Rats, Lice, and History

Our book today is Hans Zinsser's Rats, Lice and History, and it completes the little popular-science triptych we've been indulging in here at Stevereads (an arbitrary stopping-point, since we could, otherwise, cover really, really entertaining popular science books literally every day for the next year without running out of wonderful titles). Zinsser, a native New Yorker who spend his life as an increasingly-famous bacteriologist, wrote this, the best-known of his books, in 1935, which makes it a good deal older than our other two titles, but it's the best of the three, a deep and intensely satisfying study with numerous digressions.

Zinsser sets his task right from the start: to write a biography. But he himself faithfully catalogues his obstacles:

There will be no prenatal influences; no Oedipus or mother complexes; no early love affairs or later infidelities; no perversions, urges, or maladjustments ... We shall have no gossip to help us, no personal letters which there was no time to burn. We cannot count upon the reclame of a libel suit barely averted, or of scandals deftly hinted at. We have not even the comfort of preceding biographers and essayists whom we can copy, paraphrase, or refute. Indeed, we are quite stripped of the sauces, spices, and dressings by which biographers can usually make poets and scientists into quite ordinary and often objectionable people; by which they can divert attention from the work of a man to his petty or perhaps vicious habits; by which they can create a hero out of a successful commercial highbinder; by which they can smother public guilt by domestic virtue, or direct interest from the best and lasting accomplishments of their subject to the utterly unimportant private matters of which he was ashamed.

The habitue of biographies will ask himself how, without these indispensable accessories of the biographical tradesman, we can dare to enter this field. The answer is a simple one: the subject of our biography is a disease.

That disease is typhus, whose global path of destruction Zinsser recounts from earliest times (and all of whose vectors - through lice, through the fleas of infected mice and rats, and through infected nightcrawlers - are covered by his narrative reach) to the present, when the West made huge strides against the disease (many of those strides were made by Zinsser himself, or colleagues he inspired and helped). Typhus is a hugely successful family of bacteria, hardy and opportunistic, most widespread in conditions of abysmal sanitation - conditions that, in a world full of the squalor and waste of human cruelty, are not hard to find. The disease has been rampant in times of war, famine, and concentration camps since the dawn of mankind. It's easily treatable with antibiotics, but the most formidable foe it ever faced was likely Hans Zinsser.




He wears it all lightly, as you could tell from the above excerpt (as is also abundantly evident from that excerpt, with Zinsser's book we are dealing with a level of prose many orders of magnitude more advanced than either Stephen Jay Gould or Carl Sagan - as either one of them would have been quick to concede). Rats, Lice and History is immensely learned and informative, but it is also very funny, very clever, and often very playful. These things are not antithetical to the well-stocked mind, nor are they detrimental to a high purpose. Zinsser has fun throughout his book, and he tries his best to share that fun with his readers (and he's had readers! This book has been through countless editions).

In writing his biography, and especially in dealing with something at once as complex and as simple as bacteria (they are hard to understand, although not nearly so hard as viruses), Zinsser tries to start with the broadest possible canvas: what is life itself? How do we define it? And where did it come from:

Did life originate spontaneously by such progressively complex associations of matter through enzymes - unformed, regulated intermediaries, capable of building up and expending energy? Or did it come to our earth from elsewhere - cosmically, - in which case it would have had to possess the capacity of resisting, without destruction, exposure to temperatures ranging from absolute zero to incandescence. We cannot deny these possibilities, but we have no clue to either. We are beginning to know that all the processes which take place in living beings are governed - though with more complexity - by the same physiochemical laws which govern the reactions in dead chemical systems. Yet this purely mechanistic understanding is insufficient for the final answer, and vitalism is reborn again and again to bridge the gap.

