Around midway, or even a little earlier during the Industrial Revolution, historically high death rates from TB began to go down even while the number of deaths continued to rise. Redeker [58] reported that TB death rates in London peaked at 950/100,000 as early as 1755. Kraus [59], however, states that mortality from “consumption,” also in London, was cataloged at 1,121/100,000 during 1771–1780, after which it declined to 716/100,000 during 1801–1810. The explanation – for the decrease in death rates while the number of deaths rose – was the ongoing, striking increase in the size of the English population during that period, which included more and more new professionals, doctors, lawyers, bankers, business-men, and entrepreneurs of all sorts. “Thus was born the English middle class” [57], an increasingly important group that was much less vulnerable compared to their TB-stricken predecessors.
Two related scientific articles tackle the important question of whether there were individuals or families that stood out as being protected from TB-induced disease and death during the 17th to 19th centuries, when practically everyone was infected by tubercle bacilli and mortality from active disease hovered around 50% or even higher. Lipsitch and Sousa [60] ask whether the presence and magnitude of natural selection contributed to the development of resistance to TB, which had been proposed as a factor affecting the historical decline in TB, before chemotherapy was introduced. The authors concluded that natural selection by deaths from pulmonary TB cannot account for the 150-year-long ongoing reduction in TB detected in Europeans and their descendants, except during both WWI and WWII, the latter of which was recorded just before the arrival of anti-TB treatment.
Thanks to the exceptional reduction in death rates from TB chemotherapy after the mid-20th century and onwards, Stead [61] showed a significant difference in the percentage of persons who developed positive tuberculin skin test reactions following exposure to severe outbreaks of TB in white communities compared with those in African-American communities. Stead hypothesized that everyone infected by M. tuberculosis should develop a positive tuberculin reaction, and if an individual remained negative, it implied the presence of genetically determined innate resistance to TB in both them and their ancestors.
Both of these investigations are of interest, but fail to completely explain what actually caused the historically conspicuous and lengthy decline in TB deaths rates.
Evolution of Warfare
Wars began long before the beginning of recorded history, but the subject has been written about from every conceivable angle. After his retirement, Carl von Clausewitz [62], a Prussian veteran of Napoleonic and other wars, wrote a famous book, On War, in which he said, among other notable quotations, “War is merely a continuation of politics by other means – not merely a political act, but a real political instrument.” Politics unquestionably played an important role in many wars, but there are additional reasons why armed men kill innocent people. Clausewitz’s wars were “civilized wars,” fought by officers and gentlemen who fight by rules and who are governed by military discipline and ethical principles. Keegan [63], however, adds that there have also been “non-civilized wars” that have employed atypical military techniques featuring exceptional violence and death. More than a few armies have concentrated on looting, raping, and pillaging, intensified by deliberate cruelty and excessive butchery. A legendary example was Genghis Kahn [64], who created the world’s largest-ever empire in Northeast Asia in the 13th–14th centuries. Kahn specialized in annihilating Mongol tribes using a combination of advanced military tactics and merciless brutality; on one occasion, having defeated an army of Tatars along with their captured chiefs, he had all the chiefs boiled alive.
As stated earlier in this chapter, many experts agreed on the fact that “at least H. sapiens, and possibly earlier prehumans, possess innate, genetically programmed lethal violence.” Genes may contribute, but warfare takes abundant forces, leadership, and considerable resources. Nevertheless, without that apparent, crucial genetic underpinning, it is certainly possible that wars would not be such an inviolable, practically endless feature of human existence.
Of course, the issue is debatable and controversial, but we might someday learn the correct answer. A remarkably new gene-editing technique called CRISPR allows research scientists to remove and substitute pin-pointed genes in experimental animal genomes. Ethical concerns have retarded use of the method in disordered human genomes (e.g., in sickle cell anemia, Huntington disease, and other dominant genetic disorders), but in theory it is possible. Deleting the culprit war-enhancing genes – if present – would solve the genetic role in warfare and contribute to everlasting peace.
Prehistory
Like virtually all vertebrate animals, interpersonal violence has been an integral, mostly spontaneous, component of ordinary hunter-gatherer’s prehistoric life. It would be interesting to know how the group’s interpersonal dynamics played out, but the band’s survival must have greatly depended on all members’ participation and teamwork. And it makes perfect sense. Presumably, hunter-gatherers functioned in small bands of 20–25 members and had considerable vacant space to forage in. If a hunter-gatherer band recognized that a rival gathering was in the vicinity, it seems unlikely that the 2 groups sought to kill everyone in sight; instead, they usually carefully avoided each other: that proved to be safer and healthier and, as far as we know, it probably helped everyone to stay alive and preserve the size of their bands.
Two rival hypotheses – one short and the other long – differ chiefly in the duration and intensity of late-Paleolithic, early-Holocene savagery, leading up to actual acts of warfare. But the idea of having both a short and a long incubation period leading to the buildup of warfare accommodates the fact that, first, the great majority of H. sapiens residing in Europe, India and surrounding countries, and throughout Asia made the successful transition during the early Holocene epoch from the foraging life of hunter-gatherers to one of farming and animal domestication – with a minimum of violence and practically no warfare [65]. And by contrast, second, several other countries – Australia, South America, North America, together with Paleoamericans and Alaskans, and New Guinea – practiced extreme violence, including the harvesting of scalps, skulls, long-bone trophies, and revenge killings, which lasted in some places until post-colonial years [66]. To summarize, each of the 2 “hypotheses” turns out to provide an apposite explanation for the different time courses of the transition from hunter-gathering to war.
Jericho
A frequently cited clue to the beginnings of warfare