Grant Ramsey

The developmental properties of organisms play important roles in the generation of variation necessary for evolutionary change. But how can individual development steer the course of evolution? To answer this question, we introduce developmental channeling as a disposition of individual organisms that shapes their possible developmental trajectories and evolutionary dappling as an evolutionary outcome in which the space of possible organismic forms is dappled—it is only partially filled. We then trace out the implications of the channeling-dappling framework for contemporary debates in the philosophy of evolution, including evolvability, reciprocal causation, and the extended evolutionary synthesis.

The validity and utility of the proximate-ultimate distinction in biology have recently been under debate. Opponents of the distinction argue that it rules out individual-level organismic processes from evolutionary explanations, thereby leading to an unfounded separation between organismic causation and evolutionary causation. Proponents of the proximate-ultimate distinction, on the other hand, argue that it serves an important epistemological role in forming different kinds of explanation-seeking questions in biology. In this paper we offer an interpretation the proximate-ultimate distinction not only as a means of forming explanation-seeking questions, but also as a distinction that can help highlight the way in which individual-level organismic processes can be evolutionary causes. We do this by interpreting the distinction between proximate and ultimate causes as a distinction between structuring and triggering causes.

In this paper, we distinguish two different approaches to cultural evolution. One approach is meme-centered, the other organism-centered. We argue that in situations in which the meme- and organism-centered approaches are competing alternatives, the organism-centered approach is in many ways superior. Furthermore, the organism-centered approach can go a long way toward understanding the evolution of institutions. Although the organism-centered approach is preferable for a broad class of situations, we do leave room for super-organismic or sub-organismic explanations of some cultural phenomena.

Culture in humans connotes tradition, norms, ritual, technology, and social learning, but also cultural events like operas or gallery openings. Culture is in part about what we do, but also sometimes about what we ought to do. Human culture is inextricably intertwined with language and much of what we learn and transmit to others comes through written or spoken language. Given the complexities of human culture, it might seem that we are the only species that exhibits culture. How, then, are we to make sense of culture in animals? The study of animal culture is a booming research area. Culture is said to occur in a wide range of vertebrates from our close kin, chimpanzees and orangutans, to more distant relatives like rats and whales. Could these studies be misleading in that they are not actually studying culture but simply misapplying the term ‘culture’? Or is what is labeled culture in animals at the core of human culture, so that although human culture is more elaborate than animal culture, it is different in degree, not kind? While it is certainly easy to intentionally define culture in a way that makes it unique to humans, because of the growing field of animal culture, it would be most useful to attempt to offer a definition of culture that makes sense of how it is used by psychologists, biologists, anthropologists, and others who use the term culture in studies of animal behavior. The challenge is to produce a concept that is broad enough to be able to apply across humans and animals, but not be so anemic that it cannot do justice to human culture. Because of this, I will here construct a definition of animal culture and draw out some of its implications.

Conceptions of human nature fall under two broad categories, trait bin accounts and trait cluster accounts. Trait bin accounts take there to be a special bin of traits, one composed of all and only those traits constituting our nature. For those arguing for a trait bin account of human nature, the challenge is to articulate what it is that marks a trait as being in or outside of the bin. For some, the bin is filled by the traits essential to being human. Others, such as Machery in his contribution to this volume, offer a non-essentialist trait bin conception of human nature. In this chapter, I argue that trait bin approaches to human nature are misguided, that there is no good way of dividing human traits into those that are a part of our nature and those that are not. Instead, I argue for a trait cluster account, which sees human nature not as a special bin of traits, but as the relationship among traits. Under this account, human nature lies in the patterns of trait expression within and across human life histories. This account does a superior job characterizing what humans are like and aligning human nature with the human sciences.

There is clearly a plurality of forms of altruism. Classically, biological altruism is distinguished from psychological altruism. Recent discussions of altruism have attempted to distinguish even more forms of altruism. I will focus on three altruism concepts, biological altruism, psychological altruism, and helping altruism. The questions I am concerned with here are, first, how should we understand these concepts? and second, what relationship do these concepts bear to one another? In particular, is there an essence to altruism that unifies these concepts? I suggest that while there is no essence to altruism, this does not mean that the array of altruism concepts is completely disunified. Instead, I propose we place all the concepts into a common framework-an altruism space-that could lead to new questions about how this space can be filled.

Population-level theories of evolution—the stock and trade of population genetics—are statistical theories par excellence. But what accounts for the statistical character of population-level phenomena? One view is that the population-level statistics are a product of, are generated by, probabilities that attach to the individuals in the population. On this conception, population-level phenomena are explained by individual-level probabilities and their population-level combinations. Another view, which arguably goes back to Fisher but has been defended recently, is that the population-level statistics are sui generis, that they somehow emerge from the underlying deterministic behavior of the individuals composing the population. Walsh et al. label this the statistical interpretation. We are not willing to give them that term, since everyone will admit that the population-level theories of evolution are statistical, so we will call this the emergentist statistical interpretation. Our goals are to show that: This interpretation is based on gross factual errors concerning the practice of evolutionary biology, concerning both what is done and what can be done; its adoption would entail giving up on most of the explanatory and predictive projects of evolutionary biology; and finally a rival interpretation, which we will label the propensity statistical interpretation succeeds exactly where the emergentist interpretation fails.

