Rapid Evolution of Orchids?

I thought you should see this article recently published in the CSA Journal and the Orchid Review. It ties in to your article on rapid evolution of orchids as well as your petal puppy picture.
EARLY EVOLUTION OF DOMESTICATED ORCHIDS
James Ph. Kotsybar
Roughly 14,000 years ago, a single species, the gray wolf, adopted (or was adopted by) man. Soon after, a new species emerged from the gray wolf population – our domestic canine. Once mankind began breeding dogs for certain characteristics, diversification accelerated. By the time of the Roman Empire there were six distinct types of dogs, bred for various purposes. Today, the American Kennel Club recognizes hundreds of breeds, from Chihuahua to Mastiff, all arising from a single gene pool.
What if, instead of starting with a single species, we began this process with thousands of different species (plus variants and mutations) with the potential to hybridize among themselves and related genera as well? What if this process mostly produced fertile descendants and allowed the mixing of genetic pools for countless generations? So it is with orchids. Sander’s List of Orchid Hybrids — a now ten-volume encyclopedia –– reveals the degree of diversity possible in just 200 years of selective breeding.
ORCHID ORIGINS AND ADAPTATIONS
Some botanists say the degree to which orchid genera readily hybridize with one another indicates orchids are very recently evolved. They declare orchids must be very young in evolutionary terms as evidenced by the genetic compatibility of so many genera. Others insist the ubiquitous presence of orchids worldwide is best explained if orchid ancestors came from Pangaea – the ancient, single continent from which today’s landmasses split, 225 million years ago. Mysteriously, the fossil record can validate neither theory. There simply are no confirmed fossilized orchids – not even seed or pollen microfossils. The prevailing theory that orchids split off from the modern lilies which some resemble has been staggered by recent DNA analyses which designate asparagus as orchids’ closest cousin.
While the origins of orchids are still being debated today, we have learned quite a bit about how they behave in the wild. We know they are proficient at adaptation. We know many orchids have evolved into epiphytes climbing to the treetops to find light and escape rot. In acclimating to life without soil, they have devised mechanisms to collect and store water and even resist its evaporation.
We also know orchids depend upon pollinators in order to reproduce, and their primary pollinators are flying insects. Our scrutiny reveals they have adopted various means to lure their winged liaisons, either with visual cues or with fragrances. In one of the most amazing examples, the orchid species Chiloglottis trapeziformis physically mimics and exaggerates the measurements of an attractive female wasp, and uses the same perfume! The wasp-mimicking structures on the orchids are a third longer than the actual females and over five times wider, which, proportionally, is the strongest preference of the male wasps. The orchid also produces ten times the concentration of sexual pheromones (chemical attractants). Once the orchid is pollinated (by pseudocopulation), this fragrance fades, and a new fragrance is immediately produced — that of a brooding female wasp. This new scent discourages further interaction with male wasps and sends them off to the next artificial virgins, promoting cross-pollination.
Other orchid genera have evolved equally elaborate contraptions for insect pollination. Angraecums keep nectar at the bottom of deep tubes, tailored to a moth’s proboscis. Catasetums have spring-loaded catapults that slap the pollinarium (reproductive package) onto visiting bees, sometimes with enough force to knock them off to the next flower. Cymbidiums tempt bees with pleasingly marked labella deep into the bright yellow throats of the flower where raised keels and side lobes hold them perfectly in place for precise placement of the pollinarium as they back out. Paphiopedilums and Coryanthes entice flies or bees that subsequently fall into their pouches or buckets and force them to exit along specific pathways where pollen is eventually attached to them. Brassias display markings (particularly visible in the ultraviolet spectrum in which insects see) that mimic a spider web with a spider in the center. Parasitic wasps (which paralyze spiders in order to lay their eggs inside them) come in for the attack, and this action often results in pollination. Oncidium sprays, too, it has been said, can incite a colony of bees to attack what they presume is a rival colony, enabling pollination by pseudo aggression.
