ers, such as orchids, could not have arisen by chance. Darwin
viewed floral diversification as evidence for his theory of evolution by natural selection. His works have provided the conceptual underpinning for understanding that floral adaptations
are the mechanisms responsible for evolutionary transitions in
reproductive systems.
Olof Swartz, a Swedish botanist, who studied under Linnaeus
filius, was the first specialist in orchid taxonomy; he published
a morphological analysis and a classification in modern orchid
terminology (1797).
Louis Claude Richard (1817) a French botanist, gave us much
of the descriptive terminology for sexual morphology used in
orchid literature in a paper by on European orchids. Richard
emphasized the structure of the pollinia and details of the gynostemium and depicted details of the critical characters on a
Genitalia Orchidearum plate.
John Lindley, English botanist, expanded hierarchical orchid
classification by using a category between family and tribe in his
Orchidearum Sceletos (1826) that has become subfamily. Lindley
became convinced of the superiority of the “natural” classification system of Jussieu over the “artificial” system of Linnaeus
through arduous study of character patterns.
George Bentham continued Lindley’s work in collaboration
with Sir Joseph Hooker. Their great systematic work for flowering plants, Genera Plantarum (1883), became the classification
system used in the Kew Herbarium.
The German biologist Willi Hennig is considered the founder
of phylogenetic systematics (cladistics). His approach to biological classification is to group organisms based on whether or not
they have one or more shared unique characteristics that come
from the group’s last common ancestor. Members of that group
are thought to share a common history and therefore are considered to be more closely related. Hennig’s book, Phylogenetic
Systematics (1966), introduced the cladistic analysis methods
that would be critical in the coming age of molecular systematics.
Robert Dressler’s world-class treatment of the family, The orchids: Natural History and Classification (1981), was heralded
as a modern multidisciplinary treatment of Orchidaceae that
would be a significant factor for next generation of orchidologists. Dressler updated his treatment with the truly superb Phylogeny and Classification of the Orchid Family (1993). As good
as this comprehensive classification is, it relies heavily on morphology and a few characters, such as anther configuration and
pollinarium structure and therefore some of the taxa are not
monophyletic.
Deoxyribonucleic acid (DNA) may be considered the ultimate
form of sexual expression. By the late 1940s, DNA was largely
accepted as the genetic molecule. Watson and Crick showed that
each strand of the DNA molecule was a template for the other
strand (1953). Their discovery has been called the most important biological find of the last 100 years, and the prediction that
it opened the scientific frontier for the next 100 years is coming
to fruition.
The polymerase chain reaction (PCR), developed in 1983 by
Kary Mullis, was a biochemical technology needed to sequence
DNA. The indispensable technique allows a single piece of DNA
to be amplified generating thousands to millions of copies. These
copies are used for DNA sequencing, combined with computer
analysis to create a DNA-based phylogeny.
The groundwork for Genera Orchidacearum started with traditional medicine, preceded into artificial grouping, advanced to
natural classifications, included expanded character sets, added
new methods of analyses, and became