By the late 1800s, many natural historians assumed that humankind had found and described nearly all of the species that lived on Earth. The year 2012 offered further evidence of how wrong they were -- and, also, how much more is left to find.
Scores of new species were discovered in the past year, just as they have been every year in recent memory. Our ability to distinguish among species has gotten better and better (in part, through the use of DNA technology), as has our ability to put trained biodiversity scientists in previously out-of-reach locales where "new" species exist undiscovered. Species discoveries are still happening every day all over the world. One is probably happening while you are reading this sentence.
I suppose you can't blame those early botanists and zoologists for assuming that they were at the vanguard of a golden age of species discovery through which the checklist of life on Earth was to be completed. The prevailing sentiment of the time was that Earth's biodiversity was a divine puzzle that was meant to be solved -- and well within reach of solving.
How were they to know how vast the pool really was -- and that thousands of different species might inhabit every verdant corner of the globe? Before the invention of the microscope, how could we possibly imagine that millions of species were all around us (and inside of us), just out of the view of our limited ability to see them? Or that entire biological communities were living in the impossibly deep valleys of the ocean floors where light never penetrates?
Some might think that by 2012, however, we could have found all of the plants. Plants don't move to evade capture, or bite you when you catch them. Unlike microbes, they aren't invisible without the aid of a lens.
Yet, a quick search using Google Scholar would tell you that more than 150 new plant species were published in academic journals in 2012. I assume that the true number is a bit greater than that. Heck, the single October-December issue of Systematic Botany had 14 new species in it, alone -- in addition to the most popular botany story of the year, a new genus of ferns called Gaga (named, of course, for Lady Gaga).
Botanists described all sorts of unusual things from unusual places this past year. Among them are two new leafless grass-like plants from the fynbos region of South Africa, a new orchid from Cuba, a new wild ginger from India, two new forget-me-nots from New Zealand, and a new loquat from China. Multiple new species were described from biodiversity hotspots we are still only beginning to survey, like the rain forests of Borneo, the Western Ghats of India, and the eastern slopes of the Andes. More reports of new species came out of wild habitats in places like Iran, Colombia, Australia, Haiti, Gabon, Taiwan and the southwestern U.S.
We also found new things from right under our noses: like a new crocus in Turkey, a carnation in Russia, or the new Monstera from Honduras that was already commonly used by locals to weave into hats. In 2012, we even found three new species of dandelion (two from Italy and one from Scotland).
The truth is that we are not even close to knowing every species on Earth. When the organisms upon which most terrestrial ecosystems are built, the plants, are still not fully described, we can only guess at how many other unknown and unnamed organisms are still out there.
So, what if we keep up our currently rapid pace of discovery? Can we still solve the puzzle of Earth's biodiversity? All things being equal, perhaps we might. But the trouble is this: The rate at which we find new things is still slower than the rate at which things are being lost. Species go extinct before we even know they are here with us.
One of the species described this year, a plant from the coastal shrublands of Brazil, was considered endangered before it even had a name. Just a couple of years ago, a botanist used a herbarium specimen at Kew Gardens to describe a brand new wild eggplant from Africa -- and, after much searching of its historical range in Tanzania, immediately declared it to be extinct.
What to do about this? Obviously, there are many actions we might take to both stem the tide of human-influenced extinction and hasten our discovery of who is out there. But one thing that would really help with the latter problem is training more biodiversity scientists. Simply put: We need more people to spend more time discovering Earth's species. We need more people to study the plants... and also nearly every other living group -- from rodents, frogs and fungi to mayflies, diatoms and slime molds.
As I write, there are millions of species out there in the wilds awaiting a visit from a trained eye. And, believe it or not, there are thousands of specimens already in museum collections that represent unknown things... but there aren't enough trained scientists to work on them.
Who will step up and recognize these mystery critters?
The hours are long and you probably won't get rich, but becoming a biodiversity scientist could mean you get to name some new species (almost) anything you want to -- and you have a high likelihood of being recognized as the world's expert on whatever group you choose to geek out on. With the right training, a sharp eye, and a good work ethic, you can go down in history as one of the greatest mussel taxonomists, orchid specialists, or beetle biologists who ever lived. How many professions can offer a carrot like that?
Oh, and there is also the small matter of helping to save a little bit of life on Earth.