Despite these seemingly clever tactics, studies have shown successful orchid seedpod production occurs rarely in nature. A fifteen-year study of a thousand plants produced only twenty-three pods. However, orchids compensate for this scarcity by the copious amount of seeds per pod and a long, productive adult life.
We also know orchid seeds survive for only a short time unless they connect with mycorrhizal fungi, which provide them needed nourishment until they are able to photosynthesize their own food. To achieve this, orchids have reduced their seed size allowing them to be carried like dust in the wind and scattered prolifically, increasing their chances of landing in a fungal crib.
ORCHIDS IN CULTIVATION
Today, due to human intervention, orchids are experiencing an explosion of gene-mixing diversity, fueling their evolution. While famous for their sub-species and varieties, the rare incidence of pollination in their former environment limited population numbers of these variants. In cultivation, plants can be made to produce pods yearly. Even more rare in Nature are hybrids. For Nature to produce a hybrid, two or more species must be blooming near each other at the same time; must be appealing to the same insect pollinator; and must have roughly the same genital proportions. Mankind, however, has eliminated geographical barriers, and progeny may come from parents of completely different cultural requirements, tempering the environmental demands of their offspring. Seasonal barriers are also eliminated because we save and store pollen, producing progeny that can bloom at any time throughout the year. Genital proportions no longer matter, since our toothpicks can carry pollinia accurately to the stigmatic surface on columns of any length, allowing for the combination of very different orchid dimensions.
Mutations have also been artificially accelerated. We create more mutant orchids than are present in the wild, both deliberately and accidentally. Laboratory orchid cultivation routinely uses chemicals to double chromosome numbers. In tissue cloning, which attempts to make exact genetic replicas, somatic deviants appear often enough for us to have coined the term “meristem mutation.” The more desirable of these genetic deviations are often cloned and circulated worldwide for more extensive use. If the new anomalous traits are heritable, new lines of breeding are fostered, as with splash petaled Cattleyas.
Criteria vary with individual hybridizers but the primary decisive factors are hardiness, length and frequency of blooming season, floriferousness and size of flowers, color and marking preferences, pleasing flower presentation and fragrances.
Environmental pressures spur evolution. Normally this is a relatively slow process (like climactic changes or mountain ranges forming), but what if these pressures were to become extreme? What if an entire population was suddenly collected from its natural environment and permanently placed into a new, artificial setting? We can see this happening with orchids, many of which no longer have a native habitat to which they may return and may only continue their existence in cultivation. Orchids are forced to adapt to or die from artificial fertilizers, human watering schedules, and all of the other house and greenhouse conditions to which they are subjected. This includes the poisons necessary to defend them against their former pollinators whom they naturally and by design attract. Within our artificial environments, cultivated selection is supplanting the random process of natural selection; the orchid breeder has extensive data on what to expect from most crosses, and, a majority of breeding choices are based on experience or a willful assessment of the likely outcome.
As the newest pollinators of orchids, we bring with us far more sophisticated options than insect matchmakers. In just the first dozen or so generations for which we are responsible it seems the potential for orchid variability is inexhaustible. We circumvent natural selection through in-vitro germination, multiplying yields by a factor of thousands over Nature’s fungal symbiosis. Careful watering, temperature regulation, providing air circulation and monitoring and eliminating their pests also boost orchid productivity. Hybrid orchids no longer come across the old environmental pressures nor the pollinators of their ancestors. In some cases, we have bred them beyond recognition by some of their former natural cohorts. Human hybridizers are now solely responsible for the evolutionary survival of many orchid strains.
THE FORMATION OF NEW SPECIES
Evolution is the process whereby populations change over time, but how do new species develop? Darwin suggested isolation. A population cut off from others (geographically or reproductively) is allowed to develop stability over many generations. Thus, our new criterion for defining species is that the descendents develop a steady population that breeds without excessive variation from one generation to the next. The fastest way to achieve this stabilization is by the repeated crossing of siblings – a type of inbreeding. Orchids are incredibly tolerant of repeated sibling crossing, allowing stabilized populations to develop without the deleterious effects of inbreeding that occur in the animal kingdom.
