Taxonomy Within the Plant Kingdom - How it Works
Classification. This is a word that’s become somewhat taboo in recent times. Of course, it depends on the context you’re using it in, but generally speaking, the 21st century is not particularly kind to the idea of classifying organisms according to their attributes, physical features, and core biological purposes. Potentially problematic monologue aside, at least when it comes to plants and animals, binomial nomenclature, and evolutionary and physical attribute-based hierarchies are still a productive way to understand the vast and beautiful world around us.
This article will seek to answer various questions regarding the field of taxonomy and hopefully shed more light on why this is such an important aspect of scientific and biological discoveries. I intend to take you through the history of taxonomy, how it has changed since the first inception of the idea of classification, and a practical way to understand the field. I also intend to shed light on the processes and intricacies surrounding discovering a new species. I found that the easiest way to learn about scientific fields of inquiry was to immerse myself in the methods, thought processes, and implications involved in whichever field I’ve been interested in. I hope to inspire the same interest in taxonomy within you.
An Introduction to Taxonomy
There will be some among you who already have a decent idea of what taxonomy is and why it plays such an essential role in our understanding of the world we live in, but I hope to make those answers even simpler.
One thing I’ve often struggled with is that scientific fields like taxonomy are rarely explained in such a way that people without either a keen interest in Aristotelian philosophy or degrees in biology can understand what is being said. It’s as if there’s a massive disconnect between those who formally study certain subjects and those who don’t, and I haven’t found many sources that go so far as to explain the complex terms, ideas, and discoveries so that those with merely an interest in them can learn more about them. I, along with the other Bonsai Alchemists, am here to break down the walls of science and biology. My sledgehammer is primed, and my swinging arm is ready. So let us begin, shall we?
Before we can delve into the meat of taxonomy, we have to get clear on what it is. Most people know that taxonomy has to do with species, their scientific names, and differentiating between them, but if we take a look at the root of the word, as I often do, we can see exactly what it means.
Taxonomy, like many scholarly principles, is a combination of two Greek words, taxis and nomos. Taxis means arrangement, and nomos, law. From this, we can see that taxonomy relates to a law of arrangement. In fact, it is the law of arrangement in terms of living things. If we want to haul out the more scholarly definition of taxonomy, we might say something along the lines of ‘Taxonomy is the methodology and principles of systematic zoology and botany and organises living organisms into hierarchies of subordinate and superior groups.’ Simply put, using the definitions of the root words, we could say that taxonomy is a set of laws used to arrange all living organisms into different ranks, classes, species, and families.
This kind of arrangement makes it easier to examine relationships, differences, and similarities between various organisms and better understand how they fit into the natural world.
The Problem with Names
If you consider any names, we’ve been arranging living organisms into groups that are easier to understand for as long as we’ve been on this earth. Words like ‘worm’ and ‘fish’ date back to the early Middle Ages. They were first spoken by a group of Germanic tribes who came together to form the Anglo-Saxon confederation who settled in Britain from mainland Europe. These early tribes of man needed a way to differentiate one organism from the rest. And if you think about it, names are primarily introduced out of need, a need to understand, comprehend, and differentiate.
The word ‘fish,’ for example, stood as a way to differentiate between organisms from the land and those from the sea. There are, however, many problems with early nomenclature. For example, even though both starfish and sardines come from the ocean, as an organism with bones, a sardine has more in common with a human than it does a starfish.
There is also the issue of vernacular names or common names. If you want to sound scholarly, you might refer to these ordinary everyday names for organisms as trivial epithets. So many times, when conducting research, I come across organisms with names that contradict their nature. An example of this is how a flower known as the Confederate Rose has nothing to do with roses because it is actually a hibiscus. Another example is that a Ponytail Palm isn’t actually a palm.
In reality, it’s a succulent plant, closer in nature to aloe or agave. Based on these examples and many others, we can see that vernacular names sometimes muddy the waters of classification and are therefore not adequate as a formal system. This realization creates a need for a better way of naming living organisms. It creates a need for a deeper understanding of how all of the organisms around us relate to each other. It creates a need for taxonomy.
