Title: Remarkable Creatures
Author: Sean Carroll
Publisher: Quercus 2009 (First)
ISBN: 978-1-84724-798-8
Pages: 284
Another instant hit from the reputed author on evolution. Carroll’s Making of the Fittest (reviewed earlier in this blog), was a great effort to bring evolution palatable to ordinary readers, many of whom would have undoubtedly sought to read further books on the topic – such being the authenticity and attraction of the book. In the present title, Carroll brings out the toil and perseverance behind the discovery and elucidation of original ideas when the protagonists went on long travels to little known places infested with hostile climate, people or fauna. Some of the dramatic adventures and important discoveries which turned the world on its head are catalogued in these pages. The quest for knowledge began in the early 19th century and has continued ever since. Beginning from the origin of life and appearance of early life forms, the search extended to the origin of humans and his place in the evolutionary tree. Alexander von Humboldt, whose epic journey to South America began it all, was not harbouring any revolutionary concepts at all, he was content with accepting the dogmatic proposition that every creature or object has a creator and the world is a harmonious entity, changing little by little in carefully orchestrated steps. The thread was taken over by his successors, Darwin being the most prominent among them, and extended to such dizzying heights as to propose the theory of evolution, common origin of humans in Africa and ruling out the Neanderthal ancestry of modern people by microbiological means.
Humboldt explored South America over a 5-year period from 1799 to 1804. His memoirs raised the urge for exploration in other naturalists to follow in his wake. Charles Darwin, Alfred Wallace and Walter Henry Bates were the most noted among them. Humboldt only observed the features of the virgin landscape and fauna without theorizing. Darwin completed his famous journey around the over five years (1831-36), the germ of evolution growing in him. Being a member of the elite, he was nervous to voice his theories in public who would no doubt treat it as heresy, Darwin was hesitant for 23 years before giving vent to his true feelings. Though the world was agreeable to the hypothesis of special creation (each species of creatures created separately to fill a niche), the extinctions of species like dinosaurs made difficulties. How can one of the God’s creations go extinct? Darwin’s final decision to publish his work was in no small measure prompted by the work of Wallace, who was researching the Malay peninsula along similar lines. It was Wallace who coined the term natural selection, and sent his work to Darwin for onward transmission and publication. Lyell, the eminent geologist knew what Darwin was doing and published both of the works simultaneously in 1859. Walter Bates observed Darwin’s ideas in action in nature, particularly on the mimetic patterns in different species of butterflies, termed Batesian mimicry. Another Dutch man, Eugene Dubois explored the forests of Java to bring to light the partial remains of a hominid, called Java man.
The second part of the book deals with the discoveries related to evolution of lesser life forms. Charles Doolittle Walcott, who later rose to become director of the United States Geological Survey from very humble beginnings without any college education scoured the Canadian Rockies in the beginning of 20th century and yielded abundant fossils of creatures from rock strata of the Cambrian era. A huge number of life forms suddenly appeared during this era in fossil record around 540 million years ago, and is also called Cambrian explosion. This event is also termed the big bang of biology. Such swelling in the number of life forms, raised claims of creation in that period and caused much unrest for Darwin. However, earlier life forms were eventually found beneath the layers. Scientists speculate the dramatic rise in the level of atmospheric oxygen around this time which caused the boom. Explorers were also interested in unearthing dinosaur fossils in the 20th century. Roy Chapman Andrews who once swept the floors of the Natural History Museum in New York organised massive field work in the Gobi desert in Inner Mongolia and obtained dinosaur eggs and mammal fossils coterminous with dinosaurs. This ended the speculation whether mammals had lived alongside the giant reptiles.
In the 1970s, Walter and Luis Alvarez, the father-son duo’s discovery of K-T boundary (the distinctive clay line marking the end of cretaceous and beginning of tertiary periods) proposed plausible suggestions for the extermination of dinosaurs. Alvarez was forced to postulate extraterrestrial origin for the catastrophe, from the excess iridium levels in the clay boundary all over the world. Impact of an asteroid was concluded as the likely reason, when a 180-km dia crater was found near Chicxulub in Mexico. This single event was considered to mark the end of the mesozoic era. Following on the line of dinosaurs, John Ostrom found evidence from fossils in Montana, to argue that birds were a form of dinosaurs. His discoveries were later dramatized in Michael Crichton’s epic science fiction novel, Jurassic Park. Deinonychus was turned out to be one of the transitional forms implied in the theory of evolution. Lack of fossil evidence for transitional forms was used to ridicule evolutionary theory by creationists. Neil Shubin and his team investigated the sedementary layer in Ellesmere Island of the Canadian Arctic and discovered the fossils of Tiktaalik, which is a transitional form between fish and terapods.
The third part of the book covers human evolution and intermediate forms. Louis and Mary Leakey explored East Africa and numerous fossils of hominids and their tools were found. Evolutionary Biology, when it turned its attention to the origin of humans, found great admirers and followers even from other branches of science. Linus Pauling, who is the only person to be awarded two unshared Nobels (for chemistry and peace) was attracted to human evolution and established a method of estimating the time period at which two seemingly different species split up from a common ancestor. Along with Emile Zuckerkandl, Pauling devised a way for calculating the time by counting the differences in protein chains, particularly hemoglobin. This was later fully developed by Allan Wilson and Vincent Sarich. According to their classification, humans and apes shared the common ancestor till as late as five million years ago. Search for hominid forms brought to light the independent species of humans, called Neanderthal men. Svante Paabo analysed mitochondrial DNA from Neanderthal bones and conclusively proved that they are not related to modern humans. Much work still needs to be done in this field.
The book is excellent to read and lucid beyond comparison. The author righly summarizes the work in the afterword and surmises what follows next in mankind’s onward journey. If the last 150 years was dedicated to the search for the origins of life on earth, the next century may well be dedicated to finding life elsewhere in the universe. Astronomical explorations, in the form of space-based telescopes have already been trained on these exoplanets which may harbour conditions feasible for life. Discoverers of the calibre of Humboldt and Darwin may still be found in today’s human societies who would be more than willing to dedicate their productive careers in the search for attainment of knowledge, of seeing something not seen before, of describing something which are only dreamt of, so far. The book presents a seemingly unbroken thread through the chapters and parts through which it is divided. Carroll commands and obtains the unbroken attention of the reader.
One of the two points which can be levelled against is that the chapters become progressively less absorbing as it moves from the likes of Darwin to modern explorers. This might not be the author’s fault in fact, as the glamour of following the footsteps of stalwarts like Charles Darwin is not replicated for scientists who are still living among us. Another drawback is the feeling that the title has not done justice to the theme of the book, which is about the pioneering explorers and their work, rather than the remarkable creatures they have put before the world.
The book is highly recommended.
Rating: 4 Star
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