Free of natural impediments, our artificial hybrids are allowed to develop more quickly into species. New “species” may potentially emerge in isolated greenhouses worldwide, faster than this is believed to have occurred in the Galapagos, Australia or anywhere else on Earth. As certain hybrids stabilize their offspring population, we will be forced to consider them as species by our own definition. Undoubtedly, future botanists will endlessly debate about which “ancient” hybrids deserve to be recognized as new species. Purists may insist that for a species to exist, it needs a natural habitat, but we have not insisted upon this with dogs. Few taxonomists maintain that a Boston terrier is really just a variant of the Eurasian wolf because Massachusetts lacks a wild terrier population. It is in fact their close association with man that has become a quality that differentiates dog from wolf. Despite destruction of wild orchid habitat, the number of these domesticated orchid species in the world could increase to a million or more over the next millennium. With our help, and as long as they retain their association with man, orchids could well become the botanical life form best suited to survival in our domain.
WHO’S IN CHARGE?
Orchids are so complex and accomplished at adaptation it is easy to indulge in the common fallacy that they actually “choose” or “tempt” pollinators. Looking strictly objectively, their role in evolution is passive. However, it might still be wise to take a second look at our relationship with orchids. While it seems we have taken control of their destiny, we have seen their adaptive skills have allowed them to tap into the hungers and intimacies of insects and ultimately completely manipulate their pollinators. It’s true insects are tricked and used to transfer pollen, but orchids do not generally require bees to bring them food and water, build special structures to house them, propagate their seedlings or groom and regularly repot them. We convince ourselves orchid care is our idea. We build greenhouses and orchid labs and fuss over the plants because we have come to love their beauty of our own accord. We might be well advised to consider, however, why it is Oncidium Sharry Baby smells like chocolate. For some people, chocolate is practically a sexual pheromone, and this is not the only orchid aroma that resembles some favorite human food. There are orchids that smell like cinnamon, citrus, coconut, licorice and (of course) Vanilla. In fact, orchids produce more chemical fragrances than any other plant group — a hundred times that of roses. Many of these volatile chemicals cannot be consciously perceived and may indeed act like pheromones, giving us unconscious chemical cues whenever they are sniffed. Conceivably, this is why the custom of giving an orchid corsage began. However managed, orchids have been extremely successful at becoming established in continued cultivation, assuring their survival.
WILD SPECULATION?
Not only are orchids adaptively suited to life on Earth, but their epiphytic nature also makes them ideal candidates for space travel. Since they’ve evolved to be independent of soil and gravity, can be grown hydroponically under lights and even help purify the air, why not bring our orchids with us to our space stations and other worlds? Perhaps we will ultimately establish them extraterrestrially in a new natural habitat. It could even be argued this has happened before. Might not the reason for the absence of fossilized orchids be that they were recently brought here by beings from another world? Some of them do indeed seem quite alien.
Tomorrow’s orchids may be very different from those we know today. They may be bred to be immune to viruses and poisonous to pests. Individual blooms may be half a meter across with hundreds of flowers on a stem, blooming for most of the year. They might have twice the number of petals with ever more bizarre color combinations and patterns. We may sample “the Apple Pie Orchid” or “the Chicken Soup Orchid” in addition to “the Chocolate Orchid.” Some popularly produced Hybrid-species may look more than ever like the spiders, swans, octopus, antelope, feminine footwear or dancing ladies they are said to presently portray. As we breed, show and pedigree our botanical pets, some may even “learn” to resemble puppies.
James Ph. Kotsybar is an accredited judge of the American Orchid Society and Vice-Chairman of the Pacific South Region. He is co-owner of Chaotic Exotics (orchid nursery). He is an internationally published writer, teaches orchid horticulture at Allan Hancock College and is the founding Board Member and Advisor of California’s Coastal Valley Orchid Society.

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One thought on “Rapid Evolution of Orchids?”

