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In the midst of significant advancements in research and a burgeoning interest in the botanical field, the evolutionary pathway of Cannabis Sativa steadfastly holds its secrets, enshrouded in a veil of mystery and speculation. A myriad of questions vigorously swirl and persistently hover, casting shadows of doubt on the current scientific understanding of Cannabis Sativa, a unique phenomenon that manifests robustly in the contemporary era.
The focal point of our inquiries boldly demands a rigorous exploration into the exact delineation of the species – is Cannabis Sativa a unified giant in the botanical realm, or does it daringly fracture, splintering into several distinct species with a panache that defies simplicity? Moreover, we find ourselves at the threshold of deciphering the true connotations and implications encapsulated within the vibrant and often perplexing terminologies “Sativa” and “indicia”, terms that beckon with a tantalizing allure, promising revelations that continue to elude definitive categorization.
In this electrifying juncture of botanical exploration, we assert that it is of paramount importance to forge ahead, delving deeper with an adventurous spirit, fiercely determined to unravel the complex enigmas encapsulating Cannabis Sativa. This quest beckons us, urging us to foster a rich comprehension of its historical trajectory, a pathway that holds the potential to catalyze and augment our present explorative endeavors substantially, leading us to uncharted territories teeming with promise and exhilarating discoveries.
At this point, it’s worth noting that the scientific community generally holds a well-established view on the origins of the Cannabis genus. It is conjectured that the genesis of this genus can be pinpointed to the expansive terrains of Central Asia. Subsequent to its emergence, it embarked on a prolific journey, traversing across geographical boundaries, proliferating, and diversifying extensively to grace various corners of the globe. There exists a corroborated consensus that the interaction between humans and the cannabis plant had been firmly established towards the closure of the last glacial period, which transpired approximately 12,000 years in the annals of history.
However, as we venture further back in time to explore the antecedents of this intriguing plant species, the narrative becomes increasingly fragmented and obscured, offering only fleeting glimpses into its ancient lineage. Thus, it is incumbent upon us to scrutinize and analyze the tangible fragments of knowledge at our disposal. Let us embark on an intellectual expedition to elucidate the multifaceted and riveting evolutionary narrative of cannabis, retracing our steps to the very inception where it all began, and gradually unfurling the tapestry that encapsulates its rich and diverse heritage.
Land Plants: A History of Growth
In the annals of the earth’s vibrant biological history, it is posited that a monumental divergence occurred approximately 1.6 billion years ago, marking the genesis of distinct evolutionary paths for the plant, animal, and fungi kingdoms. During this ancient epoch, the entities representing these kingdoms were fundamentally rudimentary, predominantly aquatic organisms such as algae and amoebae, embarking upon their respective evolutionary journeys within the nurturing aquatic environments that hosted them.
Around the notable mark of 500 million years ago, a significant evolutionary milestone was attained when land plants heralded their inception, emerging from ancestral mats of algae that had adeptly adapted to colonize rocky terrains. Initially, these pioneers of terrestrial vegetation were characterized by a simplistic structural composition, resembling mosses devoid of complex features such as authentic roots, leaves, or seeds, which are indicative of more advanced botanical species. As time unfolded, these primordial plants underwent decomposition, playing an instrumental role in nurturing and fostering the development of soil, which subsequently became hospitable to the propagation of more intricate and complex organisms. This evolutionary procession reached a crescendo around 350 million years ago, where the landmasses witnessed a proliferation of lush forests dominated by ferns and gymnosperms, such as conifers, that cloaked vast stretches of earth in vibrant green foliage.
In the grand narrative of terrestrial plant evolution, flowering plants, or angiosperms, emerged as the most recent entrants in the biological theatre. This group, to which cannabis belongs, made its grand debut approximately 130 million years ago, gracing the Cretaceous period with its presence. During this time, the earth bore witness to a fascinating juxtaposition of burgeoning flora coexisting with magnificent creatures like the Tyrannosaurus rex and Triceratops, while the reigns of Stegosaurus and Diplodocus had already faded into the annals of prehistory.