(Zinsser's speculation, though gripping, is in this case fanciful: no living organism could possibly survive the trauma of planetary entry - all Earth life is certainly Earth-originated, although the rest of his ruminations on the flickering boundaries between life and non-life are spot-on)

A hardy disease that thrives on squalor - it's easy to see why typhus in all its various forms would have such a successful life among mankind. That it thrived even in comparatively modern times is well-known and deplorable; Zinsser extensively catalogs its domination of more ancient eras as well:

In earlier ages, pestilences were mysterious visitations, expressions of the wrath of higher powers which came out of a dark nowhere, pitiless, dreadful, and inescapable. In their terror and ignorance, men did the very things which increased death rates and aggravated calamity. They fled from towns and villages, but death mysteriously traveled along with them.

Centuries later, things have scarcely improved:

The Thirty Years' War was the most gigantic experiment in epidemiology to which mankind has ever been subjected. Europe, as we have seen, was a spot map of constant small outbreaks of every conceivable infectious disease; and through this area, for a little over twenty-nine years, armies marched and countermarched, and disbanded soldiers, fugitives, and deserters vagabonded far and wide. Famines resulted and populations wandered in fugitive hordes toward food and protection. Wherever men traveled, disease followed them.

In a withering footnote, one of many swipes Zinsser takes at the carnage of the First World War, he writes:

Nature sets up her experiments of epidemiology in times of war and famine, and when, as in the wars of the late nineteenth and twentieth century, these dreadful experiments can be observed by a competent medical profession, much of value to mankind may be learned. It can well be said that nobody won the last war except the medical sciences. The profit was not worth the loss, but the increase in sanitary and medical knowledge was the sole determinable gain for mankind in an otherwise utterly disastrous catastrophe.

It's precisely this tone, this perfect balance between the frustration of a scientist and the optimism of a humanist, that gives Rats, Lice and History its perennial appeal, and it's a tone Zinsser maintains all the way to the book's conclusion, which is caustic, cautionary, and celebratory all at the same time:

Typhus is not dead. It will live on for centuries, it it will continue to break into the open whenever human stupidity and brutality give it a chance, as most likely they occasionally will. But its freedom of action is being restricted, and more and more it will be confined, like other savage creatures, in the zoological gardens of controlled diseases.

The happy day Zinsser envisioned, when all strains of typhus would be safely confined in laboratories, is as far off today as it was when he first wrote his book; the diseases abound in the modern world, and several modern countries (most certainly including the United States) have toyed with the possibility of developing 'weapons-grade' typhus for use as a biological weapon (it has a satisfyingly high mortality rate if untreated, but it can't readily be spread human-to-human). Sadly, the stupidity and brutality of humanity noted by Zinsser, also seem incapable of eradication. We can only hope a bell-note wonderful book like Rats, Lice and History survives as well, infecting everybody it touches.

The Panda's Thumb

Our book today is The Panda's Thumb, the 1980 collection of natural history essays by Stephen Jay Gould, who published them all originally in his "This View of Life" column for Natural History magazine, back when that publication was (largely due to his presence month after month) still worth reading.

Gould was an evolutionary biologist, an entomologist, an anthropological theorist, and, more than any of those things (and the half-dozen or so other interdisciplinary hats he wore from time to time), a natural-born teacher, able to summarize and jazzercise virtually any subject, no matter how abstruse, into eight or ten jaunty, inviting pages anybody on Earth would enjoy reading. This is not a trait often found in scientists, and it is not to be scorned (the ones who do scorn it, both inside and outside the scientific world, are invariably the ones who can't do it, or who are too lily-livered to try). Given a small lead-time and no more reference-works than could be found in his overstuffed personal library, Gould could write an essay on, say, neotony, that you could not only hand to your fundamentalist grandmother but that would leave her wanting more. And he did it all amiably, without ever striking a strident note.