The History of Taxonomy
When you first delve into taxonomy, it’s likely that you’ll run into two names ahead of the rest; Aristotle and Linnaeus. These two men are seen as the fathers of modern taxonomy due to their respective roles in the development thereof. Aristotle was the first to attempt to classify all living organisms, and Linnaeus united the many different classification systems that existed when he was the next big thing in science and created the modern idea of binomial nomenclature as we know it today.
However, these two brilliant men were not the first time humanity has formally tried to categorize living organisms. For that story, we have to go all the way back to ancient China.
One of the first mentions of an early system of natural classification is of a Chinese catalog containing 365 different species of plants with medicinal uses. While credited to Emperor Shennong, a Chinese head of state of mythical proportions around 2700 BCE, it is widely accepted that the catalog was, in fact, written at the beginning of the first Millenium. Now, this wasn’t a full-on classification of every living organism that the Chinese community of the time was aware of; it was a very specific catalog of purely medicinal plants.
As we mentioned earlier, the process of naming and categorizing the world around us originates primarily out of need. The most pressing need at that time in China seems to have been for a compendium of knowledge of sorts about plants that can be used to treat various ailments. They had no need for a hierarchy of all known animals, so they didn’t create one. Need is the primary driving force behind categorization.
We see a similar collection of writings on papyrus dating from around 1700 to 1600 BCE in Egypt. This, too, was a medical-centric collection of information on plants with medicinal uses. The incredible papyri contained the names of all the known medicinal plants, along with all of the ailments they were known to be effective in treating.
From there, we move on to ancient Greece and that very first name, Aristotle. Aristotle is widely regarded as the father of science, logic, and taxonomy. He spent a great deal of time on the Greek island of Lesbos, where he, like many of his Greek counterparts, had unbridled access and constant contact with the ocean. It was here, on Lesbos, that he is believed to have studied species far more closely than most in order to develop early versions of his writings. In his writings, he describes, in great detail, numerous proposals for natural groupings. Even though his groupings organized living organisms in order of simplicity to complexity, it’s important to note that his motivation was not evolutionary in nature. He was an incredibly advanced individual by all accounts and is widely regarded as being ahead of his time.
Aristotle had such an incredibly intricate knowledge and understanding of the natural world and knew, for instance, that dolphins, porpoises, and whales have characteristics that put them closer to other mammals than to fish, even though they shared a habitat with the latter. For reference, so that we can keep in mind how the system of taxonomy has changed, here is an overview of how Aristotle classified living organisms:
With red blood (Vertebrates)
- Viviparous quadrupeds (land mammals)
- Oviparous quadrupeds (reptiles and amphibians)
Without red blood (Invertebrates)
- Shelled animals
- Plant-like animals
- One woody stem (trees)
- Many woody stems (shrubs)
- Soft stems (herbs)
Aristotle’s classification efforts remained the dominant method until around the 19th century. At its core, the Aristotelian method was one classifying living organisms by their intrinsic nature instead of simply how they looked, as was the case with the Anglo-Saxons. It required the intense examination of an incredible amount of specimens and establishing constant characteristics. This often led to discarding variable characteristics as they were seen as outliers or accidental, not essential to the deeper understanding of organisms as necessary for classification. Put simply; he focussed on what made an organism what it was, those characteristics that were essential to its survival and immutable.
When the 12th century came around, a resurgence of the ancient Chinese and Egyptian need to classify plants used in medicine led to new works being developed that collected, illustrated, and described medicinal plants. Soon, encyclopedias started emerging that even attempted to group plants together based on their perceived similarities and practical efficacies against known maladies. In 1543, the newly flowering biological Renaissance led to works such as Andreas Vesalius’s Treatise on Human Anatomy, and in 1545, the first university botanical garden was founded in Padua, Italy. Suddenly botany was the next big thing in the biological science spheres, and as was discovered, Aristotle was far more suited to the classification of animals. He is believed to be, at heart, a true early zoologist.
