Paul Ehrlich: Surviving the Sixth Mass Extinction

As an environmental science student, there are a couple of seminal works that you are immediately introduced to, and see resurface in every class. From E. O. Wilson‘s theory of island biogeography, to Thomas Lovejoy‘s concept of biodiversity, to Michael Soulé‘s emphasis on conservation biology. I’ve had the privilege of attending talks by these individuals who are outstanding in their field thanks to the Nicholas School in the past years. This year was no different with Dr. Paul Ehrlich as the 2016 Ferguson Family Distinguished Lectureship in the Environment and Society speaker.


Dean Jeff Vincent introduced Dr. Ehrlich, recounting their time at the Beijer Institute of Ecological Economics, in Sweden, followed by our own Dr. Stuart Pimm, who has collaborated with Dr. Ehrlich for a long time.

His charisma was immediately evident as he took the stage and gave a true lecture: one without any PowerPoints, almost a rare thing nowadays. But with it, he fully captured the audience as he spoke about environmental disasters such as soil toxification, extinction of endemic species, and the immense risk of nuclear war. These were issues he felt that politicians often overlook and too linearly focus on climate disruption instead.

Together, all this human-induced activity has brought about a biodiversity crisis: the sixth mass extinction. In a brief history lesson, he highlighted that none of the previous mass extinctions are thought to be caused by a single-species. Referencing Dr. Pimm’s research where the current extinction rate far exceeds background levels, he concludes that without a doubt, we are bringing on a new mass extinction.

img_2312Given the current election fever, a few humorous jibes at presidential candidates were thrown, particularly those who do not believe in climate disruption or care about extinction. To me, the lack of discussion on environmental issues in all three presidential debates speak louder about the priorities (or lack of) in the government.

Dr. Erhlich pointed out that with the changing climate, species are either unable to adapt and go extinct, or evolve, a process where genetic variation is key. Agriculture, thanks to human cultivation of only particular strains of plants, is highly homogenized. Consequently, it is not just abstract concepts of biodiversity that is at risk, but our global food security. Of course, the growing human population does not help.

He admits that there are many things we have no information on. Primarily, micro-organism diversity remains largely unexplored, as is the weight of the role they play in the ecosystem, from cycling nutrients to beneficial interactions with organisms. Regardless, he emphasized that by habitat destruction alone, we know that species are being lost as their niches are gone. With this, he notes the shift in the scientific community where researchers have gone from trying to avoid collapse to studying how to recover from collapse.

Yet, even when we know the science of how much trouble the global environment is in, change does not occur without reciprocal action in the social sciences. It is for the scientists to tie with the humanities to recognize and implement changes, such as the empowerment of women for sustainable populations, and equitable distribution of food to resolve world hunger.


The issue that lies at the heart of how we treat the earth is the idea of infinite growth, one that feeds overconsumption and exacerbates inequality in our inherently finite world. In a rousing conclusion, Dr. Erhlich proposes a global constitution, one that is sorely needed to maintain the existence of all cultures regardless of arbitrarily-defined national borders.

In the question and answer, I was particularly inspired when he called on young people to enter graduate careers keeping the public sphere in mind, and to be established in the social sciences even if you are pursuing scientific research. The need for interdisciplinary studies, such as many of those conducted right here at the Nicholas School, has never been greater.