This last is all the more remarkable when viewed alongside his peers, some of whom could be very strident indeed. The mind naturally turns to Richard Dawkins, who shared an intellectually heated - and temporarily famous - exchange of letters with Gould in the pages of The New York Review of Books years ago - letters in which Gould comes off the better. Dawkins' 'selfish gene' idea of gene-dominated evolutionary drives never met with much enthusiasm from Gould, as he writes at one point in The Panda's Thumb:

Still, I find a fatal flaw in Dakwins's attack from below. No matter how much power Dawkins wishes to assign to genes, there is one thing that he cannot give them - direct visibility to natural selection. Selection simply cannot see genes and pick among them directly. It must use bodies as an intermediary. A gene is a bit of DNA hidden within a cell. Selection views bodies. It favors some bodies because they are stronger, better insulated, earlier in their sexual maturation, fiercer in combat, or more beautiful to behold.

If, in favoring a stronger body, selection acted directly upon a gene for strength, then Dawkins might be vindicated. If bodies were unambiguous maps of their genes, then battling bits of DNA would display their color externally and selection might act upon them directly. But bodies are no such thing.

Gould will be known in the science-history books mainly as the co-creator (along with Niles Eldredge)(who, with a colleague like Gould, ought to legally change his first name to "along with") of the idea of punctuated equilibrium: the concept that the process of evolution by natural selection is far from the stately, Lyellian progression tradition had made it out to be:

A new species can arise when a small segment of the ancestral population is isolated at the periphery of the ancestral range. Large, stable central populations exert a strong homogenizing influence. New and favorable mutations are diluted by the sheer bulk of the population through which they must spread. They must build slowly in frequency, but changing environments usually cancel their selective value long before they reach fixation. Thus, phyletic transformation in large populations should be very rare - as the fossil record proclaims.

Gradualism, the belief that all change must be smooth, slow, and steady, was never read from the rocks. It represented a common cultural bias, in part a response of nineteenth-century liberalism to a world in revolution. But it continues to color our supposedly objective reading of life's history.

But the history of life, as I read it, is a series of stable states, punctuated at rare intervals by major events that occur with great rapidity and help to establish the next stable era. Prokaryotes ruled the earth for three billion years until the Cambrian explosion, when most major designs of multicellular life appeared within ten million years. Some 375 million years later, about half the families of invertebrates became extinct within a few million years. The earth's history may be modelled as a series of occasional pulses, driving recalcitrant systems from one stable state to the next.



Gould's essays (The Panda's Thumb contains such classics as "Piltdown Revisited," "Were Dinosaurs dumb?" and the glowingly inimitable "A Biological Homage to Mickey Mouse") dance happily from one subject to the next, as Gould's own interests did (baseball and Gilbert & Sullivan get equal - and equally loving - attention). And always he returns to the big picture, the broader canvas on which the forces of evolution work and one which he tried to think (and succeeded more often than most mortals ever come close):

The best illustration of dinosaurian capability may well be the fact most often cited against them - their demise. Extinction, for most people, carries many of the connotations attributed to sex not so long ago - a rather disreputable business, frequent in occurence, but not to anyone's credit, and certainly not to be discussed in proper circles. But, like sex, extinction is an ineluctable part of life. It is the ultimate fate of all species, not the lot of unfortunate and ill-designed creatures. It is no sign of failure.

The remarkable thing about dinosaurs is not that they became extinct but that they dominated the earth for so long. Dinosaurs held sway for 100 million years while mammals, all the while, lived as small animals in the interstices of their world. After 70 millions years on top, we mammals have an excellent track record and good prospects for the future, but we have yet to display the staying power of dinosaurs.

It's not given to science-writers like Gould to have much staying power at all, and slowly, one by one, his many delightful titles will proceed out of print. But the books themselves will always lurk in the interstices, available for your curious mind. The man himself died in 2002, far too early, but echo of his many enthusiasms can be found in books like The Panda's Thumb, from Marathon to Waterloo in order categorical.

The Dragons of Eden

Our book today is Carl Sagan's wise and witty little 1977 masterpiece, The Dragons of Eden, which spent a gratifying number of weeks on the bestseller lists and delighted a very large number of readers who might otherwise have considered themselves the furthest thing in the world from being science readers.

