The loss of a species, whether it is animal, insect, or plant, is not a laughing matter. Such losses have the potential to impact an entire biosphere, by depriving other species of a food source, by allowing a prey species to flourish when its natural predator dies, by depriving humans of a potential source for a life-saving drugs or novel biological compounds, or perhaps by just removing a touch of beauty from the world around us.
That said, Mother Nature is a harsh mistress and, even without the impact of man, millions, if not billions, of species have gone extinct over the millennia. From dinosaurs to trilobites, many species have passed from this world, leaving only bones or cropolite to mark their passage. Ignoring the five major extinctions, where millions of species were lost in a geological “instant,” it is estimated that Nature eliminates roughly 10 species per year, what is called the natural extinction rate. Species that refuse to adapt to changing conditions, or that are prevented from changing by physical barriers, are ruthlessly eliminated to make way for newer, more adaptable creatures.
Mankind has accelerated this natural process through habitat destruction, the introduction of new predators or competing species into previously protected habitats, and/or over-hunting. As a result, the current extinction rate estimated to be roughly 10 times the natural extinction rate, or roughly 100 species per year. Nature has no pity, and whether the change is “natural” or manmade, adapt or die is the only operative rule.
And while each and every species lost is a tragedy of unknowable proportion, we shouldn’t lose perspective. We discover about 15,000 new species every year. Some of these have been around a long time, but were previously unknown and undocumented. Others, such as the Faeroe Island house mouse or the Central European blackcap finch have speciated in recent times and represent truly new and unique species. Either way, we are gaining new species, even as some are lost.
For instance, in the last two years, we have seen three mammals, the Eastern Cougar (U.S.), the Japanese River Otter (Japan), and the Western Black Rhinoceros (West Africa), declared extinct. During that same time frame, several new mammalian species were discovered, such as the Toothless Rat (Indonesia), Sundaland Clouded Leopard (Malaysia), Saola (small deer, Vietnam), and a new dolphin (Australia), plus a cache of eight new, but yet unnamed, mammals (monkeys, possums, shrews) from the Peruvian Andes.
On a global scale, it is estimated that we currently have about 1.2 million documented species, but that the real number of species, documented or not, is about 8.7 million. When placed in that perspective, the loss of a hundred or less in small. Particularly when many of those lost in recent times where teetering on the edge of extinction prior to discovery.
The data does not exist to say, with any certainly, whether or not species extinction is higher than the rate of new species creation. Certainly, mankind has played a role in the loss of some species through over-hunting, habitat destruction, or introduction of competing species. But we have also played a role in the creation of others through our effects on habitat or the introduction of new species into isolated ecologies.
As we continue to discover new species, and chronicle the loss of others, perhaps the most important observation we can make is that nature is in a continual state of change and evolution, with new species coming into existence to meet the challenges of new environments, and old ones disappearing when their particular adaptations no longer suit the world around them. Those species that are successful are those which adapt and exploit the changes around them, while those that try to live in an environment that no longer exists soon perish.
It is a lesson of which we, as just another species, should take heed.