Monkshood

Common Name: Monkshood, Helmet-flower, Wolfsbane, Devil’s Helmet, Aconite – Like many common names, Monkshood is descriptive, emphasizing a feature recognizable as a head covering like a hood or a helmet. Aconite reflects the well-deserved reputation of the plant as a poison and therefore a bane to wolves. Aconite is known as the queen of poisons.

Scientific Name: Aconitum uncinatum – There is little doubt that the generic name Aconitum is taken directly from the Greek word akoniton, but it is not clear what it meant in ancient Greece. By direct translation, konis means “dust”, so a-konis is “without dust.” [1] It has been suggested that the places where the plant grows (like the rocky shores of the Greek archipelago), were literally without dust. The confusion is attributable to the cultural importance (and names) of the plant millennia before historical accounting. Uncinate means bent at the tip like a hook, a direct derivative in English from the Latin (later French) uncinatus.

Potpourri: Monkshood has one of the best descriptive names among flowers. The arched petals that extend over the stamen and stigma complex of the flower’s reproductive organs is similar in form, if not function, to the cowl of the cassock worn by monks to emphasize religious piety and plainness; there is no need for a mnemonic. While the flower is not all that common in North America (except as a garden varietal), it is much more so in the Mediterranean basin, where it rose to prominence in prehistorical accounts due to its use as both a medicinal in small doses and as a deadly poison above a low lethal threshold. Its unusual shape can only have evolved to attract a particular pollinator, as flowers can have no other function that to employ the mobility of animals to transfer the male pollen to the female ovary. The plant itself is spindly, depending on the support of other adjacent plants [2]. This too is a matter of successful evolution, midway between a free-standing shrub and a draped, climbing vine. A smaller, white variant called Trailing Wolfsbane (A. reclinatum) is also found in the southern Appalachians.

Monkshood is a member of the buttercup family (Ranunculaceae) which gives its name to the order Ranunculales, which means small frog in Latin due to the frog-like, or ranine shape, of the type species’ leaves. According to the latest DNA iteration to the three-hundred-year-old (and increasingly obsolete) taxonomy of Linnaeus, the plants of the buttercup order are among the earliest lineages of those with flowers. When, where, and how life emerged from the sea onto the forbidding shores of terra firma is a matter of ongoing conjecture. What is clear is that the encased seed angiosperms came later, eventually evolving the improbable shapes and colors of flowers. This was evident to Darwin, who wrote that “flowers rank amongst the most beautiful productions of nature” and could not have evolved “if insects had not been developed on the face of the earth.” [3] One may conclude that monkshoods evolved vibrant colors and an overhanging petal because that configuration (and possibly scent) drew a specific pollinator that fertilized the plants to which it was attracted and perpetuated the “intelligent design.”

The angiosperms split into two primary clades as they spread across Pangaea in the Cretaceous Period about 130 million years ago. The monocots (single seed leaf or cotyledon) having parallel veins like grasses, orchids, and lilies comprise about one quarter of the angiosperms while the eudicots (formerly dicots) with veined leaves and two cotyledons comprise most of the remainder. [4] The buttercup family was one of the earliest branches of the eudicot clade as diversification increased with dispersal to new habitats. Based on DNA analysis, the order Ranunculales is “sister to all remaining eudicots” [5] This phylogenic analysis is supported by the recent discovery of an intact fossil of a mature eudicot plant that included five stems and one intact flower that appears to have been a type of buttercup. Based on half-life measurements of the radioactive decay of argon and uranium in the surrounding soil, the flower bloomed about 127 million years ago. [6] The buttercups are then among the oldest of all the flowering plants. Their survival through the ages implies an early evolutionary trait that promoted their propagation – like toxins.