James Ph. Kotsybar says:

August 14, 2006 at 11:40 PM

I thought you should see this article recently published in the CSA Journal and the Orchid Review. It ties in to your article on rapid evolution of orchids as well as your petal puppy picture.
EARLY EVOLUTION OF DOMESTICATED ORCHIDS
James Ph. Kotsybar
Roughly 14,000 years ago, a single species, the gray wolf, adopted (or was adopted by) man. Soon after, a new species emerged from the gray wolf population – our domestic canine. Once mankind began breeding dogs for certain characteristics, diversification accelerated. By the time of the Roman Empire there were six distinct types of dogs, bred for various purposes. Today, the American Kennel Club recognizes hundreds of breeds, from Chihuahua to Mastiff, all arising from a single gene pool.
What if, instead of starting with a single species, we began this process with thousands of different species (plus variants and mutations) with the potential to hybridize among themselves and related genera as well? What if this process mostly produced fertile descendants and allowed the mixing of genetic pools for countless generations? So it is with orchids. Sander’s List of Orchid Hybrids — a now ten-volume encyclopedia –– reveals the degree of diversity possible in just 200 years of selective breeding.
ORCHID ORIGINS AND ADAPTATIONS
Some botanists say the degree to which orchid genera readily hybridize with one another indicates orchids are very recently evolved. They declare orchids must be very young in evolutionary terms as evidenced by the genetic compatibility of so many genera. Others insist the ubiquitous presence of orchids worldwide is best explained if orchid ancestors came from Pangaea – the ancient, single continent from which today’s landmasses split, 225 million years ago. Mysteriously, the fossil record can validate neither theory. There simply are no confirmed fossilized orchids – not even seed or pollen microfossils. The prevailing theory that orchids split off from the modern lilies which some resemble has been staggered by recent DNA analyses which designate asparagus as orchids’ closest cousin.
While the origins of orchids are still being debated today, we have learned quite a bit about how they behave in the wild. We know they are proficient at adaptation. We know many orchids have evolved into epiphytes climbing to the treetops to find light and escape rot. In acclimating to life without soil, they have devised mechanisms to collect and store water and even resist its evaporation.
We also know orchids depend upon pollinators in order to reproduce, and their primary pollinators are flying insects. Our scrutiny reveals they have adopted various means to lure their winged liaisons, either with visual cues or with fragrances. In one of the most amazing examples, the orchid species Chiloglottis trapeziformis physically mimics and exaggerates the measurements of an attractive female wasp, and uses the same perfume! The wasp-mimicking structures on the orchids are a third longer than the actual females and over five times wider, which, proportionally, is the strongest preference of the male wasps. The orchid also produces ten times the concentration of sexual pheromones (chemical attractants). Once the orchid is pollinated (by pseudocopulation), this fragrance fades, and a new fragrance is immediately produced — that of a brooding female wasp. This new scent discourages further interaction with male wasps and sends them off to the next artificial virgins, promoting cross-pollination.
Other orchid genera have evolved equally elaborate contraptions for insect pollination. Angraecums keep nectar at the bottom of deep tubes, tailored to a moth’s proboscis. Catasetums have spring-loaded catapults that slap the pollinarium (reproductive package) onto visiting bees, sometimes with enough force to knock them off to the next flower. Cymbidiums tempt bees with pleasingly marked labella deep into the bright yellow throats of the flower where raised keels and side lobes hold them perfectly in place for precise placement of the pollinarium as they back out. Paphiopedilums and Coryanthes entice flies or bees that subsequently fall into their pouches or buckets and force them to exit along specific pathways where pollen is eventually attached to them. Brassias display markings (particularly visible in the ultraviolet spectrum in which insects see) that mimic a spider web with a spider in the center. Parasitic wasps (which paralyze spiders in order to lay their eggs inside them) come in for the attack, and this action often results in pollination. Oncidium sprays, too, it has been said, can incite a colony of bees to attack what they presume is a rival colony, enabling pollination by pseudo aggression.