Adaptationism is often taken to be the thesis that most traits are adaptations. In order to assess this thesis, it seems we must be able to establish either an exhaustive set of all traits or a representative sample of this set. Either task requires a more systematic and principled way of individuating traits than is currently available. Moreover, different trait individuation criteria can make adaptationism turn out true or false. For instance, individuation based on natural selection may render adaptationism true, but may do so by presupposing adaptationism. In this paper, we show how adaptationism depends on trait individuation and that the latter is an open and unsolved problem.

A major debate in the philosophy of biology centers on the question of how we should understand the causal structure of natural selection. This debate is polarized into the causal and statistical positions. The main arguments from the statistical side are that a causal construal of the theory of natural selection's central concept, fitness, either (i) leads to inaccurate predictions about population dynamics, or (ii) leads to an incoherent set of causal commitments. In this essay, I argue that neither the predictive inaccuracy nor the incoherency arguments successfully undermine the causal account of fitness. 1 Introduction2 The Importance of Trait Fitness3 Trait Fitness is not a Silver Bullet4 The Fundamental Incoherency Argument5 Car Racing and Trait Fitness Reversals6 Population Subdivisions and Evolution7 The STP and the Argument for the Incoherency of the Causal Account of Fitness8 Conclusions.

Some unpleasant emotions, like fear and disgust, appear straightforwardly susceptible to evolutionary explanation on account of the benefits they seem to provide to individuals. But guilt is more puzzling in this respect. Like other unpleasant emotions, guilt is often associated with a host of negative effects on the individual, such as psychological suffering and social withdrawal. Moreover, many guilt-induced behaviors, such as revealing one’s offenses and placing oneself before the mercy of others, could levy a cost to individuals that is not outweighed by guilt’s benefits. Supposing there is an evolutionary story to tell about the origins of guilt, the question is how such negative effects were sufficiently outweighed by the potential fitness payoffs that guilt might have yielded to individuals. In this article, we consider which forms of evolution could have resulted in guilt, and whether current evidence can tell us which form of evolution most likely occurred.

Millions of scientific articles are published each year, making it difficult to stay abreast of advances within even the smallest subdisciplines. Traditional approaches to the study of science, such as the history and philosophy of science, involve closely reading a relatively small set of journal articles. And yet many questions benefit from casting a wider net: Is most scientific change gradual or revolutionary? What are the key sources of scientific novelty? Over the past several decades, a massive effort to digitize the academic literature and equip computers with algorithms that can distantly read and analyze a digital database has taken us one step closer to answering these questions. The Dynamics of Science brings together a diverse array of contributors to examine the largely unexplored computational frontiers of history and philosophy of science. Together, they reveal how tools and data from automated textual analysis, or machine "reading," combined with methods and models from game theory and cultural evolutionary theory, can begin to answer fundamental questions about the nature and history of science.

What does it mean for our species—or for any species—to be successful? Human Success: Evolutionary Origins and Ethical Implications examines the concept of human success from a variety of disciplinary perspectives, with contributions from leading paleobiologists, anthropologists, geologists, philosophers of science, and ethicists. It tells the tale of how the human species grew in success-linked metrics, such as population size and geographical range, and how it came to dominate ecological systems across the globe. It explores how culture, technology, and creativity have contributed to human success. However, there is a darker side of human success, as has become apparent in a world affected by climate change and the destruction of biodiversity. This leads us to ask whether the human species can really be called successful, and what our future success will look like in terms of our bodies, minds, morals, and our place in the universe. The essays in this book probe us to reflect on what has led to our apparent evolutionary success—and, most important, what this success implies for the future of our species.

During the battle of Iwo Jima in June 1944, Private First Class Jackylin Harold Lucas and three other U.S. Marines came under attack while making their way along a ravine. Upon seeing two grenades thrown near the soldiers, Lucas dove onto one grenade and pulled the other under his body, saving his companions from serious injury or death. Lucas survived, but his injuries were so grave that his companions left him for dead. Lucas’s act was one of spectacular and nearly suicidal altruism. What does such an act show us about our nature and the human capacity for good and evil? Perhaps it offers a window onto our true nature—a nature ultimately good, though susceptible to corrupting influences. Or perhaps it seems extraordinary precisely because we are greedy and violent by nature but can, in rare instances, rise above those instincts. Questions about what human nature is and how we can learn about it are difficult to answer. They are difficult not just because humans are complex creatures whose behavior is deeply embedded in the cultural environment that they are a part of, but also because it is not obvious what a concept of human nature is supposed to do or what it is for. The concept of human nature is often used as a normative concept, one that can serve as a guide to action, showing us how we ought to behave. Less commonplace is an approach that seeks a descriptive account of human nature, one that characterizes what humans do and are disposed to do. I argue in this essay that the normative and descriptive approaches are at odds and that we should not expect a single concept of human nature to play both roles. Furthermore, there are deep problems with normative accounts. They often ignore or contradict the contemporary scientific worldview, and they often merely reflect biases about how we ought to be and what we ought to do. Human nature in this sense becomes politicized and serves in arguments about the moral status of issues like homosexuality, abortion, or biomedical enhancement. Because of the problems inherent in normative notions of human nature, I offer a descriptive alternative. My alternative attempts to align the scientific study of the human with human nature.