Following their emergence, the angiosperms embarked on a journey of extensive diversification, giving rise to nearly 350,000 distinct species, thereby establishing their group as the most diverse and populous faction in the botanical kingdom. This remarkable diversification has positioned angiosperms as the cornerstone of modern agriculture, with their members constituting the vast majority of crops cultivated for a myriad of purposes in contemporary agricultural practices. Their dominance underscores the intricate and dynamic evolution that has unfolded over millions of years, painting a vivid tapestry of the earth’s biological narrative.
When did the Cannabaceae family start evolving?
It is hypothesized that the Cannabaceae family, renowned primarily due to its most notable member, cannabis, underwent evolutionary processes around 60 million years ago (Ma), a timeframe deduced through meticulous genetic analyses and comparative studies with phylogenetically akin plant groups, such as Moraceae, the family to which mulberries belong. The comprehensive research encapsulated in the seminal work “Cannabis: Evolution and Ethnobotany” authored by Clarke and Merlin in the year 2013, delineates that the genus Cannabis manifested a bifurcation initially, followed by a subsequent divergence of the Humulus genus, synonymous with the hop family, from the Cannabaceae lineage approximately 22 million years ago. In addition, investigations spearheaded by GW Pharmaceuticals propose a time scale wherein Cannabis experienced a distinctive evolutionary split from Humulus around 28 million years ago, further contributing to our nuanced understanding of the phylogenetic trajectory of this botanical family.
Fossilized leaf remnants bearing a striking resemblance to contemporary cannabis and estimated to be approximately 38 million years old have allegedly been discovered in central Kazakhstan. This revelation could potentially indicate that the period of divergence transpired significantly earlier in the geological timeline than previously surmised. Without question, forthcoming genetic research endeavors are anticipated to elucidate this matter with greater precision and depth.
Turning our attention to the precursors of the modern cannabis plant, one might inquire about their appearance and biological attributes. While the available empirical data remains relatively scant, an analytical approach would be to scrutinize the traits prevalent among its nearest extant kin, thereby facilitating a reasoned hypothesis concerning its ancestral characteristics.
5 Common Traits Shared by Cannabis and Hops
Among the plethora of species inhabiting Earth presently, cannabis bears the closest resemblance to hops, both falling under the Cannabaceae family. Despite cannabis being the solitary species encompassed within its respective genus, also named Cannabis, it shares noteworthy traits with the three species classified under the Humulus genus, which embodies hops:
- A prominent characteristic manifesting in both genres is the secretion of resin, laden with an abundant concentration of terpenes like myrcene and humulene. These terpenes predominantly pervade the hop species, while also constituting a significant proportion of various cannabis strains.
- Moreover, a striking similarity can be observed in the morphological structure of their leaves. Both species exhibit palmate leaf arrangements, a trait mirrored across numerous members of the Cannabaceae family. This entails that the leaves resemble an open hand with finger-like projections, where each individual leaflet portrays serrated margins.
- Furthermore, both botanical groups adhere to a dioecious reproduction approach, which entails the segregation of male and female entities onto distinct plants. This mode of reproduction is somewhat scarce in the flowering plant domain, manifesting in merely about 7% of all species. In tandem with this characteristic, both species occasionally demonstrate monoecious propensities, facilitating the existence of both male and female blossoms on a singular plant entity. This is contrary to the typical structure of angiosperms which predominantly feature unisexual blooms, amalgamating both male and female components within the same flower structure.
- In the reproductive sphere, both genres generate achenes as their respective fruits. Characterized as dry seeds enveloped within a rigid outer shell, achenes bear similarity to sunflower seeds. This is distinct from the common fruit type among the Cannabaceae species which is drupes, typified by succulent flesh encasing a rigid kernel, akin to cherries.
- Lastly, the floral structure presents another shared attribute, unveiling loose aggregations of minuscule, pale-hued blossoms on male plants, which present a marked resemblance to each other. The pollen derived from males across both species is strikingly similar, rendering it a challenging task to differentiate between them when scrutinizing ancient pollen samples. Both species also depend on wind-mediated pollination. Nonetheless, a closer inspection of female flowers, despite surface similarities, reveals a spectrum of differences that delineate the two species.
4 Disparities Between Cannabis and Hops
- In the case of hops, the female flowers congregate in clusters, forming cone-shaped structures reminiscent of pine tree cones. These hop cones are suspended individually from single stalks. Conversely, female cannabis flowers, while also clustered, grow along the plant’s stems rather than hanging from a central point.