Many of the plants of the buttercup family are noted for their poisonous metabolites, even the common buttercup (Ranunculus acris). A popular field guide states “all native species of buttercup contain toxic or otherwise irritating oils and should not be eaten.” [7] However, since plants produce toxins almost certainly to protect against microbial and insect predation, the repurposing of plant toxins as herbal remedies has been common practice since antiquity. An equally popular field guide for medicinal herbs promotes buttercup leaves as “external rubefacient in rheumatism, arthritis, and neuralgia” while in the same breath warning “extremely acrid, causing intense pain and burning in mouth … blisters skin.” Native Americans used a poultice made from buttercup roots to treat abscesses and boils. [8] Monkshood produces the toxin aconite, named for the genus, which has been used as both a deadly poison for killing and a valued pharmaceutical for healing.

Pliny the elder, the storied Roman military commander who died while attempting to rescue victims of the eruption of Mount Vesuvius in 79 AD, provides one of the earliest accounts of aconite in his seminal Natural History. Citing its Homeric mythological origins from the foaming mouth of the three-headed dog Cerberus that guarded the entrance to Hades, he relates that in “countries frequented by the panther, they rub meat with aconite, and if one of those animals should but taste it, its effects are fatal: indeed, were not these means adopted, the country would soon be over-run by them.” But it was equally well established that aconite was also useful as a treatment, pointing out that aconite in mulled wine neutralized the venom of a scorpion bite. Citing in general that “such is the nature of this deadly plant, that it kills man, unless it can find in man something else to kill,” he promotes it as “remarkably useful ingredient in compositions for the eyes.” In anticipation of the Doctrine of Signatures, Pliny praises the “deity who has made to us these numerous revelations for our practical benefit.” [9]

The fall of the Roman Empire to Germanic invaders in the fifth century ushered in the so-called Dark Ages; the repository of knowledge from the Greeks and later the Arabs was largely forgotten until the Renaissance rebirth a thousand years later. The aconite of Monkshood, however, was well known to even the pagan peoples and used mostly as a poison but also as a beneficial herb throughout antiquity. Practices vary from place to place, but it was reportedly used to fatten geese in eastern Europe, as a salad ingredient in Sweden, as a treatment for fever and joint pain in Germany, and as a remedy for the rhematic gout of King Charles IV of Spain. Poisoning was more common, with accounts ranging from killing unwanted people, like “the old men of Ceos, when no longer useful to the state” to poisoning the water supply of enemy states. [10] At the beginning of the modern era in the sixteenth century, the medicinal benefits of Monkshood had been supplanted by the evil of its poison. John Gerard provides an account of “certain ignorant persons” serving up a salad of Wolfsbane in Antwerp resulting in the “cruel” deaths of all patrons with swollen tongues, bulging eyes, and “their wits taken from them.” In conclusion, he notes that “there hath been little heretofore set down about the virtues of aconites.” [11]

Aconite is one of many plant alkaloids, hydrocarbon chemicals produced through evolutionary mutation usually but possibly not always, to enhance survival. The first plant alkaloid was discovered in 1804 by the German chemist Frederich Serturner who extracted a substance from opium poppies which he named morphium, for the Greek god of dreams Morpheus. The term alkaloid was coined in 1819 due to the observation that dissolving one of the chemicals in water yielded an alkaline solution (i.e. PH > 7.0). Over the course of the next half century, strychnine, caffeine, quinine, nicotine, atropine, aconite, and cocaine were identified by chemists, all potent and some poisonous. Aconite became known as the “queen of poisons” because it is fast acting, causing death in less than an hour, and because it was essentially impossible to detect before the development of sophisticated laboratory analysis techniques over the last century. Its reputation as one of the preeminent poisons of antiquity is warranted.

Aconite kills by interrupting the sodium channels that open and close to allow for ionic transport to reset the electrical potential of nerve and heart cells. In one of biochemistry’s more unusual mechanisms, nerve and heart cells must reset after every signal and beat by the exchange of positively charged potassium ions and negatively charged sodium ions. The resetting of the electrical charge, called depolarization, is truly the spark of life. The symptoms of aconite poisoning start with vomiting and diarrhea as the stomach and then the small intestine react to the poison. Once in the blood stream, all sensation gradually ceases, manifest by numbness and ultimately by the inability to breathe exacerbated by heart palpitations. The only question is whether death will ensue by asphyxiation due to paralysis of the diaphragm or cardiac arrest. The effect of aconite on nerves explains why it is also useful as an analgesic. Pain is a product of sensory nerves. Applying aconite in low doses topically alleviates pain. The problem is that the dose level for pain mitigation is not too far removed from the lethal dose.