Enter Carolus Linnaeus
One man who was not a zoologist by many accounts is the second father of taxonomy, a Swedish botanist, Carolus Linnaeus. Linnaeus burst onto the scene during a time when botany and zoology were flourishing. Shortly before Linnaeus, there had been John Ray, who added to Aristotle’s then-staple classification systems to differentiate between monocotyledonous and dicotyledonous plants. Simply put, he noticed a difference between plants that grow with one initial leaf and those with two. I expand on dicotyledons in How to Identify hibiscus.
Linnaeus and Aristotle were both men ahead of their time, thinking about aspects of zoology and botany that other men of science of the time simply could not. While Aristotle is the father of taxonomy, Linnaeus is the father of modern taxonomy; that is to say, he is the curator and creator of the system of classification we use today, give or take a few changes.
Even though Aristotle is credited for the creation of binomial nomenclature, it wasn’t as widely practiced, and some organisms ended up being known by seven or eight Latin words. In the case of the humble tomato, its formal name was Solanum caule inerme herbaceous, folis pinnatus incisis, racemis simplicibus. Nine words. Nine very long, very l
Latin words. While Latin was the language of most higher education institutions of the time, how on earth would we have navigated scientific inquiry and indeed our articles if we had to allot nine Latin words for every single species of plant we discuss on this blog? You’d be bored, we’d be bored, and I doubt anyone would actually still be interested in botany apart from those who expressly study it through formal institutions.
Carl Linnaeus, as he is sometimes referenced, was appalled by the naming conventions in place as pertained to plants. In his own words, Linnaeus’ shuddered at most botanical names given by modern authorities.’ One of the first things Linnaeus did was find a better, more efficient, and more consistent way to use binomial nomenclature. Binomial nomenclature here means a convention of naming organisms that places emphasis only on the family and species of that organism. So, in a broader sense, Linnaeus drew on the work of his predecessors and contemporaries and simplified the system in place for generations to come.
Another thing that Linnaeus changed for the better is introducing a standard hierarchy for classifying life. The order of which is as follows:
This is a distinct and considerable change from the taxonomic tree or phylogenetic tree that Aristotle created.
This brilliant force of nature within the biological disciplines also wrote a series of books. In them, he not only categorized plants more minutely than Aristotle, but he also included workable keys so that those reading his books could classify and identify plants as well. He is known for creating his hierarchy of the natural world based on the smaller parts of plants and flowers that had, until then, been discarded and neglected.
One fun fact that I enjoy about Carl Linnaeus is that he was born without a surname. Essentially, in his time, surnames were primarily used for those of noble birth, which Linnaeus was not. The story goes that he arrived at the university at Uppsala and was asked to provide a surname for registration purposes. Seeing as he had no surname to speak of, he created one. He named himself after a tree he was fond of that grew abundantly in his hometown. With one flick of an 18th-century pen, he became Carolus von Linne, now known as Carl Linnaeus.
Linnaeus also attempted to create a modernized system of classification for animals, but this was far less of a success than he had with plants. As stated before, Linnaeus was a botanist, not a zoologist. Without elaborating too much on animals, he ended up with a system that gave animals more names than they previously had, which was his problem with the systems already in place pertaining to plants in the first place.
Since Linnaeus, we’ve identified more species than would fit on his phylogenetic tree, so we’ve had to make alterations. In fact, to account for the incredible number of organisms discovered since his time, we’ve had to add three new ranks above class, the former highest rank of natural classification. So today, the phylogenetic tree of taxonomy looks as follows:
True to Linnaeus’ original pursuit toward true binary or binomial nomenclature, we currently only refer to the genus and species of an organism when naming them. This is how modern humans came to be known as homo sapiens, and one species of the dwarf-variety hibiscus became known as hibiscus aethiopicus. You can read more about that particular pretty flower in our comprehensive care guide for hibiscus aethiopicus.
A Practical Exploration of Taxonomy
In a previous article, How to Identify Hibiscus, I took you on a journey in which we discovered what hibiscus looks like in a practical sense. I used taxonomy as a basis for the journey, and we looked at what characteristics hibiscus has in order to understand the various structures and conventions that led to it being in its current position within the taxonomic classification system. I did this for two reasons.
First, I needed a more interesting way to answer the question of how to identify a specific plant other than a series of pictures of it accompanied by descriptions of its structure. That would have been an incredibly boring article, and I couldn’t see myself wanting to settle in and read it, so why write it?
