A Natural History Of Ourselves

Title: A Natural History Of Ourselves

Author: Hannah Holmes

Publisher: Atlantic Books, London 2010 (First published 2008)

ISBN: 978-1-84887-040-6

Pages: 362

Hannah Holmes is a delightful author who effortlessly scores the punches. She is the author of Suburban Safari and The Secret Life of Dust. An early life in the family of biologists had moulded the author for sharp observation and keen analysis of animals and yes, humans too. Modern man is just another animal in a biologist’s view, with little difference in the prime necessities of hard life, those of finding food, living in shelters, obtaining safely from predators and reproducing so that our genes find self expression long, long after we had gone from the face of the earth. This book is a study of humans, just like we would catalog an animal and pigeon-hole it according to several aspects which demand attention. The physical, mental, social and environmental aspects of human animal and its interactions with the outside world are examined in threadbare detail, filling in interesting details along the way. As the Boston Globe remarked, it is ”delightfully funny, though not so comical that we fail to appreciate how much we’re learning”.

The book begins with a general survey of human frame and muses about the evolutionary pathways through which it came into being. The author takes special care to use the original zoological lexicon in naming conventions, hair becomes fur, home changes to shelter, spouse transforms to mate and so on. Human hair gradually faded on the transition from hominids to adapt to the warm climate of African savannas. Still, we have lots of hair on the head, which might have been a modification to shield the ever increasing brain from so much heat poured down by the sun, which would fry it at 42 deg C (107.6 deg F). Humans are also the most sturdy long distance runners, though not record-setting in the matter of speed. We can regularly do tens of kilometers in a day, without even thinking about it twice. Horses don’t come near us, in covering long distances in one go.

The author, while analysing the human features, set before herself the image of herself in a mirror. The musings about the purpose and nature of each appendage in the human frame (!) is humorous in the extreme, though not exactly pampering to the sensitivities with religious prejudices. The deeply religious or opinionated readers may also skip the chapters on reproduction, if they still want to retain a virtuous assessment of the author. Humans reached the present pinnacle of evolution thanks to our brains, which is huge, compared to our frame. It consumes 20% of the total energy absorbed by the body. However, its size – absolute as well as proportional – is not the biggest among other creatures. Humming bird and Central American squirrel monkey have the largest ratio, while elephants and whales take the prize in the case of absolute size. Social animals need larger brains and the author proposes the throwing ape theory, that states that brain size boomed as an evolutionary pressure in the case of apes which developed a technique of spear throwing for hunting.

The book also includes some surprisingly simple, yet astute observations on the human body. Males, who throng with testosterone, have the ring fingers in their right hands longer than the index finger. For females, the second finger is either longer or at least as long as the fourth. Palmists, blubbering for their livelihood have not even had the power of observing this simple fact, which is made evident everytime their clients open the palm! Such is the ridiculousness of pseudo-sciences which produce streams of nonsensical arguments, yet fail to find the conspicuous stone at the bottom.

Human senses are crowned by sight. We boast of excellent colour and 3-D vision which is unique, barring some bird species. The cone cells in our retinas are tuned to detect three pigment types (in the red, blue and green areas of the spectrum), while some birds have cones tuned to five areas of the spectrum. We can only imagine the richness of colours they perceive. At the same time, dogs and other animals have only slightly better than monochromatic vision. Another amazing feature is the humans’ propensity to live anywhere around the globe. Without fire and clothing, though, we are limited to the tropics. Physiology has evolved over eons to acclimatize a person to a particular clime, without too much effort. Humans also adapted to wide ranging diet. Isotopic studies on tooth fossils of Lucy (australopithecus afarensis), our oldest ancestor, found traces of C4 plants (grasses, mainly) and C3 plants (fruits, broad leaves and roots). This indicates that our great-great-grand mother enjoyed a diet of meat and vegetables, the same as we do at present, though slightly differing in the matter of preparation! The wide diet reduced pressure on the digestive system and tooth sizes reduced.

Trying to hybridize humans with another species was always and intriguing activity, which was reportedly tried by Josef Stalin, the communist dictator of Russia in the 20^th century. He wanted to produce fierce warriors, half-human and half-ape who could be effectively utilized in his quest for spreading his venomous philosophy around the globe. Ilya Ivanov, a reputed scientist, artificially inseminated chimps with human semen, but the result turned out to be negative. Confusion reigns in the complimentary case, that of fertilizing human egg with chimpanzee sperms. It is said that the chimps in the experiment died due to disease during that time and the trial was abandoned, as the author says!

Humans have taken over the environment in every way possible and have almost eliminated their predators from the face of the earth. This can have unexpected reactions too, as evidenced by the spread of Lyme disease when gray wolves were eliminated from North American rural landscape. The disease is spread by deer ticks, whose population skyrocketed when their natural predators, the wolves were driven to extinction. A check on their numbers was exercised by rural human population who regularly ate them. When urbanization sprang and rural numbers dwindled, deers again increased without bounds, helping to spread the disease.

As mentioned earlier, the book is charmingly attractive like its author and demands great attention to the book as well as the side issues. Lots of interesting phenomena like Raynaud’s phenomenon, McGurts Effect are mentioned, without spelling out the details. The readers will be driven to research further on these topics on the Net. The book thereby serves its purpose to kindle a flame of enquiry in receptive minds. The full alphabet list (well, almost!) given in p.179 is the definite proof that humans are omnivores. The list includes “acorn, ant, artichoke, barley, bean, beetle, cicada, coffee, cow, date, daylily, dolphin, edamame, eel, egg, fennel, fern, fungus, garlic, goat, Gouda, haddock, hare, horseradish, ikura, Irish moss, iroko, jackfruit, jaguar, jicama, kamut, kangaroo, kiwi, lark, lemon, lentil, mango, mouse, mustard, nasturtium, nectarine, needlefish, obnion, opossum, owl, pansy, papaya, paprika, quahog, quince, quinoa, rat, rhinoceros, Roquefort, shark, sheep, sumac, tamarind, tequila, thistle, ugli fruit, uinta chipmunk, umi, vanilla, Velveeta, vicuna, walnut, whale, wine, yak, yeast, yucca, za’atar, zebu and zucchini”. A item with the letter ‘X’ would complete the list and I am in search of it!

There are nothing much to point out on the down side. In p. 174, the author states that nature abhors waste, to press home her point that human female releases only one egg at a time for fertilization. This assertion rattles with reality. In the case of sperm and pollen, nature produces it in copious quantities, though only one of them has the right to mate in a practical setting. In another section on speculating on the origins of the food species, it is stated that hot and cold pepper was originated in Central America, instead of India. This point is strongly suspected to be false.

Apart from these minor issues, the book is a pleasure to go through and any reader on popular science won’t want to miss this one, for sure. The book is highly recommended.

Rating: 4 Star