At the intersections of biology and society, scholars have long explored ethical, legal, policy, economic, and other social issues, while also placing emerging science in the context of history and philosophy of science. One tradition has focused on the impact of scientific developments on society, reflecting on eugenics, recombinant DNA, reproductive technologies, human subjects experimentation, genetically modified foods, and other issues in largely reactive ways. Others are trying to anticipate where the science will be going and to outline issues that society is likely to face. Synthetic biology and technologies such as human reproductive cloning raise additional questions about whether we should forbid some science altogether. Stem-cell research or genetic engineering of food and people raise questions about appropriate regulatory responses. Experiments with pathogens and sequencing genes of dangerous organisms raise questions about control of knowledge. The National Science Foundation's Program on the Science of Science Policy explores issues of how science policy gets made and what factors influence the decisions.

Astrobiology falls into this complex world of biology and society, and here I ask: “Is there anything new under the Sun?” Or, more precisely, “Is there anything new under and beyond the Sun?” Have we already heard all the issues and are now just applying them to astrobiology in particular? Or are there special features of astrobiology that call for new thinking or raise new questions? Providing answers requires thinking about the presumed domain of astrobiology, then its implications, which in turn benefits from a look at the context of issues of biology and society more generally.

The domain of astrobiology

NASA defines astrobiology as “the study of the origin, evolution, distribution, and future of life in the universe.” Further: “This multidisciplinary field encompasses the search for habitable environments in our Solar System and habitable planets outside our Solar System, the search for evidence of prebiotic chemistry and life on Mars and other bodies in our Solar System, laboratory and field research into the origins and early evolution of life on Earth, and studies of the potential for life to adapt to challenges on Earth and in space” (NASA 2014a). The “astro” is only part of the story, which includes the origins and evolution of all life.

As part of the 2009 Darwin celebrations, we have seen the emergence and widespread acceptance of a standard narrative of the history of evolutionary biology that construes a more or less direct line from Darwin to present-day evolutionary developmental biology, or evo-devo (Mayr 1982; Larson 2004; Carroll 2005; Zimmer 2006, 2009; Ruse and Travis 2009). It is a story of completions and syntheses that not only celebrates Darwin’s genius but also implies an implicit progression of ideas, with inclusion of new empirical facts and methodological approaches within the general framework of Darwinism leading to an increasingly more complete understanding of the evolutionary process. This narrative involves both scientific and public discourses. It can be found in textbooks of evolutionary biology and in popular accounts of evolution; it is also the basis the many efforts to construct a more inclusive evolutionary worldview.

But the standard narrative “From Darwin to Evo Devo” is also woefully incomplete as it leaves out several important traditions within the history of evolutionary biology (Laubichler and Maienschein 2007). These neglected traditions are not fringe ideas with no relevance to current understanding of evolutionary processes that can therefore be relegated to the dustbin of history. Quite the contrary. The ideas and approaches that are part of a complementary tradition – namely, to explain the evolution of organisms in reference to the developmental mechanisms that first generate phenotypes and phenotypic variation – have informed some of the most important current evolutionary biology research programs, those in developmental evolution (devo-evo) and synthetic experimental evolution (SEE) (Wagner, Chiu, et al. 2000; Davidson 2006; Davidson and Erwin 2006; Laubichler 2007; Erwin and Davidson 2009).

When philosopher of biology Michael Ruse moved from Guelph, Ontario, to Florida State University, a very good thing happened for our understanding of the conceptual, historical, and philosophical foundations of biology. Ruse became the William H. and Lucyle T. Werkmeister Professor, which brought with it an endowment that allowed him to organize conferences on a regular basis. As usual, Michael Ruse lost no time, and the resulting series of conferences has brought together biologists, historians, and philosophers in lively discussion of a number of important topics. A favorite image of those events is that of Ernst Mayr, sitting in the boat during a swamp tour on a drowsy Florida afternoon. The aging but ever-intense Mayr seemed to be dozing, when suddenly he pointed and declared a noteworthy bird, then another, and another. That led to a discussion of whether biodiversity is declining; then to philosophical questions about how we count diversity; and finally to ethical and policy questions of why we care. Other conferences have led to debates about science and religion. And so on.