The second reason is that I realized the taxonomic system places a lot of emphasis on the features an organism has. Thus, the best way to identify hibiscus, and teach you to do the same, was to narrow it down all the way through the plant section of the taxonomic system until I arrived at the exact plant I was trying to describe. In doing so, we learned that it has a five-petal arrangement, grows from two initial leaves, and features a central reproductive pillar where the stamens, anthers, and filaments are located. We learned a lot more on that journey, but those are typically the types of features you’re looking for if you’re trying to decide what plant you’re dealing with.
If you haven’t read the article yet, I’d recommend it, but I’m about to take a similar journey for another plant, one of my absolute favorites; the beautiful bougainvillea.
The Taxonomy of Bougainvillea as an Example
As previously stated, the taxonomic system consists of eight ranks called the phylogenetic tree or taxonomic hierarchy. As we go, you’ll see that the ranks become increasingly more specific, narrowing down on the features, functions, and core biological principles of a species until we reach the desired species, in this case, bougainvillea.
Domain is the most recently added rank and is the broadest. It organizes all living organisms into three groups, namely, Archaea, Bacteria, and Eukaryota. Bacteria is fairly self-explanatory; we all have a basic understanding of what bacteria are. Archaea is not much more than a more biologically sound term for single-celled organisms. Eukaryota is the word used to describe everything else that is neither a single-celled organism nor bacteria. Seeing as we know that bougainvillea is not a bacterium, and it definitely has more than one cell, it stands to reason that it belongs in the Eukaryotic Domain.
All of the domains are broken up into different kingdoms. For the purpose of this article, we will be focussing only on the kingdoms of the Eukaryotic Domain. These are Plantae, Animalia, and Fungi. There is a fourth kingdom that exists to categorize everything that isn’t a plant, animal, or fungi; this kingdom is known as Prostata.
Here is where taxonomy gets a little more complicated. In the modern understanding of taxonomy, region plays a massive part in how many kingdoms people recognize. The United States and Canada technically use the six kingdom methodology:
Whereas in Great Britain, India, Greece, and Brazil, to name but a few, textbooks clearly denote only five kingdoms:
However, other research papers, biological reference material, and indeed the wider internet tend to focus on the four kingdoms we listed earlier. In reality, there is no lack of confusion where biological kingdoms are concerned, with some respected works citing the existence of up to eight. For the purpose of this article, however, we are focussing on one of the three kingdoms that don’t undergo any change no matter which system you subscribe to; Plantae. Within the plant kingdom, there are various Phyla.
Just as there are strongly worded disagreements where kingdoms are concerned, phyla are equally as hotly contested. There are formally 14 recognized phyla in the plant kingdom; these make up all of the plants in the known world. Each phylum uses a specific feature or function to create a distinction between itself and other phyla.
Essentially, the phyla separate mosses from plants with flowers, conifers from ferns, and cycads from ginkgo plants, to name but a few. However, there is still some confusion about what makes a phylum and what makes a class. The phylum we need to move into to carry on with our identification of hibiscus is the angiosperms. Unfortunately, even though angiosperm is a phylum on its own, you won’t find it on most 14-phyla lists. Instead, flowering plants, which is what an angiosperm is, are listed as belonging to the Magnoliophyta phylum, or Anthophyta. These are, in this case, the same group of plants. Magnoliophyta = angiosperm. In my opinion, angiosperm is the better word as it gives us much more information on what kind of plants we should expect to find within this phylum.
By now, you’re used to me breaking up a word to understand its meaning better. This is another one of those instances. Angiosperm is a word of Greek origin comprised of the root words angeíon (ἀγγεῖον) and spérma (σπέρμα). The former translates to vessel or bottle, and the latter means seed. From this exploration of the core terms, we can see that an angiosperm is a plant that has seeds encased in a vessel, which in this case is the flower itself. Now that we’ve discussed the phylum that bougainvillea belongs to, as it is a flowering plant that contains enclosed seeds, we can break that phylum up into its various classes.