One of the more interesting criminal cases involving the use of aconite as poison involved a murderer seeking to eliminate the other heirs to an inheritance. Geroge Lamson was betrothed to an orphaned daughter of a wealthy British merchant which made him entitled to her portion of the money, shared with three other siblings. When one of the siblings died, Lamson, in debt due to heroin addiction, realized he could become solvent again by doing away with another. Lamson, who was a physician, purchased a small amount of aconite from a pharmacist, presumably for use as pain medication. He arranged a visit with his nephew Percy at his boarding school, bringing a Scottish Dundee cake laced with aconite to afternoon tea. Percy lost consciousness and died that evening. Suspicion fell on Lamson, who was ultimately convicted based on the injection of a sample of Percy’s urine into a mouse which died in half an hour and due to the testimony of the pharmacist that had sold the aconite to Lamson. He was hung on 28 April 1882 at London’s Wandsworth Prison. [12] According to the “eye for an eye” biblical prescription, a dose of aconite would have been a more just retribution for his crime.

References:

1. Webster’s Third New International Dictionary of the English Language, Unabridged, G. M. Merriam and Company, Chicago, 1971, p. 18

2. Niering, W. and Olmstead, N. National Audubon Society Field Guide to North American Wildflowers Alfred A. Knopf 1998 pp 374-375.

3. Darwin, C. On the Origin of Species, Easton Press Norwalk, Connecticut, 1976, p 165.

4. Wilson, C. and Loomis, W. Botany, Fourth Edition, Holt Rhinehart and Winston, New York, 1957, pp. 274, 373, 571-577.

5. Moore, M. et al “Phylogenetic analysis of 83 plastid genes further resolves the early diversification of eudicots” Proceedings of the National Academy of Scientists, Volume 107 Number 10, 22 February 2010, 99 4623-4628 .https://pmc.ncbi.nlm.nih.gov/articles/PMC2842043/

6. Carpenter, J. “Science Shot, The Oldest Buttercup Yet” Science, 30 March 2011

7.Elias, T. and Dykeman, P. Edible Wild Plants, Sterling Publishing Company, New York. P 262.

8.Duke, J. and Foster, S. Medicinal Plants and Herbs, Houghton Mifflin Co., New York, p 123.

9. Pliny. “Chapter 2. Aconite, Otherwise Called Thelyphonon, Cammaron, Pardalianches, or Scorpio; Four Remedies.”. The Natural History of Pliny, Book XXVII. Translated by Bostock, John; Riley, Henry T. p. 218.

10. Jackson, R. “Notes on the History, Properties, and Uses of Aconitum napellus” The Lancet. 3 May 1856 Volume 67 Number 1705

11. Gerard, John. The Herball or Generall Historie of Plantes (1st ed.) 1597, London: John Norton. P 111-114

12. Bradbury, N. A Taste for Poison, Saint Martin’s Press, New York, 2021, pp 92-116.

Hiking and the Evolution of Homo sapiens

The genus Homo separated from the chimpanzees of the genus Pan about 5 million years ago to become the first and only bipedal ape.

Moving from one place to another on two legs is a matter of some importance to the genus Homo, which separated from the other primates several million years ago as the first and only biped, evolving to Homo erectus. Prior to that, swinging through trees and rambling about on the ground in a knuckle-dragging galumph was de rigueur. We walked before we talked and we talked before we texted. The twentieth century dawned with an uncontrolled experiment that resulted from the industrial revolution of the nineteenth. Earning ones’ daily bread changed from activities of bodily motion and physical work to consumption based on the energy of steam and then oil and gas. We ride where we once walked, and we sit when we once stood. Whether this is sustainable on a global scale with over eight billion people remains to be seen, but there are good reasons to be concerned. On the level of the individual, increasing obesity and the prevalence of chronic metabolic conditions suggest that the experiment with riding and sitting is not going well. Thoreau wrote “I think that I cannot preserve my health and spirits unless I spend four hours a day at least …sauntering through the woods and over the hills and fields, absolutely free from all worldly engagements.” [1] The inner peace that results from a hike in the woods is not coincidence; it is universal and as true now as ever it was.

