. A matter of fact is that visual apperception takes place more rapidly. However, the author was estimating the rate at which visual memory can recall accurately. The other error is when fish are considered as invertebrates. He says, "with a few unimportant exceptions, the hereditary nucleic acid is always the molecule called DNA (Sagan 21)." The exceptions are named and proceed to imply that life on Earth is dependent on DNA. Sagan doesn't shy away from any issue and lays down his thoughts all geared towards discrediting some propagated scientific aspects.
Conclusion
In conclusion, Sagan does an excellent job in trying to clarify the evolution of human intelligence and the interrelated events. The book is a must-read for those interested in gaining knowledge in different fields and backgrounds, such as neuroscience, cognition, and development. Other human events are clear, and he maintains a consistent writing style that is catchy, simple, and doesn't put the readers in a bored mood. In the last chapters, he condemns false irrational ideas that are proclaimed as being scientific and labels them as "soft science" and pseudo-science (Sagan 200).
Works Cited
Sagan, Carl. Dragons of Eden: Speculations on the Evolution of Human Intelligence. Ballantine Books, 2012.
Gibson, Kathleen R. “Evolution of Human Intelligence: The Roles of Brain Size and Mental Construction.” Brain, Behavior and Evolution, vol. 59, no. 1-2, 2002, pp. 10-20.