Again, we can’t seem to agree on how many classes there are within the angiosperm phylum. Some subscribe to there being eight, while others believe there are only two. The system isn’t perfect, but it’s served humanity and curiosity well. For argument’s sake, let’s take the simplest path, which is that there are two classes of angiosperms. These are the monocots and eudicots. Eudicots are called dicots for short, so if you see the word monocot next to dicot, you’re on the right track, and in the right place, science just seems to have many words for one idea.
Whether a plant is considered a dicot or a monocot depends on whether it sprouts with one leaf or two. If you look at a bougainvillea sprout, you’ll see it boasts two little initial leaves before the plant grows and fills out. This means that it is in the eudicot or dicot class. Eudicot actually tells us much more about the plant than you might think. The full word is actually eudicotyledons, and the first two letters, ‘eu,’ mean true. Cotyledon means something with a cup-like hollow shape. Cotyledon is also the name used for the very first leaves a plant grows, and as we’ve established, bougainvillea has two of these. Cotyledons, as the first structure visible on the surface when the plant begins to grow, are usually part of the embryo or the seed of the plant. So we can see that the word eudicotyledon then refers to a flowering plant that grows two initial leaves that are part of its embryonic structure. Now that we have the class we need, it’s time to move on to the order.
Before we talk about order, though, it’s important to discuss what clades are. If you’ve done any kind of research into taxonomy, you’ll have come across the term clade. The confusing thing about clades at first glance is that they seem to appear everywhere. While all of the other groupings seem to nest into each other quite nicely, clades are all over the place. This is especially true for the taxonomy of plants. Here’s the simplest explanation I could come up with:
A clade is a subgroup with a very specific purpose. Clades basically group together variants of organisms within each group of the taxonomic hierarchy, provided that they share a common ancestor. While other groupings, such as class, order, phylum, and kingdom, are groups based on physical characteristics, clades only group together organisms with clear common ancestors by way of evolution. So, within the various classes of organisms, there are different clades that each share a common ancestor. Within those clades, we have other clades that further explore the common ancestry of organisms.
When dealing with bougainvillea, the order we’re looking for is that of the Caryophyllales. This is an order of approximately 37 families of flowering plants, 749 genera, and 11,620 species. Plants belonging to families in this order are primarily identified by the presence of anther wall development and vessel elements with simple perforations. Pollen is produced within the anther walls.
Vessel elements are essentially the building blocks of the plants in this order that help them transport water from their roots to other parts of the plant. This is a little bit more difficult than identifying other orders, such as the Malvales. There isn’t really any way, without a microscope or incredibly good eyesight, to see the presence of anther wall development or, much less, vessel elements. The picture does, however, get a little clearer when we move on to family.
The family in question is one of the 37 in the order Caryophyllales, Nyctaginaceae. This family, also known as the four o’clock family, is known for its particularly unique characteristics. The list of characteristics held by the majority of the Nyctaginaceae family is a rather complex list of attributes with Latin roots. As has become my modus operandi, we’re going to take each of these words apart to make sense of what is actually being communicated.
Here’s a description written with the traditional universally accepted scientific terminology, taken from ScienceDirect and an article concerning biochemistry, genetics, and molecular biology:
‘The Nyctaginaceae are distinctive in being trees, shrubs or herbs with opposite leaves, the flower(s) subtended by a calyx-like involucre in some, having a uniseriate (calyx, often petaloid), an annular, nectariferous disk, and a unicarpellous ovary with a single, basal, usually campy-lotropous ovule, the fruit an achene or nut often surrounded by persistent, accrescent calyx, forming an anthocarp.’
If you skipped over this 59-word long sentence, I don’t blame you. Once we discuss what all of these words mean, however, the sentence should make sense. Essentially, this is a broader lesson in trying to decipher the world around you. Every scientific term you’ve ever come across can be broken down into core concepts that you can understand with ease. Science and biology no longer have to be fields of inquiry reserved for those who study them formally. You can master this kind of content.
Taxonomy is such a vast, incredibly intricate system, filled with statements and sentences like the one above. But that doesn’t mean the knowledge contained within them is inaccessible. With that in mind, let’s take apart some words, shall we?