Walking is a healthful activity, hiking even more so. This has been demonstrated empirically and established according to the scientific principles of the experimental method. It is an activity that is not only innate but deeply gratifying and one that can last a lifetime. It strengthens muscles and joints as a consequence of motions that are entirely natural. While these truths are self-evident, there is more to it than that; Homo sapiens evolved as a bipedal nomad and survived according to fitness. The implication is that the inexorable forces of nature selected the operating system of heart, lungs, arms and legs with all its vascular plumbing and neuron wiring to accomplish the task of moving about on two legs. The last decade has witnessed a renaissance in biology. The understanding of DNA and its role in evolution has established fact where hypothesis once prevailed, profoundly disrupting anthropology formerly based solely on physical characteristics. Neanderthal man (Homo neanderthalensis), once considered our direct ancestor, is now established genetically to be an extinct subspecies with whom modern humans interbred [2]. While there are many twists and turns yet to be discerned in our lineage, it is clear from DNA that humans of the genus Homo separated from chimpanzees of the genus Pan about 5 million years ago (MYA) to become the first and only primate to evolve bipedalism, locomotion on two limbs. While there remains legitimate speculation as to why this occurred, there is no disputation that it did as we exist; cogito ergo sum.

Darwin’s theory of evolution is only a theory in the sense that it cannot be proven by the scientific method of testing with variables and controls. It is not (currently) possible to turn back the clock and conduct experiments in evolutionary forcing factors. The underlying principle of survival is immutable, however, and one can only survive by eating, not being eaten, and reproducing at a rate that increases an extant population; the Darwinian term is “fittest.” What the common ancestor of chimps and humans must have faced was an environment in which an upright posture conveyed survival advantages. Darwin writes in The Descent of Man that “man could not have attained his present dominant position in the world without the use of his hands,” though it is much more likely that this is a result rather than a cause of bipedalism. One might also posit that an upright posture affords a better view, but apes can stand periodically to that same end. Primates had been around for about 30 million years; the profound physical changes of bipedalism must have resulted from factors more fundamental than handiness and height.

Climate is a generic term for the complex forces of wind and water that operate on a scale with global reach, weather is its quotidian result. When combined with the equally perplexing geology of subducting tectonic plates and spreading ocean floors, the task of deducing environmental conditions of the past is daunting. But generalizations are possible; it is relatively clear from the rock record that a series of glacial maxima occurred in the Ice Age or more properly the Pleistocene Epoch that extended from 2.6 MYA to “just recently” – 10,000 years ago. It is equally evident that the earth went through a period of gradual cooling during the Pliocene Epoch that preceded it, coincident with the advent of walking apes. On the African continent, the lush forests of the hotter and wetter Miocene Epoch gradually but inexorably gave way to savannah and the concomitant emergence of grazing herd animals that fed on its grasses. It is of possibly dire consequence that the last time that carbon dioxide levels in the atmosphere exceeded the recently achieved 400 ppm was during this quite warm pre-human epoch [3]. The habitat of the forest ape was diminished with the cooler climate affecting its jungle smorgasbord of nuts and fruits. The savannah beckoned, and the more adventurous and perhaps desperate apes first came down from the trees. The Laetoli bipedal footprints were discovered just south of the Olduvai Gorge in Tanzania by Mary Leakey in 1976. Extensive research has established that they were made by hominids of the species Australopithecus afarensis 3.7 MYA, perhaps relatives of Lucy whose skeletal remains were found nearby in 1974 and named for the Beatles song that played over and over at the field camp on the eve of discovery (in the sky with diamonds) [6]. Man walked early. Why?