Despite these seemingly clever tactics, studies have shown successful orchid seedpod production occurs rarely in nature. A fifteen-year study of a thousand plants produced only twenty-three pods. However, orchids compensate for this scarcity by the copious amount of seeds per pod and a long, productive adult life.
We also know orchid seeds survive for only a short time unless they connect with mycorrhizal fungi, which provide them needed nourishment until they are able to photosynthesize their own food. To achieve this, orchids have reduced their seed size allowing them to be carried like dust in the wind and scattered prolifically, increasing their chances of landing in a fungal crib.
ORCHIDS IN CULTIVATION
Today, due to human intervention, orchids are experiencing an explosion of gene-mixing diversity, fueling their evolution. While famous for their sub-species and varieties, the rare incidence of pollination in their former environment limited population numbers of these variants. In cultivation, plants can be made to produce pods yearly. Even more rare in Nature are hybrids. For Nature to produce a hybrid, two or more species must be blooming near each other at the same time; must be appealing to the same insect pollinator; and must have roughly the same genital proportions. Mankind, however, has eliminated geographical barriers, and progeny may come from parents of completely different cultural requirements, tempering the environmental demands of their offspring. Seasonal barriers are also eliminated because we save and store pollen, producing progeny that can bloom at any time throughout the year. Genital proportions no longer matter, since our toothpicks can carry pollinia accurately to the stigmatic surface on columns of any length, allowing for the combination of very different orchid dimensions.
Mutations have also been artificially accelerated. We create more mutant orchids than are present in the wild, both deliberately and accidentally. Laboratory orchid cultivation routinely uses chemicals to double chromosome numbers. In tissue cloning, which attempts to make exact genetic replicas, somatic deviants appear often enough for us to have coined the term “meristem mutation.” The more desirable of these genetic deviations are often cloned and circulated worldwide for more extensive use. If the new anomalous traits are heritable, new lines of breeding are fostered, as with splash petaled Cattleyas.
Criteria vary with individual hybridizers but the primary decisive factors are hardiness, length and frequency of blooming season, floriferousness and size of flowers, color and marking preferences, pleasing flower presentation and fragrances.
Environmental pressures spur evolution. Normally this is a relatively slow process (like climactic changes or mountain ranges forming), but what if these pressures were to become extreme? What if an entire population was suddenly collected from its natural environment and permanently placed into a new, artificial setting? We can see this happening with orchids, many of which no longer have a native habitat to which they may return and may only continue their existence in cultivation. Orchids are forced to adapt to or die from artificial fertilizers, human watering schedules, and all of the other house and greenhouse conditions to which they are subjected. This includes the poisons necessary to defend them against their former pollinators whom they naturally and by design attract. Within our artificial environments, cultivated selection is supplanting the random process of natural selection; the orchid breeder has extensive data on what to expect from most crosses, and, a majority of breeding choices are based on experience or a willful assessment of the likely outcome.
As the newest pollinators of orchids, we bring with us far more sophisticated options than insect matchmakers. In just the first dozen or so generations for which we are responsible it seems the potential for orchid variability is inexhaustible. We circumvent natural selection through in-vitro germination, multiplying yields by a factor of thousands over Nature’s fungal symbiosis. Careful watering, temperature regulation, providing air circulation and monitoring and eliminating their pests also boost orchid productivity. Hybrid orchids no longer come across the old environmental pressures nor the pollinators of their ancestors. In some cases, we have bred them beyond recognition by some of their former natural cohorts. Human hybridizers are now solely responsible for the evolutionary survival of many orchid strains.
THE FORMATION OF NEW SPECIES
Evolution is the process whereby populations change over time, but how do new species develop? Darwin suggested isolation. A population cut off from others (geographically or reproductively) is allowed to develop stability over many generations. Thus, our new criterion for defining species is that the descendents develop a steady population that breeds without excessive variation from one generation to the next. The fastest way to achieve this stabilization is by the repeated crossing of siblings – a type of inbreeding. Orchids are incredibly tolerant of repeated sibling crossing, allowing stabilized populations to develop without the deleterious effects of inbreeding that occur in the animal kingdom.