I’m starting with a list of the features mentioned in the statement taken from the article on ScienceDirect. This is to separate the most important parts of the sentence from the rest. Dividing content like this up into smaller, more comprehensible pieces is the best way to tackle most things you may not understand immediately.
- Trees, shrubs, and herbs
- Opposite leaves
- Sometimes subtended by a calyx-like involucre
- Uniseriate perianth
- Petaloid calyx
- Annular nectariferous disk
- Unicarpellous ovary
- Single, basal, often campylotropous ovule
- Often an achene or nut
- Sometimes surrounded by persistent, accrescent calyx
- Calyx forms an anthocorp
What a description. However, breaking the paragraph apart also helped us, in this case, to group the descriptions to better understand what exactly we’re looking at.
The basic form of this family is easy to understand. This is a family of plants that can be either trees, shrubs, or herbs. In the case of bougainvillea, we’re dealing with a shrub. Opposite leaves are also fairly easy to spot. The complexity comes in when we consider the flowers and fruits that the Nyctaginaceae family produces.
The first bullet actually perfectly describes bougainvilleas directly. Involucre is a word that here refers to the bracts of a bougainvillea shrub. The bracts are part of a vibrant, delicate structure that surrounds and encloses the actual bougainvillea flowers. This is what it means to subtend in botanical terms; to surround and enclose. The calyx is a structure commonly seen on many flowers. Located underneath the petals on adult flowers, the calyx is what we usually call the bud. Except, when the flower is open, the calyx looks like a small flower itself. The green petal-like extensions on the calyx at the base of the flower head are called sepals and, early in the flower’s development, enclosed it.
The wording of that part of the sentence makes it even easier to understand what we’re looking at. The description states that the central elements of the Nyctaginaceae family are not surrounded by a calyx but rather bracts that are ‘calyx-like.’ While many people view the bracts as leaf-like flower petals, bougainvilleas actually have small cream-colored flowers within the back structure. These flowers each have a calyx at the base of their petals.
The next bullet deals with the arrangement of the flowers of the Nyctaginaceae family. The perianth is the very outermost part of a flower, consisting of both the petals, which make up the corolla and the sepals making up the calyx. Uniseriate basically means that the calyx and the corolla are separate. This is clear on the bougainvillea shrub because it has three flowers within the outer bract structure, clearly denoting a separated perianth arrangement. Flowers of other families may have petals that are fused with the sepals; this is then called a biseriate perianth.
Next, we have the presence of a petaloid calyx. We won’t spend too much time on this one as it’s fairly easy to see. In terms of calyces, there are two primary types, those that are green and those that are vibrant and colorful. Green calyces are called sepaloid, and those sporting more vibrant colors, such as the hot-pink, red, yellow, and purple bracts of the beautiful bougainvillea, are called petaloid. This also refers to these bracts resembling petals.
An annular nectariferous disk is also a relatively easy concept to grasp. Annular refers to a circular or ring-like shape, and a nectariferous disk is simply a biological ‘disk’ within the flower that produces nectar.
The next term is a unicarpellous ovary. Carpel, here, refers to the pistil of the flower. The pistil, in the case of bougainvilleas, is a tiny pillar-like structure within the center of the small cream-colored flowers. The prefix ‘uni’ means one, and in this case, coupled with the term ‘carpellous’ to tell us that the flowers of this family typically have one pistil. At the base of the inside of the pistil, you’ll find the ovary. When pollen is deposited onto the pistil by a pollinator like a butterfly or a bee, the pollen grows downward into the base of the pistil to fertilize the ovary.
The last bullet pertaining to the flower is one so deeply buried within the flower that it won’t help you identify a flower in this family at face value. You’d have to dissect the flower for exposure to these parts. Essentially, the term campylotropous ovule refers to ovaries and seeds that are so curved that they bring the ends of the embryo really close together.
Bougainvillea does not bear fruit like other plants within the Nyctaginaceae family. Therefore, it would be pointless to discuss fruit within the context of this section.
If you now go back to that long sentence a few paragraphs up, you’ll notice that each and every one of those complex words and terms holds a wealth of information, giving you a better understanding of the flowering plants within the Nyctaginaceae family. You can apply this principle to any aspect of the taxonomic hierarchy and likely come up with a description that is easy enough to comprehend and leads to a better understanding of taxonomy and how living organisms are related to each other.