The reason for the appeal is that Sagan was a masterful popularizer (the late 60s and 70s were a golden age for such popularizers, for reasons that remain slightly obscure), and in none of his books is this more evident than in The Dragons of Eden, whose nine chapters cover in enthusiastic and illuminating detail many of the highways and byways of what it means to be human. When we here at Stevereads read it (an advance copy was sent to us by Asimov, as always craving our attention), we felt as if we were once again in the presence of Pliny the Elder, hearing of marvels, seeing everything entirely anew.

Every separate chapter in The Dragons of Eden is a self-contained masterpiece (honed to perfection by test-runs on countless student audiences throughout the years), an essay of nearly incantatory elegance and power. "The Brain and the Chariot" and especially "Tales of Dim Eden" are marvelous probings of the soft workings of the human brain, where many of the mysteries Sagan confronts are still mysteries today. In the chapter "Genes and Brains," the digression on hybrids affords our author an irresistible chance for some fun:

In earlier times it was widely held that offspring could be produced by crosses between extremely different organisms. The Minotaur whom Theseus slew was said to be the result of a mating between a bull and a woman. And the Roman historian Pliny suggested that the ostrich, then newly discovered, was the result of a cross between a giraffe and a gnat. (It would, I suppose, have to be a female giraffe and a male gnat.) In practice there must be many such crosses which have not been attempted because of a certain understandable lack of motivation.

Our nominee for single best chapter is "The Abstraction of Beasts," in which Sagan explores the subject of animal cognition with a sensitivity both rare and pleasing to find. Here he deals with Washoe the chimp learning sign language and opening up to scientist an entire new world, in which mankind's nearest genetic relative could directly express sadness, joy, creativity, grief, embarrassment, and linguistic creativity:

Washoe was observed "reading" a magazine - i.e. slowly turning the pages, peering intently at the pictures, and making, to no one in particular, an appropriate sign, such as "cat" when viewing a photograph of a tiger, and "drink" when examining a Vermouth advertisement.

Sagan wrote his book when the Western world was on the cusp of enormous technological change, far greater change than even science's most talented visionaries (and he was science's most talented visionary) could guess. As he correctly intuited, such change can be frightening (The Dragons of Eden is rife with great quotations from other writers, and one of the best deals with the very subject - Alfred North Whitehead: "It is the business of the future to be dangerous ... the major advances in civilization are processes that all but wreck the societies in which they occur"), but likewise these changes - and the fascinating forces behind them - could have no better, no more welcoming emissary than Carl Sagan.


His secret was wonder, and despite the generous lampooning he received when American television audience's got a glimpse of that trait in Sagan's mini-series Cosmos, it was real; he never stopped feeling the thrill of being a free mind in a world of wonders.

Perfect case in point: years ago he and I were leaving the same lecture (James Van Allen, as always ending his talk with a quick fusillade of dazzling ideas), emerging into a crossroads crammed with cars and trucks, all honking their horns in a heavy downpour. We shared a rough geographical proximity, so we agreed to split a cab. Moments later we were logjammed, rain pouring down, horns honking everywhere, and the cab driver made some grousing remark about the traffic jam.

Sagan immediately started talking about the beauty of it all, about the sheer statistical rarity of pure drinking water falling free out of the sky, about the tremendously complex harmonics the falling rain made on the various car and truck roofs, how the wind and the thickness of the roof metals and the horns and the echoes bouncing back and forth were nothing less than an acoustic miracle, a fantastic riff-session that was totally unique to this moment and would never come again.

Impulsively, he rolled down his window (this was back when you could still do that in a cab, at least in the trusting Midwest), letting in gusts of water. Turning his face up into the rain, smiling that weird, beatific smile of his, he said, "This isn't a traffic jam; it's a symphony."

Perhaps neither I nor that cab driver could quite access the sheer wonder he was feeling at that moment, but we knew enough to shut our mouths while we were seeing it.

The Dragons of Eden is completely filled with that same wonder, here preserved for all of you to read anytime you like, without your copy of the TLS getting soaked. The book's print run was enormous; you'll find a copy in every thrift shop and library sale in the country, so don't cheat yourself of an opportunity to be science reader!