With the same energy expenditure, a human on two feet can cover at least twice as much distance in a day as can a chimpanzee using four; bipedalism’s efficiency is a matter of the forces and motions of physics [4]. This seems counterintuitive as four legged animals are much faster – but that is only in the short term; sprinters do not run marathons. It stands to reason (pun intended) that more distance for less energy is a compelling survival enhancing mutation. Over the eons of time during which A. afarensis was sequentially succeeded by Homo habilis, H. erectus and ultimately us, it was this efficiency that stoked the evolutionary engine of adaptation. This is consistent with the ideas of Richard Fortey, a senior paleontologist at the Natural History Museum of London, who writes that “upright legs evolved first and freed the arms; thus liberated, hands learned to manipulate and to maneuver precisely … and only then did brain size became important.” The upright hominids learned to make tools (habilis means handy in Latin) to dig tubers and to stab grazing animals with whom they shared the savannah, using their bipedal stamina to outlast their prey in the struggle for survival. Those with more endurance were more successful and brought home meat to nurture their scions. We most probably evolved as man-apes whose metabolism of the physical state and sensory mechanics of the mental state were gradually adapted to walk on two legs. There is a practical test to this hypothesis – on the African savannah with an aboriginal hunter.

While there are few hunter-gatherers left due to the globalization of culture, the Hadza of northern Tanzania have persevered. Several years ago, a team of anthropologists set out to measure their metabolic rate using a relatively new method with “gold standard” accuracy called doubly-labeled water. Taking advantage of advances in the use of isotopes in medicine, deuterium, or heavy hydrogen and oxygen-18 are used to make “doubly labeled” water; both atoms are traceable. The core principle is that animal energy is generated by the oxidation of hydrocarbons with water and carbon dioxide as products. To determine the caloric expenditure over a set period, a fixed volume of deuterium, oxygen-18 water is consumed and its dilution over time measured by taking sequential urine samples to calculate carbon dioxide production. The anthropologists spent a month with the Hadza taking urine samples as they went about their physically demanding daily activities that consisted primarily of animal hunting by males and plant foraging by females. Expecting huge caloric utilization necessary for the level of activity maintained, the results from the Baylor College of Medicine were tantalizing: Hadza males used about 2500 calories a day and Hadza females used 1900, the same daily caloric requirement as that of their relatively sedentary urban cousins [5].

The implications of this study are profound. How can it be that Hadza live a life of nearly continuous energy expenditure without the requisite calories logically mandated; the logic must be flawed, but in what way? To address the conundrum, follow-up studies were done using isotopic water to measure and validate the caloric expenditures of typical urban populations. The Modeling and Epidemiological Transition Study (METS) had over 300 participants whose activities were monitored using standard fitness tracking accelerometers for a week [7]. Those participants who had minimal movement, the louche couch-potato crowd, used about 200 calories less than those who subscribed to an exercise regimen of some kind – corresponding to about the same 2500 calories used daily by the Hadza. But what was more surprising was that the daily caloric expenditure of those study participants who engaged in rigorous and frequent exercise was the same as those with moderate exercise. This means that, contrary to everything we have thought about exercise and energy, there is a plateau in caloric utilization and that moderate exercise on a periodic basis is sufficient to reach it.

Two evident truths are implicit. The first is that exercise beyond a certain minimum does not burn more calories and that more exercise will not in and of itself result in weight reduction. This means that it is all about calories in, and that the 37 percent (and counting) of American adults who are obese eat too much and not exercise too little. It also means that a person who is fit should be able to travel long distances without continuous food supplements. Those who have participated in endurance events such as marathons or long-distance hikes will no doubt have noticed that they don’t need to consume thousands of extra calories before, during or after; the pre-marathon pasta supper only makes you constipated. However, it is absolutely necessary to train the body to store energy with a program of marathon training in which distance is progressively increased. But the second evident truth is more compelling – that “calories burned” are independent of energy expended, an oxymoron it would seem (and probably is). There is only speculation as to causation in the scientific community at present; like dark energy and dark latter, “missing calories” are a black hole.