If we wanted to turn this article into a book, we could discuss the bougainvillea genus at a much greater length and do an entire sub-section of the genus’ various species. But this isn’t an article about bougainvillea. This is an article about how to navigate the complex and sometimes confusing world of taxonomy. Having successfully identified a flower all the way from its domain to its genus, I believe I’ve communicated that point. What I would like for you to take away from this is that taxonomy is a nesting system to try and determine how all life on earth is related to everything else. We can learn a great deal about botany and zoology by exploring the finer points of taxonomy, and I encourage anyone curious about any scientific or biological principles to pursue them with their entire being. Immerse yourself in that which you feel is above your level of cognitive ability because you’ll soon find that you are capable of so much more than you thought.
How Do Taxonomists Describe a New Species?
This is a question posed rather often by those new to the field. One thought newcomers often have is that new species aren’t really a thing anymore. We don’t see much of this field of inquiry publicized in the news or on social media. So people are often surprised to learn that over 2,000 new species of plants are discovered worldwide every year.
The next question, once the shock has lifted, is how on earth do taxonomists go about describing a new species?
There is a really intense, bewildering art to the work that taxonomists do. Describing a new species involves hours of dedication, research, sample collection, and classification, and it could not be a more important job within the scientific community. Taxonomists are largely why we have the depth of understanding of life, the universe, and everything that we do.
Below, we’ll take a step-by-step approach to how every single one of these approximately 2,000 new species each year is identified. This is far from the easiest job in the world, but I can only imagine how gratifying it must be to be able to contribute to human knowledge on this scale.
Step 1: Specimen Collection
Taxonomy is based upon specimen collection. The standard operating procedure for any taxonomist worldwide, with very few exceptions, is to collect a dead specimen of the potential new species of plant, shrub, or tree so that they can verify the species is, in fact, new. Specimens are also collected to make sure that there are physical examples available for future reference. This allows other scientists and botanists to compare the new specimen against future discoveries and makes it easier to verify whether they may be part of the new species in question.
All new species require what is known as a holotype. This is basically one individual type that future discoveries can be compared to in order to determine whether they belong to a particular species. These subsequently discovered specimens belonging to a specific species are known as isotypes and paratypes.
Step 2: Specimen Analysis
Every single step in this identification process is integral, but this is likely the most important step of all. Once you’ve discovered a suspected new specimen, you need to get it to a lab environment. This is so that the specimens can be prepared, examined, and stored in an appropriate way.
Step 3: Specimen Verification
Once you have the specimen in a lab environment, the potentially longest and most complex part of the process begins. This is the process of definitively determining whether the specimen you’ve found is indeed a new species of plant. This involves incredibly careful comparative analysis against specimens of potentially closely related species. This is usually supplemented by molecular and phylogenetic analysis. This means determining where exactly it could belong on the phylogenetic tree or taxonomic hierarchy.
This step usually also involves specialists from other institutions being called in to consult on the suspected new species, as well as the request to examine species from other collections as part of the comparative analysis. This step requires the most highly refined level of expertise in taxonomy, a resource that is sadly dwindling by the year. In fact, there are currently only a handful of taxonomists with sufficient expertise to work on the identification of a group of microscopic fungi that parasitize insects.
Step 4: Name the New Species
The next logical step, once you’ve verified that a specimen is indeed of a brand-new species, is naming the species. Technically, you can name this newly-discovered species after anything. There are species named after television shows, celebrities, catchphrases, and even the taxonomists themselves. What we would view as unique names, however, are far less common than you might think. Names are usually derived from details of the specimens’ ecology, geography, and morphology.
Step 5: Place the New Species in a Collection
Once it’s been named, it’s time for the confirmed new species to be placed into a collection. This collection has to be internationally recognized and relevant to the field of study within which the new species falls. So in the case of a new plant species being discovered, you’d need to submit it to what is known as a herbarium. These collections and displays play an important role in taxonomy for numerous reasons:
- They represent a secure, central depository where specimens can be stored appropriately for centuries. Today’s scientists benefit greatly from being able to examine species and specimens from hundreds of years ago. We’ve successfully extracted DNA from specimens that date back to the 18th century. This wouldn’t be possible without secure depositories.
