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University of California Press

About the Book

Cannabis: Evolution and Ethnobotany is a comprehensive, interdisciplinary exploration of the natural origins and early evolution of this famous plant, highlighting its historic role in the development of human societies. Cannabis has long been prized for the strong and durable fiber in its stalks, its edible and oil-rich seeds, and the psychoactive and medicinal compounds produced by its female flowers. The culturally valuable and often irreplaceable goods derived from cannabis deeply influenced the commercial, medical, ritual, and religious practices of cultures throughout the ages, and human desire for these commodities directed the evolution of the plant toward its contemporary varieties. As interest in cannabis grows and public debate over its many uses rises, this book will help us understand why humanity continues to rely on this plant and adapts it to suit our needs.

About the Author

Robert C. Clarke is Cannabis researcher and Projects Manager for the International Hemp Association in Amsterdam and the author of Marijuana Botany and Hashish!
Mark D. Merlin is Botany Professor at University of Hawai’i at Manoa and author of On the Trail of the Ancient Opium Poppy.

Table of Contents

Introduction to the Multipurpose Plant Cannabis
In the beginning: Circumstances of early human contact with Cannabis
A brief summary of the long and diverse history of relationships between Cannabis and humans
What shall we call these plants?
Should we praise or condemn this multipurpose plant?
What we discuss in this book

Chapter 1: Natural Origins and Early Evolution of Cannabis
Introduction
Basic life cycle of Cannabis
Ecological requirements of Cannabis: Sunlight, temperature, water and soil
Cannabis origin and evolution studies
Central Asia: Vavilov and the origins of Cannabis
Cannabis and grapes
Theories for South Asian origin of domesticated Cannabis
Model for the early evolution of Cannabis
Summary and conclusions

Chapter 2: Ethnobotanical Origins, Early Cultivation and Evolution through Human Selection
Introduction
First contacts: Origins of Human-Cannabis relationships
Transitions to cultivation and civilization
Earliest uses of Cannabis: Useful traits for ancient people
Evolution of Cannabis through human selection
Disruptive selection
Origin from weedy populations
Natural hybridization: Introgression vs. isolation
Artificial hybridization
Atavism
Isolation of populations
Population size and changes in variability
Evolutionary effects of dioecy
Effects of human selection on sexual expression for different products - Seeds, fibers, marijuana and hashish
Sexual dimorphism and selection
Phenotypic changes during domestication - Seeds, fibers and inflorescences
Directional evolutionary changes
Cannabinoid profile
Timing of floral maturation
Evolution of cannabinoid phenotypes
Geographical distribution of cannabinoid phenotypes
North America; Western Europe; Eastern Europe; Central America and the Caribbean; South America; Middle East; East Asia; Indian Subcontinent; Southeast Asia; Equatorial Africa; South and East Africa
Summary and conclusions

Chapter 3: Cultural Diffusion of Cannabis
Introduction
Methodology: The multidisciplinary approach
Types of archaeobotanical evidence for Cannabis
Seeds, fibers, pollen, fiber and seed impressions, other carbonized remains, chemical analysis and phytoliths
Written records of Cannabis presence and use
Non-human agencies affecting the geographical range of Cannabis
Human impact on the dispersal and expanding geographical range of Cannabis
Early relationships among humans and Cannabis in Central Asia
Fishing and hemp
Hemp, humans and horses in Eurasia
Scythians and Cannabis
Archaeological and historical evidence for the spread of Cannabis
Diffusion throughout East Asia
Diffusion from northeastern China into Korea and Japan
Diffusion into South Asia
Archaeobotanical evidence from South Asia
Diffusion into Southwest Asia and Egypt
Diffusion into Europe and the Mediterranean
Romania, Bulgaria, Hungary, Poland, Baltic region, Finland, Austria, Czech Republic and Slovakia, Germany, Switzerland, Northern France, Iberian Peninsula, Netherlands, Sweden, Norway, Denmark, British Isles, and the Mediterranean
Dispersal phases within and beyond Eurasia
Phase One: Primary dispersal across Eurasia – ca. 10,000 to 2000 BP
Phase Two: Spread into Africa and Southeast Asia - ca. 2000 to 500 BP
Phase Three: Migration to the New World - 1545 to 1800
Phase Four: Migration to the New World - 1800 to 1945
Phase Five: Migration after the Second World War - 1945 to 1990
Phase Six: Artificial environments and the proliferation of industrial hemp – 1990 to the present
Summary and conclusions: Cannabis' dispersal from an evolutionary point of view

Chapter 4: History of Cannabis Use for Fiber
Introduction
Textile basics
Historical and archaeological evidence for Cannabis fiber use in China
Hemp in clothing, lacquerware, weapons and ships in ancient China
Traditional Korea
Contemporary South Korea and North Korea
Ancient Japan and hemp
Ancient evidence from South Asia, Southwest Asia and Egypt
The ancient Mediterranean region
Ancient Europe north of the Mediterranean
Hemp fiber use spreads to the New World
Some aspects of the recent history of hemp
Cannabis and paper
Advent and early history of papermaking in China
Hemp paper in ancient Korea and Japan
Dispersal to North Africa and Europe
Hemp paper production in North America
Summary and conclusions