The most logical explanation is that calories burned equate to the energy expended and that the “missing calories” are being diverted from one function to another and are not really missing. The business of running the body’s nervous, cardiovascular, digestive, endocrine, and supporting systems is known as the basal metabolic rate or BMR; it accounts for approximately 70 percent of total daily energy required for an adult male – about 1700 out of 2500. The brain and its nervous network use the lion’s share; about one quarter of everything you eat runs your brain. That this distinguishes us from our primate cousins has been established; humans burn about 500 calories more per day than chimpanzees or gorillas [8]. The immune system is also relatively expensive from a caloric perspective. The remaining 30 percent of available calories must then be the font from which we draw on for the kinetic energy of muscles moving torso, arms and legs, the musculoskeletal system. It is the evolved parsimony of bipedalism that makes this possible. It is also evident that additional energy can be drawn away from other bodily functions within limits to allow for some degree of overreach. For an active healthy adult and Hadza, the result is health in body and mind.

What does all this mean for hiking and health? Herman Pontzer, an anthropologist at Hunter College and one of the Hadza researchers opined that “metabolic adaptation to activity is one of the reasons exercise keeps us healthy, diverting energy away from activities such as inflammation that can have negative consequences if they go on too long.” There are two parts to this observation. The first is that regular exercise is the key to a properly functioning metabolism; that hiking is the exercise that was the survival factor in human evolution and that it is therefore the best way to keep the body in tune over time. The second part is that the energy that is not used by those who do not exercise is diverted into other activities, like inflammation. Taking this a step further, it is reasonable to attribute the spate of modern ailments to too many calories looking for something to do. The industrial revolution was powered using steam from water boiled by burning coal or wood to do work that was formerly done by man, beast, water or wind. Over the last 200 years, Homo sapiens have been conducting an uncontrolled experiment with physiology to see what happens when you promote sitting and riding over standing and walking.

Wild mice offer a window into the prelapsarian world of nature and its prerogatives. That caged laboratory mice are provided with an exercise wheel is not a matter of experimental protocol; rodents are runners; the wheel satisfies their primordial need to move. To test the ‘mice must run’ theory a group of Dutch researchers placed a wheel in an urban park with a surveillance camera. The wheel was in almost continuous use by wild mice sequentially spending up to fifteen minutes in seemingly pointless running in place in the midst of their scurrying to or from their appointed rounds. Nearly defenseless rodents evolved to run for many of the same reasons that humans evolved to walk. Mice need to run to survive and their behavior with an exercise wheel is instinctual [9]. In an ironic twist, mice are used for many of the epidemiology studies as surrogates for humans; the correlation has always been subjective to some degree due to physiological differences. It has been found that laboratory mice that are kept in cages with no exercise become obese, have compromised immune systems and become cancerous before scientists can even start their planned experiments [10].

Does the need to exercise apply to humans? Empirically yes, as has been known for some time. In the middle of the last century, a British researcher named Morris became intrigued by the startling rise in heart-attacks incident to the industrial revolution and hypothesized that they may correlate to lack of exercise. London’s iconic double-decker buses provided the ideal controlled study. Using medical records to compare the relative health of the immobile drivers with the stair climbing conductors, he found that the former had twice the heart attack rate as the latter [11]. While this result was initially met with skepticism in the scientific community, thousands of research studies have confirmed that there is an incontrovertible link between exercise and health and that many chronic diseases are involved. Hiking is the best of exercises and is necessary and sufficient to sustain health.

