At the beginning of the new year in a new century that has witnessed some of the most profound changes in biomedical science, it seems important to consider the meaning of what we have discovered and whether our views of the new powers we have acquired are perhaps simplistic. Certainly, our view of how life on this planet evolved –and of our relative importance in the vast chain of evolution- is one of the most important topics on our list. We have just passed the 150th anniversary of Darwin’s great contribution to our understanding of evolution; what he made seem so transcendentally simple is, in fact, more complex that we ever imagined. Furthermore, in most people’s view of evolution, man is the final result of a long, linear process, the qualitatively unique center and summit of created life on the planet. This notion of man as the most richly endowed and therefore the most valued form of life on earth is at the very heart of an anthropocentric notion of the universe. As Lynn Margulis, University Professor in the Department of Geoscience at the University of Amherst, who died recently, put it,
“One widely held unstated assumption is the great chain of being. It defines the venerable position of humans as the exact center of the universe in the middle of the chain of being below God and above rock. This anthropocentric idea dominates religious thought, even that of those who claim to reject religion and to replace it with a scientific worldview. For the Greeks, the chain joined a panoply of gods at the top to, in descending order, men, women, slaves, animals and vegetables. A substratum of rocks and minerals occupied the lowest link. The Judeo-Christian version allowed slight modification: people, above animals, were positioned a little lower than the angels. Man, of course, was indisputably and obviously superseded by the Almighty.”
Margulis fiercely contested this notion of the unique value of man and of our view of all other created life as taking its value from the degree to which it resembles ourselves. Her revolutionary theory of how we evolved began with what she termed the lateral transmission of genes between bacteria that fused; at the dawn of life, these one celled organisms absorbed free living elements like mitochondria and choloroplasts and by means of vertical transmission of their genome, as well as lateral transmission with adjacent cells, developed progressively into the panorama of living things present on the planet today. She stressed the fundamentally and equally important role of all life in evolution, and called the process by which life evolved symbiosis. She pictured the world as bristling with life in all forms: “not only are our guts and eyelashes festooned with bacterial and animal symbionts, but if you look at your backyard of community parks, symbionts are not obvious but they are omnipresent.” She stressed the late arrival of humans, reminding us that the first bacteria, which probably resulted from the strike of an electrical atmospheric charge on inert chemicals, probably originated over three billion years ago. Thus, she says, the earliest forms of life were neither plant nor animal. Each reproductive unit was part of a huge continuum of equally important, active elements. Rather than considering bacteria as disease-causing foes to be extinguished she asks us to think of them as colleague and ancestor. She explains that we are not simply unique collections of differentiated cells, but the product of vast colonies of microscopic symbiotic organisms, themselves mutating, that inhabit us and whose activity maintains and modifies our bodies:
“Our bodies are built from protoctist sex cells that clone themselves by mitosis., Symbiotic interaction is the stuff of life on a crowded planet. Our symbiogenetic composite core is far older than the recent innovation we call the individual human. Our strong sense of difference from any other life form, our sense of species superiority, is a delusion of grandeur.”
In Margulis’ view, the surface of the earth in a continuous blanket of organisms that constantly interact, exchange genetic material and continuously modify our environment and our very selves. Margulis called this living, evolving colony “Gaia”, the ancient Greek name for Mother Earth. She defines Gaia as “the series of interacting ecosystems that compose a single huge ecosystem at the Earth’s surface.”
In reading the literature about chimera and the relative importance of other species beside our own, the term, “moral value” recurs again and again. The human is considered to have the highest moral value, and those animals which most closely resemble him, significant moral value simply as a derivative of that similarity. The Institute of Medicine (IOM) has recently proposed , essentially, that the animals who most resemble us, specifically the Great Apes, should receive special consideration and wherever possible, exemption from serving as research subjects: the more an animal has human-like attributes, the greater its “moral value”. Indeed, NIH Director Francis Collins himself, commenting on this National Institutes of Health (NIH) –sponsored monograph , wrote:
“Chimpanzees are our closest relatives in the animal kingdom, providing exceptional insights into human biology and the need for special consideration and respect.”
