This essay explores how the human biological self is socially constructed, and rejects various truisms that define our character. Rather than being stand-alone entities, the human biological self forms what biologists call “superorganisms” and what I call “poly-super-organisms.” Thus, along with prokaryotes , viruses, and other entities, we are combined in an inseparable menagerie of species that is spread across multiple bodies. Biologists claim that only males and females are organisms. As described here, however, human sperm and eggs are equally (...) entitled to that rank. Much about human reproduction is also socially constructed. For example, contrary to scientific wisdom, humans have always reproduced both sexually and asexually. Moreover, human life does not begin between conception and birth, and neither event creates new life. In addition, some cancer cells are organisms; they are contagious entities formed by asexual human reproduction. Finally, while science universally describes humans as being living entities, accumulating evidence makes clear that the life concept is failing. In fact, much that originates from human bodies does not fall under current biological or cultural classifications.How we construct the human biological self has consequences for understanding our health, how we reproduce, and what we are. These social constructions greatly influence our views on abortion, stem-cell research, human cloning, and our post-human future. A more accurate construction of the human biological self will help us better navigate these contentious issues. (shrink)

Marquis’ future-like-ours argument against the morality of abortion assumes animalism—a family of theories according to which we are animals. Such an assumption is theoretically useful for various reasons, e.g., because it provides the theoretical underpinning for a reply to the contraception-abstinence objection. However, the connection between the future-like-ours argument and one popular version of animalism can prove lethal to the former, or so I argue in this paper.

Is the mammalian embryo/fetus a part of the organism that gestates it? According to the containment view, the fetus is not a part of, but merely contained within or surrounded by, the gestating organism. According to the parthood view, the fetus is a part of the gestating organism. This paper proceeds in two stages. First, I argue that the containment view is the received view; that it is generally assumed without good reason; and that it needs substantial support if it (...) is to be taken seriously. Second, I argue that the parthood view derives considerable support from a range of biological and physiological considerations. I tentatively conclude in favour of the parthood view, and end by identifying some of the interesting questions it raises. (shrink)

We address three fundamental questions: What does it mean for an entity to be living? What is the role of inter-organismic collaboration in evolution? What is a biological individual? Our central argument is that life arises when lineage-forming entities collaborate in metabolism. By conceiving of metabolism as a collaborative process performed by functional wholes, which are associations of a variety of lineage-forming entities, we avoid the standard tension between reproduction and metabolism in discussions of life – a tension particularly evident (...) in discussions of whether viruses are alive. Our perspective assumes no sharp distinction between life and non-life, and does not equate life exclusively with cellular or organismal status. We reach this conclusion through an analysis of the capabilities of a spectrum of biological entities, in which we include the pivotal case of viruses as well as prions, plasmids, organelles, intracellular and extracellular symbionts, unicellular and multicellular life-forms. The usual criterion for classifying many of the entities of our continuum as non-living is autonomy. This emphasis on autonomy is problematic, however, because even paradigmatic biological individuals, such as large animals, are dependent on symbiotic associations with many other organisms. These composite individuals constitute the metabolic wholes on which selection acts. Finally, our account treats cooperation and competition not as polar opposites but as points on a continuum of collaboration. We suggest that competitive relations are a transitional state, with multi-lineage metabolic wholes eventually outcompeting selfish competitors, and that this process sometimes leads to the emergence of new types or levels of wholes. Our view of life as a continuum of variably structured collaborative systems leaves open the possibility that a variety of forms of organized matter – from chemical systems to ecosystems – might be usefully understood as living entities. (shrink)

This paper addresses the question of what organisms are and therefore what kinds of biological entities qualify as organisms. For some time now, the concept of organismality has been eclipsed by the notion of individuality. Biological individuals are those systems that are units of selection. I develop a conception of organismality that does not rely on evolutionary considerations, but instead draws on development and ecology. On this account, organismality and individuality can come apart. Organisms, in my view, are as Godfrey-Smith (...) puts it “essentially persisters.” I argue that persistence is underpinned by differentiation, integration, development, and the constitutive embeddedness of organisms in their worlds. I examine two marginal cases, the Portuguese Man O’ War and the honey bee colony, and show that both count as organisms in light of my analysis. Next, I examine the case of holobionts, hosts plus their microsymbionts, and argue that they can be counted as organisms even though they may not be biological individuals. Finally, I consider the question of whether other, less tightly integrated biological systems might also be treated as organisms. (shrink)