- Female hop flowers are distinguished by their notably larger bracts, which are the small leaves accompanying the flowers. This stands in contrast to cannabis plants, although it’s worth noting that certain cannabis phenotypes may exhibit large bracts akin to those found in hops.
- Cannabis operates as an annual plant, completing its life cycle within a single year. In contrast, the hop vine’s flowering and seeding occur annually, yet it maintains a perennial rootstock from which it regenerates continuously. This enduring rootstock characteristic of hops facilitates straightforward vegetative propagation through the simple process of removing a segment of the rootstock and transplanting it. However, this method is less suited to cannabis, as it has historically been predominantly propagated through seeds. Cloning, a more recent development within the cannabis industry from a historical perspective, has gained popularity.
- When considering leaf structure, cannabis leaves are accurately classified as palmately compound. In this configuration, the leaves comprise individual, well-defined leaflets that are distinct from one another, unlike the fused lobes observed in hop leaves. Nevertheless, it is noteworthy that certain cannabis strains may occasionally exhibit palmately-lobed characteristics reminiscent of ancestral traits, as exemplified by strains like “Ducksfoot,” along with specific Afghani and Hawaiian varieties.
What were the physical characteristics of the predecessor of cannabis and hops?
Hence, it is plausible to posit that the common precursor of contemporary hops and cannabis was a botanical specimen characterized by a notable proclivity for terpene synthesis, possessed palmately-lobed leaves with serrated margins, engaged in dioecious reproduction with inclinations towards monoecious tendencies, featured achenes as part of its reproductive apparatus, exhibited distinct clusters of male and female blossoms, and bore female flowers adorned with substantial bracts.
The origins of both cannabis and hops are speculated to be traced back to the Asian continent, with hops believed to have originated in the realms of China and cannabis potentially evolving within the expansive Central Asian territory encompassing segments of western China. Consequently, it is reasonable to infer that the common progenitor also thrived in these geographical domains, a notion congruent with the preponderance of Cannabaceae flora in the Asian milieu.
Although the precise growth habit of this ancestral plant remains elusive – whether it was akin to the shrub-like stature of cannabis or the twining disposition of hops – the absence of climbing attributes in other Cannabaceae species strongly implies that the evolution of hops into bines, resembling twining plants akin to vines, transpired subsequent to the divergence of the two lineages. While sporadic accounts suggest cannabis may occasionally exhibit vine-like traits, such reports remain anecdotal, making it more probable that the common ancestor adhered to an upright growth pattern akin to that of cannabis.
What occurred after the cannabis family branched apart?
If we consider that the divergence between the Cannabis and Humulus genera took place approximately 28 million years ago, it becomes apparent that the cannabis plant had nearly that entire duration to undergo evolutionary changes prior to the emergence of the Homo genus, which occurred around 2.8 million years ago. Additionally, there was an extended period of approximately one million years or even longer before the initial appearance of the Homo species, specifically H. erectus, in the Asian continent. Over the course of this protracted timeframe, substantial changes in climate and atmospheric conditions transpired, imposing significant challenges on plant ecosystems and compelling them to undergo swift adaptations to ensure their survival.
For a substantial portion of its evolutionary timeline, which spans over 25 million years, cannabis thrived in a climate characterized by a “greenhouse Earth” scenario. During this epoch, temperatures and carbon dioxide levels remained elevated, and there was an absence of glacial coverage across the globe. Within this climatic context, the cannabis plant proliferated across vast expanses of the plains and hills in Central Asia, potentially extending its reach into Southeast Asia and even parts of Europe.
Nonetheless, the global climate gradually underwent a cooling trend throughout this period, in line with recurring climatic cycles in Earth’s history. Approximately 2.6 million years ago, the planet transitioned into a new ice age that persists to the present day, with the current epoch representing an interglacial period characterized by relatively brief intervals of warmth amid lengthier, colder phases.
During this transition, extensive portions of the planet became encased in ice, featuring continental glaciers that extended as far as 40 degrees latitude from the polar regions. Consequently, a multitude of plant and animal species faced extinction or sought refuge in localized habitats that offered conditions conducive to their survival.