Chapter 5: Food, feed and oil uses of hemp seed
Introduction
Human food and animal feed uses of hemp seeds
Early hemp seed use in China: Neolithic Period through the Han Dynasty
Hemp seed oil in ancient China
Ancient evidence for traditional production and use beyond China
Korea; Japan; South and Southwest Asia; Central and Eastern Europe; Mediterranean and Western European Regions
Present-day hemp seed production and use
Summary and conclusions

Chapter 6: Historical Aspects of Psychoactive Cannabis Use for Ritual and Recreation
Introduction
Discovery of the euphoriant properties of Cannabis in Eurasia.
Central Asia
China
Taoism and tales of Ma Gu
India and Nepal
Was Soma Cannabis?
South Asian psychoactive Cannabis products
Hindu acceptance of ritual bhang use
Shiva worship and Cannabis
Other occasions on which bhang was used
Worship of the bhang plant
Mongols and Cannabis
Southwest Asia, the Mediterranean, Africa and Europe
The advent of Cannabis smoking: Tobacco meets hashish
Summary and conclusions

Chapter 7: Ethnobotanical history and contemporary context of medicinal Cannabis
Introduction
Early East Asian medicinal use
South and Southeast Asian medical traditions
Egyptian medicinal use
Cannabis in early Middle Eastern and later Islamic medicine
Medicinal use in Africa and South America
European medicinal Cannabis
Present-day Western medicinal applications of Cannabis
Summary and conclusions

Chapter 8: Non-psychoactive Ritual Uses of Cannabis
Introduction
Hempen rituals of major religions – Shamanic influences survive repression
Archaeological remains from ritual contexts – Central Asia, China and Europe
The Hmong – Spirit travel in healing, life-cycle and funerary rituals
China – Shamanism, Taoism and Confucianism
Korea – Shamanic funerary rites, Confucian mourning and ancestor worship
Japan – Shamanist, Shinto and Buddhist hemp traditions
Europe and the Middle East – Judaeo-Christian hemp rituals
Hangings
Summary and conclusions

Chapter 9: Recent history of Cannabis Breeding
Introduction
European hemp breeding
North American hemp breeding
Introduction of NLD Cannabis to North America
Breeding history of NLD varieties
Introduction of BLD Cannabis
Recent trends in Cannabis breeding
Summary and conclusions

Chapter 10: Classical and molecular taxonomy of Cannabis
Introduction
One, two or three species?
History of Cannabis taxonomy
Recent advances in Cannabis taxonomy
Genetic and historical model for the evolution of Cannabis biotypes
Recent geographical distributions of Cannabis biotypes
Europe and the former Soviet Union; China; Central Asia, Afghanistan and Turkestan; India and Nepal; Southeast Asia; Africa and the Middle East; and the New World
Summary and conclusions

Chapter 11: Hypotheses Concerning the Early Evolution of Cannabis
Introduction
Prehistoric climate change and plant distribution: Pleistocene and Holocene ranges
Early human migrations
Plant speciation and colonization: Pleistocene refugia, post-glacial population expansion, and speciation rate
Early evolution of Cannabaceae: The hemp and hop family
Breeding systems and reproductive strategies as clues to geographical origin: Angiospermy, annuality, anemophily, dioecy and sex determination
Reconstruction of a Cannabaceae ancestor
Summary and conclusions

Chapter 12: Cannabis and Homo sapiens – Present position and future directions
Introduction
The long term relationship
Summary of Cannabis’ evolution
Cannabis' influence on the evolution of human culture
A case for social benefits from Cannabis’ psychoactivity Human influence on Cannabis’ evolution
Environmental impact of the Human-Cannabis relationship
Coevolution of Cannabis and humans: Fresh concepts
Present position of the Human-Cannabis relationship
Remaining questions and future directions

Reviews

"This well-written work will be useful for freshmen through seniors in higher educations. Researchers and teachers will also find it extremely helpful, and it will intrigue even casual readers."
CHOICE Magazine
"A valuable reference."
Plant Ecology and Evolution
"Sure to entertain any cannabis fan."
 
High Times
"Clarke and Merlin have crafted a volume in which each chapter can easily stand alone and will be accessible to a wide range of readers."
The AAG Review OF BOOKS
"Well-organized, accessible, and comprehensive . . . a reference that should be in the possession of experts as well as aficionados."
The Quarterly Review of Biology
"The authors boldly demonstrate their capacity to survey both the biological evolution and widely varied human cultures' uses of cannabis. In doing so, they have produced a work that is thorough, globally ambitious, and carefully constructed. The extraordinary power and range of their cross-cultural perspectives are likely to elicit fresh consideration of familiar studies." —Richard Tucker, School of Natural Resources and Environment, University of Michigan

"Cannabis is one of the best, if not the best history of the extraordinary plant Cannabis sativa that I have read. It is encyclopedic in its scope, painstakingly documented, and well written. A must for libraries, cannabis scholars and the growing number of readers who are interested in this remarkable plant." —Lester Grinspoon, Emeritus Associate Professor of Psychiatry at Harvard Medical School and author of Marihuana Reconsidered and Marihuana, the Forbidden Medicine

"This is a unique and valuable work. It aptly summarizes the voluminous literature on cannabis to bring the reader a better understanding of its origins and uses, as well as the relationship with man, its chief employer and manipulator. The authors' experience in the subject makes them uniquely qualified to synthesize and interpret the material in a coherent manner." —Ethan Russo, President of the International Cannabinoid Research Society

Awards

  • Mary W. Klinger Book Award 2014, Society for Economic Botany