In this paper, we distinguish two different approaches to cultural evolution. One approach is meme-centered, the other organism-centered. We argue that in situations in which the meme- and organism-centered approaches are competing alternatives, the organism-centered approach is in many ways superior. Furthermore, the organism-centered approach can go a long way toward understanding the evolution of institutions. Although the organism-centered approach is preferable for a broad class of situations, we do leave room for super-organismic (group based) or sub-organismic (meme-based) explanations of some cultural phenomena.

Culture in humans connotes tradition, norms, ritual, technology, and social learning, but also cultural events like operas or gallery openings. Culture is in part about what we do, but also sometimes about what we ought to do. Human culture is inextricably intertwined with language and much of what we learn and transmit to others comes through written or spoken language. Given the complexities of human culture, it might seem that we are the only species that exhibits culture. How, then, are we to make sense of culture in animals? The study of animal culture is a booming research area. Culture is said to occur in a wide range of vertebrates from our close kin, chimpanzees and orangutans, to more distant relatives like rats and whales. Could these studies be misleading in that they are not actually studying culture but simply misapplying the term ‘culture’? Or is what is labeled culture in animals at the core of human culture, so that although human culture is more elaborate than animal culture, it is different in degree, not kind? While it is certainly easy to intentionally define culture in a way that makes it unique to humans, because of the growing field of animal culture, it would be most useful to attempt to offer a definition of culture that makes sense of how it is used by psychologists, biologists, anthropologists, and others who use the term culture in studies of animal behavior. The challenge is to produce a concept that is broad enough to be able to apply across humans and animals, but not be so anemic that it cannot do justice to human culture. Because of this, I will here construct a definition of animal culture and draw out some of its implications.

The dynamics of epiphytic bryophyte communities following natural and human disturbance have rarely been quantified. We describe the response of bryophyte communities on bigleaf maple trees in Olympia, Washington, following their experimental removal. Approximately 8% of the exposed area was recolonized by bryophytes 1 year after clearing, and 27% after 3 years. Lateral encroachment from bryophytes on the sides of the 20-cm-long plots accounted for 75% of this recolonization, with growth from residual plant parts or aerially dispersed diaspores accounting for the remaining 25%. Though it was not possible to distinguish between the latter two sources of cover, the number of clear de novo colonization events over the course of the year was low. Disturbance appeared to reduce bryophyte diversity at this successional stage, as alpha and gamma diversity remained low after 1 year and had not recovered after 3 years. Reflecting the preponderance of lateral encroachment as the mechanism for recolonization, disturbance size may significantly affect the time needed to recolonize disturbed branch substrates. In addition to contributing to ecologists' understanding of processes of succession, these experiments may help to develop sustainable practices for moss-harvesting in the Pacific Northwest.Key words: succession, bryophytes, epiphytes, Acer macrophyllum, recolonization, canopy studies.

Programmed cell death (PCD) in unicellular organisms is in some instances an altruistic trait. When the beneficiaries are clones or close kin, kin selection theory may be used to explain the evolution of the trait, and when the trait evolves in groups of distantly related individuals, group or multilevel selection theory is invoked. In mixed microbial communities, the benefits are also available to unrelated taxa. But the evolutionary ecology of PCD in communities is poorly understood. Few hypotheses have been offered concerning the community role of PCD despite its far-reaching effects. The hypothesis we consider here is that PCD is a black queen. The Black Queen Hypothesis (BQH) outlines how public goods arising from a leaky function are exploited by other taxa in the community. Black Queen (BQ) traits are essential for community survival, but only some members bear the cost of possessing them, while others lose the trait In addition, BQ traits have been defined in terms of adaptive gene loss, and it is unknown whether this has occurred for PCD. Our conclusion is that PCD fulfils the two most important criteria of a BQ (leakiness and costliness), but that more empirical data are needed for assessing the remaining two criteria. In addition, we hold that for viewing PCD as a BQ, the original BQH needs to include social traits. Thus, despite some empirical and conceptual shortcomings, the BQH provides a helpful avenue for investigating PCD in microbial communities.