In what manner did cannabis sativa endure the challenges posed by the Ice Age?
The Cannabis genus fortuitously persisted through this challenging epoch by taking refuge in diverse locations within Central and Southern Asia. Among the scientific community, there exists little uncertainty that this period witnessed some of the most profound evolutionary transformations within the genus, driven by the urgent need to generate genotypes capable of thriving in markedly altered habitats. It is postulated that the adaptations leading to the emergence of the “sativa,” “indica,” and “ruderalis” biotypes likely transpired during this interval.
Furthermore, it is theorized that the cannabis plant acquired the capacity to synthesize THC (tetrahydrocannabinol) during this timeframe, owing to a mutation in the cannabinoid synthase gene. Consequently, by the time cannabis began to diversify into the distinct types recognizable today, it had already acquired the capability to produce THC. The subsequent evolutionary pressures, stemming from both human activities and environmental factors, have subsequently influenced the extent to which different populations produce THC.
The Development of “Sativa,” “Indica,” and “Ruderalis” Varieties
It is reasonable to posit that cannabis managed to maintain segments of its geographical range within Central Asia as the onset of the ice age approached. Genetic analysis has substantiated the persistence of the most diverse wild gene pool in regions encompassing Kazakhstan, Afghanistan, and western China.
Nonetheless, specific isolated populations within this genus underwent the development of distinct traits that differentiate them from the principal gene pool. Consequently, contemporary scientists confront the task of discerning whether these disparities suffice to classify them as distinct species.
Within the realm of cannabis taxonomy, two prevailing perspectives prevail. One school of thought, as expounded by Clarke and Merlin in their work “Cannabis: Evolution & Ethnobotany,” contends that the Cannabis genus comprises three species along with various subspecies. Conversely, an alternative viewpoint posits that Cannabis constitutes a solitary species, capable of manifesting a wide spectrum of traits contingent upon its environmental context. This diverse array of regional characteristics gives rise to the categorizations of “sativa,” “indica,” and “ruderalis,” albeit not conforming entirely to conventional wisdom.
In the valleys and foothills of northern India and Pakistan, an informal categorization known as “indica” came into existence. This specific category demonstrates clear seasonality, having evolved to thrive in a climate distinguished by lengthy, sun-drenched summer days and unforgiving, freezing winters. Furthermore, it is plausible that the “indica” type represents the primary “drug” biotype, and the high-THC strains commonly referred to as “sativas” may, in reality, originate from narrow-leaved subtypes within the “indica” category.
Simultaneously, cannabis dispersed and established separate populations farther south and west, inhabiting the arid steppes of Afghanistan and Turkestan. During this migration, the cannabis plant underwent a transformation, manifesting an increased size, looser flower structures, and enhanced resistance to mold. These adaptations were responsive to elevated temperatures and humidity levels. It is worth considering that the type commonly denoted as “indica” may be more accurately identified as Cannabis afghanica.
In Central and Northern Asia, the C. ruderalis variant, characterized by its diminutive stature, reduced resin production, and the capacity to flower in accordance with age, took root as a response to cold temperatures and diminished light conditions.
In various regions of Asia and parts of Europe, cannabis varieties evolved that closely resemble what is recognized as hemp today. These strains also adapted to cooler temperatures, albeit not to the same degree as ruderalis. They exhibit seasonal flowering patterns but do not produce substantial quantities of cannabinoids. Notably, European hemp belongs to the C. sativa category, whereas certain hemp populations in Asia trace their origins to C. indica.
The Cannabis genus exhibits an impressive degree of phenotypic plasticity, denoting its remarkable capacity to generate a wide array of variations in phenotype. Within this taxonomic group, fundamental distinctions between biotypes undoubtedly exist. Moreover, during the past approximately two million years, characterized by rapid evolutionary changes, these biotypes may have benefited from human intervention, possibly extending back to earlier Homo species such as H. erectus.
It is worth emphasizing that human-driven selective breeding over the course of the last 12,000 years or so has likely exerted a predominant influence as the primary selection pressure on the evolution of cannabis varieties, particularly since the conclusion of the last glacial period. In essence, our deliberate intervention has undeniably played a pivotal role in shaping the diversity and global distribution of cannabis observed today.