In 2005, a group of leading biologists joined philosophers and historians for four days of thinking about form and function. For this meeting, Ruse followed his usual approach. He provided the general theme, brought together a mix of enthusiastic scholars, and waited to see what happened. In this case, it was something very interesting.

Because of recent public excitement about cloning and embryonic stem cell research, more people than just developmental biologists are busily talking about embryos. Human embryos are central players in proposed legislation at state, federal, and international levels. But what is meant by an embryo? Rarely is the term defined or defined clearly. Yet the term is used in quite different ways and has evolved over time.

How have meanings changed, and for what reasons? What is the relationship between public and scientific understandings of embryos? Here, the focus is most directly on evolving understandings of the biological embryo, including recent shifting public meanings. In each case, both metaphysical and epistemological considerations are important. Yet only after the emergence of in vitro fertilization did the embryo become an object of significant ethical concern, and only with cloning and human embryonic stem stem cell research was it widely seen as an object of social concern. This essay considers the changing understandings of embryos.

Since at least 1771, with the appearance of the first edition of the Encyclopedia Britannica, the embryo has been seen as the earliest - and undifferentiated - stage of an individual organism's development. The embryonic stage was clearly separated from the fetal stage, with the first giving way to the second as form gradually emerged from unformed matter.

Here, by Chapter 196 of a volume exploring the endothelium in medicine, it has become clear that this is an astonishingly diverse and far-reaching subject. Identified for the first time only at the end of the nineteenth century, the once seemingly simple and passive cell layer is now understood to represent a dynamic system that reflects and determines much about health and function for humans and other vertebrate species. This collection of chapters shows how far we have come in our understanding, and also how rich the opportunities are for further study and more effective translation of our understanding into clinical practice.

There is great virtue in bringing together all these topics that would normally reside in the archives of separate disciplines. We have gained many different perspectives of what the endothelium is and how endothelial cells (ECs) come together as a functioning system. By reflecting on the way the endothelium develops and by comparing phenotypes across different species, we gain insights into the alternatives available and what any particular developmental pathway means for the organism. This helps us understand the endothelium as a highly evolved, integrated system. The system is by no means perfect. Rather it is an interlocking “bundle of adaptations,” some of which were born of trade-offs that are no longer applicable. Indeed, the extreme path-dependence of evolutionary change has undoubtedly engendered design flaws that render the modern-day human endothelium highly vulnerable to disease.

The use of metaphors to conceptualize the endothelium is a powerful tool for understanding an otherwise hidden and under-appreciated entity. We hope that the reader will agree that the analogies between endothelium and weather, landscape, and urban design are at the same time provocative and illuminating.

The endothelium is only now beginning to gain acceptance as a physiologically relevant organ with potential clinical significance. Yet the cell layer called the endothelium was first identified well over a century ago. In this chapter, we explore the circumstances leading to the slow recognition of the endothelium as a system with untapped diagnostic and therapeutic potential. We trace historically important steps toward increased interest in the endothelium, beginning with ancient discussions of the heart and blood vessels, and the conviction that blood derives from nutrition and is continually used up by the body. We see that, in Western medicine, the dominant culture of the Catholic Church impeded new discovery and instead emphasized reliance on accepted ideas for nearly 1,500 years. Only in the context of the Scientific Revolution of the seventeenth century could anatomists such as William Harvey challenge prevailing dogma and reach the conclusion that blood circulates and that it does so through a system of connected vascular vessels.

In this chapter, we examine those contributions and the developments that followed, slowly and gradually, the rise of new technologies for observation and the framing of new questions. We ask what caused researchers to focus on cells and tissues, and then, during the last part of the nineteenth century, to identify endothelial cells (ECs) as a unique structure, distinguishable structurally, physiologically, and developmentally from the epithelium that researchers initially had seen as closely connected to it. Then, we explore what implications the identification and naming of this particular set of cells had for the biomedical sciences.