- These depositories also represent a concentrated collection of the taxonomic expertise gleaned in various fields.
- Having massive, concentrated collections of similar species makes it much easier to compare potentially new species against those within close proximity to it in the taxonomic hierarchy.
Essentially, these depositories act as a one-stop shop for taxonomists and make it easier to perform the incredibly difficult work they’ve devoted their lives in service of.
Step 6: Describe and Publish the New Species
Once a taxonomist has done the necessary work, research, and in-depth analysis of a new species to confirm that it is, in fact, completely new, they need to present the new species to the wider scientific community in written form. This usually consists of papers published in prolific peer-reviewed journals, but specialist textbooks are also a sufficient format in which to announce their findings. Another popular choice is to submit your descriptions to Phyotaxa, a specialized mega-journal for new species discoveries within the context of botany.
Descriptions in taxonomic terms, as we’ve seen, are fairly standardized. You have to provide commentary on specific aspects and characteristics of your new species. This makes it easier for other scientists to compare the species against those already published. An immense amount of detail needs to go into these papers, and they sometimes can take several years to complete. This is largely because you need to secure formal recognition of your new species by an authoritative taxonomic board. The time frame in which you wait for a new species to receive the necessary approval is sometimes referred to as the shelf-life of a species.
This entire process is incredibly arduous, intricate, complicated, and time-consuming. But I feel it’s such a noble task and passion to take up due to the sheer importance of a functional categorization system like taxonomy.
Why Does Taxonomy Matter?
This is a question often posed when people are first introduced to the field. I remember sitting in a biology class in the 7th grade when the teacher gave us our first in-depth, formal lesson on taxonomy. She described its history and gave us a brief example of how the system functions, but the rest of the lesson was purely learning the system’s ranks in a parrot fashion. One of the first questions I wanted to ask was ‘why do I need to know this?’ I couldn’t understand how a scientific field this complex would ever affect my life.
Now, years later, I know. And the truth is it affects all of our lives in the most profound ways.
Global biodiversity is severely affected by the way we’ve interacted with this planet, its fauna and flora, and its resources since emerging from the evolutionary tree. We’ve dealt such harsh blows over the centuries to too many natural ecosystems to count, and with our greed at a seemingly all-time high, we don’t seem to be able to stop our reliance on that which destroys our planet.
Taxonomy is important for global biodiversity because of the vast amounts and types of information collected about each new species. We’re able to use this information on where a species comes from to determine how much danger the species is in where extinction is concerned. This, in turn, gives us the data we need to decide where to establish protected areas to conserve native species. We can also identify threats to biodiversity, natural or otherwise, and determine what steps can and need to be taken in order to combat these threats.
Taxonomy serves many other purposes as well. For instance, the knowledge gleaned by taxonomists can be used to determine the effect an invasive species of plant has on the indigenous species. This data also makes it possible to determine what concentrations of natural resources certain regions have available and what percentage of that can be used without posing a threat to ecology.
Essentially, taxonomy gives us access to vast stores of information that we can use to identify and work on solutions for problems, in addition to serving as a sort of encyclopedia for future discoveries. Taxonomy may be complex and sometimes difficult to grasp the first time around, but it is a field of inquiry that is essential to developing a better understanding of our planet and how we should be interacting with it.
Taxonomy: An Art Like No Other
Taxonomy is a fine art. It requires an eye for detail, an appreciation for the beauty of the world, and a keen, inquisitive mind capable of asking pertinent questions. This isn’t an art form suited to everyone’s abilities, interests, and ambitions, but it is incredibly noble nonetheless.
My hope is that you’ve enjoyed this journey through the intricately woven tapestry of natural knowledge that is taxonomy and that you’ve come away from this piece with a better understanding of why this field of study is so incredibly important. I hope I’ve been successful in making this subject a little easier to deconstruct, examine, and put together again in a way that makes more sense. I also hope to write more about taxonomy in the future and further break down the boundaries between formal education and general interest or inquisitivity.