Free of natural impediments, our artificial hybrids are allowed to develop more quickly into species. New “species” may potentially emerge in isolated greenhouses worldwide, faster than this is believed to have occurred in the Galapagos, Australia or anywhere else on Earth. As certain hybrids stabilize their offspring population, we will be forced to consider them as species by our own definition. Undoubtedly, future botanists will endlessly debate about which “ancient” hybrids deserve to be recognized as new species. Purists may insist that for a species to exist, it needs a natural habitat, but we have not insisted upon this with dogs. Few taxonomists maintain that a Boston terrier is really just a variant of the Eurasian wolf because Massachusetts lacks a wild terrier population. It is in fact their close association with man that has become a quality that differentiates dog from wolf. Despite destruction of wild orchid habitat, the number of these domesticated orchid species in the world could increase to a million or more over the next millennium. With our help, and as long as they retain their association with man, orchids could well become the botanical life form best suited to survival in our domain.
WHO’S IN CHARGE?
Orchids are so complex and accomplished at adaptation it is easy to indulge in the common fallacy that they actually “choose” or “tempt” pollinators. Looking strictly objectively, their role in evolution is passive. However, it might still be wise to take a second look at our relationship with orchids. While it seems we have taken control of their destiny, we have seen their adaptive skills have allowed them to tap into the hungers and intimacies of insects and ultimately completely manipulate their pollinators. It’s true insects are tricked and used to transfer pollen, but orchids do not generally require bees to bring them food and water, build special structures to house them, propagate their seedlings or groom and regularly repot them. We convince ourselves orchid care is our idea. We build greenhouses and orchid labs and fuss over the plants because we have come to love their beauty of our own accord. We might be well advised to consider, however, why it is Oncidium Sharry Baby smells like chocolate. For some people, chocolate is practically a sexual pheromone, and this is not the only orchid aroma that resembles some favorite human food. There are orchids that smell like cinnamon, citrus, coconut, licorice and (of course) Vanilla. In fact, orchids produce more chemical fragrances than any other plant group — a hundred times that of roses. Many of these volatile chemicals cannot be consciously perceived and may indeed act like pheromones, giving us unconscious chemical cues whenever they are sniffed. Conceivably, this is why the custom of giving an orchid corsage began. However managed, orchids have been extremely successful at becoming established in continued cultivation, assuring their survival.
WILD SPECULATION?
Not only are orchids adaptively suited to life on Earth, but their epiphytic nature also makes them ideal candidates for space travel. Since they’ve evolved to be independent of soil and gravity, can be grown hydroponically under lights and even help purify the air, why not bring our orchids with us to our space stations and other worlds? Perhaps we will ultimately establish them extraterrestrially in a new natural habitat. It could even be argued this has happened before. Might not the reason for the absence of fossilized orchids be that they were recently brought here by beings from another world? Some of them do indeed seem quite alien.
Tomorrow’s orchids may be very different from those we know today. They may be bred to be immune to viruses and poisonous to pests. Individual blooms may be half a meter across with hundreds of flowers on a stem, blooming for most of the year. They might have twice the number of petals with ever more bizarre color combinations and patterns. We may sample “the Apple Pie Orchid” or “the Chicken Soup Orchid” in addition to “the Chocolate Orchid.” Some popularly produced Hybrid-species may look more than ever like the spiders, swans, octopus, antelope, feminine footwear or dancing ladies they are said to presently portray. As we breed, show and pedigree our botanical pets, some may even “learn” to resemble puppies.
James Ph. Kotsybar is an accredited judge of the American Orchid Society and Vice-Chairman of the Pacific South Region. He is co-owner of Chaotic Exotics (orchid nursery). He is an internationally published writer, teaches orchid horticulture at Allan Hancock College and is the founding Board Member and Advisor of California’s Coastal Valley Orchid Society.

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