But we do not know why. A recent and provocative study conducted in by Dr. David James at the University of Sydney in Australia confirms the dearth of knowledge about exercise and health. Four healthy adult men agreed to have muscle biopsies taken before and after ten minutes of very rigorous exercise. An analysis of the protein structure revealed that there were over a thousand changes of which only one tenth could be explained with known physiology. This ground-breaking study offers a glimpse into the complex operation of the human metabolic machine that may ultimately yield the true nature of the cause and effect of exercise. The conclusion reached by James was that “exercise is the most powerful therapy for many human diseases, including type 2 diabetes, cardiovascular disease and neurological disorders.” [12]

Correlation is not causation. While it is demonstrably true that exercise correlates to improved health outcomes, it is premature to assert a causative quid pro quo. However, the facts are compelling. Humans evolved as the first bipedal mammal and survived through attrition of less efficient individuals. For almost all human history, the exercise of living as a hunter gatherer mandated walking, climbing, digging and carrying; the Hadza attest to the healthy result. Even after the advent of agriculture in Mesopotamia and concurrently in China about 10,000 years ago, movement by foot from farm to field and the rigors of reaping sufficed. The sedentary stasis that has become increasingly pervasive over the last one hundred years has occurred in tandem with the rise of many pernicious maladies, both physical and mental. While it is not legitimate to aver unequivocally that sloth begets sickness, it is legitimate to pronounce exercise as a demonstrative boon to health. Among other things, regular exercise has been shown to reduce the incidence of colds, protect against hearing loss, lower the risk of cataracts, improve sleep patterns, lower rates of urinary incontinence, and, yes, improve sexual potency [13]. Hiking is what human nature intended when we first set out across the savannah, and for our own best interests of health and well-being, we must retrogress to the halcyon hiking days of yore. Ambulare ergo sum.

References :

1. Thoreau, Henry David – Excerpted from Walking, sometimes referred to as “The Wild”, a lecture by Henry David Thoreau first delivered at the Concord Lyceum on April 23, 1851. First published as an essay in the Atlantic Monthly after his death in 1862. This compilation of talks provides the essence of the nature to the physical, mental, and spiritual goodwill of mankind.

2. Wade, Nicholas, Before the Dawn, Penguin Group, New York NY, 2006. A general overview of human evolution that provides a snapshot of DNA or molecular anthropology, a field that is changing rapidly with new discoveries and methods.

3. Jansen, E. et al “Paleoclimate”, In: Climate Change 2007: The Physical Science Basis. Contribution of Working Group Ito the 4th Assessment Report of the Intergovernmental Panel on Climate Change (IPCC). An excellent technical summary of a complex history.

4. Fortey, Richard, Life, A Natural History of the First 4 Billion Years of Life on Earth, Random House, New York, NY, 1997 pp 60-62. A very readable summary of the forces and factors that shaped the world we inhabit.

5. University of Arizona. (2007, July 17). “Study Identifies Energy Efficiency as Reason for Evolution of Upright Walking”. ScienceDaily. Retrieved March 1, 2018, from http://www.sciencedaily.com/releases/2007/07/070716191140.htm

6. Pontzer, Herman “Exercise Paradox” Scientific American, February 2017 pp 27-31. This study of nomadic foragers is of seminal importance to understanding the use of calories by humans and the degree to which activity is involved in their expenditure.

7. https://clinicaltrials.gov/ct2/show/NCT02925156 The Modeling and Epidemiological Transition Study is sponsored by Loyola University

8. Pontzer Op cit.

9. Twilley, Nicola, “The Exercise Pill” The New Yorker 6 November 2017 pp. 30-35. A summary of some interesting experiments about exercise, diet and weight loss.

10. Grimm, D. “The Happiness Project” Science 9 February 2018 pp 624 – 630

11. Morris, J.N., Heady, J.A., Raffle, P.A.B., Roberts, C.G., and Parks, J.W., 1953. “Coronary heart disease and physical activity of work”. Lancet 265, pp. 1053-1057

12. James, David E. et al “Global Phosphoproteomic Analysis of Human Skeletal Muscle Reveals a Network of Exercise-Regulated Kinases and AMPK Substances.” Cell Metabolism 22 pp 922-935 3 November 2015.

13. Davis Robert J. “Why Exercise? Six Surprising Health Benefits.” Washington Post 20 June 2017. This article summarizes a number of studies about the benefits of moderate exercise and health benefits from better sex to fewer colds.