Individuality is an important concept in biology, yet there are many non-equivalent criteria of individuality expressed in different kinds of biological individuals. This article evaluates these different kinds in terms of their capacity to support explanatory generalizations over the systems they individuate. Viewing the problem of individuality from this perspective promotes a splitting strategy in which different kinds make different epistemic trade-offs that suit them for different explanatory roles. I argue that evolutionary individuals, interpreted as forming a functional kind, face (...) difficulties of individuation and explanatory power that are mitigated by relying on more structurally based properties and non-evolutionary kinds. 1Introduction2Kinds of Biological Individuals3Evolutionary Individuals and Functional Kinds4Evolutionary versus Non-evolutionary Kinds of Individuals 4.1Physiological individuality4.2Ecological individuality4.3Developmental individuality5Conclusion. (shrink)

Darwin’s classic ‘Origin of Species’ (Darwin 1859) described forces of selection acting upon individuals, but there remains a great deal of controversy about what exactly the status and definition of a biological individual is. Recently some authors have argued that the individual is dispensable – that an inability to pin it down is not problematic because little rests on it anyway. The aim of this paper is to show that there is a real problem of biological individuality, and an urgent (...) need to arbitrate over the current plethora of solutions to it. (shrink)

Andrew Bourke’s Principles of Social Evolution identifies three stages that characterize an evolutionary transition in individuality and deploys inclusive fitness theory to explain each stage. The third stage, social group transformation, has hitherto received relatively little attention from inclusive fitness theorists. In this review, I first discuss Bourke’s “virtual dominance” hypothesis for the evolution of the germ line. I then contrast Bourke’s inclusive fitness approach to the major transitions with the multi-level approach developed by Richard Michod, Samir Okasha and others. (...) I suggest that, rather than choosing between these approaches, we should exploit the strengths of both. Finally, I stress the need for a firmer conceptual grasp of the nature of social group transformation. (shrink)

A number of claims are closely connected with, though logically distinct from, animalism. One is that organisms cease to exist when they die. Two others concern the relation of the brain, or the brainstem, to animal life. One of these holds that the brainstem is necessary for life—more precisely, that (say) my cat's brainstem is necessary for my cat's life to continue. The other is that it is sufficient for life—more precisely, that so long as (say) my cat's brainstem continues (...) to function, so too does my cat. I argue against these claims. (shrink)

In this paper we explore the organizational conditions underlying the emergence of organisms at the multicellular level. More specifically, we shall propose a general theoretical scheme according to which a multicellular organism is an ensemble of cells that effectively regulates its own development through collective mechanisms of control of cell differentiation and cell division processes. This theoretical result derives from the detailed study of the ontogenetic development of three multicellular systems and, in particular, of their corresponding cell-to-cell signaling networks. The (...) case study supports our claim that a specific type of functional integration among the cells of a multicellular ensemble , is required for it to qualify as a proper organism. Finally, we argue why a multicellular system exhibiting this type of functionally differentiated and integrated developmental organization becomes a self-determining collective entity and, therefore, should be considered as a second-order autonomous system. (shrink)

The impressive variation amongst biological individuals generates many complexities in addressing the simple-sounding question what is a biological individual? A distinction between evolutionary and physiological individuals is useful in thinking about biological individuals, as is attention to the kinds of groups, such as superorganisms and species, that have sometimes been thought of as biological individuals. More fully understanding the conceptual space that biological individuals occupy also involves considering a range of other concepts, such as life, reproduction, and agency. There has (...) been a focus in some recent discussions by both philosophers and biologists on how evolutionary individuals are created and regulated, as well as continuing work on the evolution of individuality. (shrink)