It has been suggested that 99.9% of all the species that have ever existed on this planet have gone extinct. Given that there are about 1.8 million named species and an estimated order of magnitude more unnamed, this means that there have been 2 billion or so species that have existed on our planet since life began here 3.5 billion years ago. The numbers could be even higher when the full extent of microbial life on our planet is realized. Extinction prior to humans has been an ongoing process, considered part of the natural way of existence on this planet. Scientists have been able to characterize past extinctions and have concluded that there have been five major extinction periods since organisms began to diverge on the planet. Each of these five previous extinctions is presumed to have occurred as a result of natural consequences, like extreme geological change such as volcanism or asteroid impact.
In 1993, the Harvard biologist E.O. Wilson estimated that each year about 30,000 species go extinct. If you do the math, Wilson's estimate in the 1990s meant that three species went extinct every hour. Since this estimate, things have not gotten better but rather worse, and the impact of extinction on biodiversity on our planet can be described as extremely grim. The current rate of extinction is so high that some biologists call it the Sixth Extinction. My colleague Niles Eldredge has written extensively on the subject and points out that the current massive number of extinctions is different than the previous five. The current Sixth Extinction is different in that the source of the extinctions are almost entirely biotic—that is, caused by humans as a result of our changing the landscape, overexploiting wildlife, polluting the environment and challenging pristine environments with introduced species.
The problem begs our attention, and over the past several decades the discipline of conservation biology was birthed and matured. The immediacy of the problem has prompted scientists to call conservation biology a "crisis discipline" like cancer biology or infectious disease research. Crisis disciplines often work under the "desperate times call for desperate measures" principle. The problem is that most people don't understand just how desperate the times have become, nor what a "desperate measure" really is.
Take for example the recent suggestion that cloning (writ large) can be used as a conservation tool. This suggestion fits exactly with our current Western "throwaway" society. The idea garnered a lot of media attention after being suggested a few years ago, and it seemed like every month some critically endangered species was being cloned or a project was being announced that was targeted at an endangered species. Many saw cloning as a drastic measure whose time had come. While I do not want to disparage the intent of scientists who made this suggestion, I think it trivializes what extinction really is and gets us back to the importance of understanding just how intense our desperate times really are.
In addition to cloning, a large proportion of conservation biologists would rather be called conservation geneticists. This moniker points to the use of modern genetic technology to assay and screen populations that are threatened and endangered. The use of genetics to understand populations and to characterize variability has also been viewed as a drastic measure by many conservation biologists. It has been challenged by some conservation biologists as unnecessary, even to the point where it is called "conversation genetics" by those who are critical of genetics as a tool in conservation. Nevertheless, these genetic approaches are viewed by the public as drastic measures that, I guess, are soothing with respect to the crisis. It is easy for the public to say, as a result of these technologies being applied to conservation: "Hey, look, we are throwing everything we have at the problem!" But here is where the widespread lack of understanding of the current mass extinction comes back into the story.
My colleague Mike Novacek has suggested that much of the problem is on the shoulders of educators who have failed to make clear the role of biodiversity in a healthy planet. The general public's lack of knowledge about what extinction is can be demonstrated by an interesting survey that City College of New York researcher and educator Yael Wyner has conducted. In the survey she asked over 1,500 New York area undergraduate students if the current demise of the panda in China is natural selection. The obvious answer to anyone who has studied evolutionary biology and the process of natural selection is a resounding "No stupid, it's us." However, nearly 50% of the students have answered that it IS natural selection, and a large proportion of those who answer "no" cannot properly explain why. This is yet another way we are trivializing extinction: through the inadequate education of our students and the public in evolutionary biology. The fact that a majority of Republican candidates for President of the United States this year take on a biblical interpretation of diversity on our planet trivializes extinction even more.
Another colleague of mine, George Amato, has strongly argued that it all ultimately comes down to funding. When it comes to funding, the study of biodiversity is a weak sister discipline to the more reductionist approaches such as molecular biology and genomics. The piggybacking of biodiversity funding with business (the European Union has initiated a Business@Biodiversity program) or with basic science such as genomics or infectious disease research are examples of funding trends currently in place by government agencies. Two examples of the latter trend are the piggybacking of biodiversity funding with research on emerging zoonotic diseases and the so called "one health" initiatives; and The Barcode of Life program, which piggybacks biodiversity studies with genetic technology. By providing only marginal funding for research that could help to slow the rate of extinction, it is as if governments are trying to put a band-aid on a bullet wound.
What can we do? First, we have to resist thinking that technology will solve the problem of large-scale extinction. Technology will help us understand the problem better, but it is not the silver bullet. Second, we need to educate the general public better so that we all understand the immediacy and breadth of extinction. Finally, we need to get governments to focus on the problem. The longer biodiversity is underfunded and piggybacked with other disciplines, the more species appear in the rearview mirror.
Rob DeSalle, PhD, is a curator in the American Museum of Natural History's Division of Invertebrate Zoology and co-director of its molecular laboratories and a member of CRG's Board of Directors.