Thus, chimpanzees ought to have particular consideration as a research subject, the NIH and the IOM monograph assert. The unspoken derivative of this idea is that the less like us a living species is, the less should be our concern about appropriating it for scientific experimentation. Nowhere in the reports about the NIH-sponsored IOM monograph was the reason for commissioning the report; why the chimpanzee is singled out for special consideration and by whom is unclear.
To me, at least, this view of a kind of graded value for living forms on the planet is skewed and simplistically asserts that what we can see and even more, what is recognizable as like us is more deserving of protection and regard. One’s concept of how life evolved –and continues to evolve- is very relevant to whether or not one holds to this tenet. As Margulis herself put it:
“All beings alive today are equally evolved. All have survived over three thousand million years of evolution from common bacterial ancestors. There are no “higher” beings, no “lower animals,” no angels and no gods….Even the higher primates, the monkeys and apes, in spite of their name (primate comes from Latin, primus, “first”) are not higher. We Homo sapiens sapiens are not special, just recent: we are newcomers on the evolutionary stage. Human similarities to other life-forms are far more striking than the differences. Our deep connections, over vast geological periods, should inspire awe, not repulsion.”
This last sentiment was echoed by Nobel Laureate Marshall Niremberg in one of our last conversations before his death. He told me that one of the most important insights of his life, which he had just related at a conference at the Vatican at the invitation of Pope Benedict XV, was the fact that the genetic material of all created life was stunningly similar, with only miniscule differences between species. He said that it made him feel a special kinship with the rest of creation to realize this; one he had never experienced until this insight, which would not have been possible until the discovery and description of the human genome—just over a decade old.
Certainly during her lifetime, Margulis’ view of the essential importance of all living things, and their crucial role in continuously fashioning and refashioning the creatures of the planet in all their complexity, was controversial. But our view of ourselves as the center and chief achievement of the evolutionary process should be controversial too. The Institute of Medicine Committee would, if challenged, probably urge a careful consideration for us to conduct research on all living things after careful consideration of the appropriateness of what we do. Certainly the same tenets they set forth for the protection of the great apes would serve for all forms of life we use of investigation: as the IOM report itself states, we should be guided by three principles in considering the use of other life forms in research:
- That the knowledge gained must be necessary to advance the public health.
- There must be no other research model by which the knowledge could be obtained, and the research cannot be ethically performed on human subjects; and
- The animals used in the proposed research must be maintained either in ethologically appropriate physical and social environments (i.e. as would occur in their natural environment) or in natural habitats. “
I find the current NIH prohibition of research on the great apes until further consideration is based solely on the idea that this animal was singled out because we recognize it as “most like us”. Certainly other forms of life deserve the same careful consideration the IOM urges for the chimpanzee. As Margulis put it:
“We need honesty. We need to be freed from our species-specific arrogance. No evidence exists that we are ‘chosen’, the unique species for which all the others were made. Nor are we the most important one because we are so numerous, powerful and dangerous. Our tenacious illusion of special dispensation belies our true status as upright mammalian weeds.”
Biomedical research on all forms of life is completely justified if we give sufficient consideration to the three simple principles the IOM advances. But those principles should apply to all life forms and receive thoughtful attention –and answers- from any of us involved in investigation.
Margulis, Lynn “Prologue” in Symbiotic Planet. A New Look at Evolution. Basic Books 1998. P 3.
The Use of Chimpanzees in Biomedical and Behavioral Research. Consensus Study. Biomedical and Health Research. The Institute of Medicine. Jeffrey Kahn, Chair. Washington, D.C. 2010
Collins, Francis: Chimpanzees in Research: Statement on Institute of Medicine Report by NIH Director Francis Collins. Scinece Daily: http://www.sciencedaily.com/reseases/2011/12/111215145719.htm. Accessed 12/31/11.
Nirenberg M. The Genetic Code and Evolution. In Scientific Insights into the Evolution of the Universe and of Life, the Pontifical Academy of Sciences. Vaitcan City, 2009.