Do animals have culture?

Culture is probably not rare in animals, although hard experimental evidence is lacking. The strongest case for culture is found in the species most amenable to experimental manipulation, rather than in nonhuman primates. Human culture is much more likely to be cumulative than animal culture, but the reasons for this are not well established. At this point, there is no reason to assume that cumulative culture depends critically on teaching, imitation, language, or perspective‐taking. Currently, animals are being judged according to stricter criteria than humans.     

Bridging the explanatory gaps: What can we learn from a biological agency perspective?

We begin this article by delineating the explanatory gaps left by prevailing gene-focused approaches in our understanding of phenotype determination, inheritance, and the origin of novel traits. We aim not to diminish the value of these approaches but to highlight where their implementation, despite best efforts, has encountered persistent limitations. We then discuss how each of these explanatory gaps can be addressed by expanding research foci to take into account biological agency—the capacity of living systems at various levels to participate in their own development, maintenance, and function by regulating their structures and activities in response to conditions they encounter. Here we aim to define formally what agency and agents are and—just as importantly—what they are not, emphasizing that agency is an empirical property connoting neither intention nor consciousness. Lastly, we discuss how incorporating agency helps to bridge explanatory gaps left by conventional approaches, highlight scientific fields in which implicit agency approaches are already proving valuable, and assess the opportunities and challenges of more systematically incorporating biological agency into research programs.     

Spontaneous discrimination of possible and impossible objects by newly hatched chicks

Four-month-old infants can integrate local cues provided by two-dimensional pictures and interpret global inconsistencies in structural information to discriminate between possible and impossible objects. This leaves unanswered the issue of the relative contribution of maturation of biologically predisposed mechanisms and of experience with real objects, to the development of this capability. Here we show that, after exposure to objects in which junctions providing cues to global structure were occluded, day-old chicks selectively approach the two-dimensional image that depicted the possible rather than the impossible version of a three-dimensional object, after restoration of the junctions. Even more impressively, completely naive newly hatched chicks showed spontaneous preferences towards approaching two-dimensional depictions of structurally possible rather than impossible objects. These findings suggest that the vertebrate brain can be biologically predisposed towards approaching a two-dimensional image representing a view of a structurally possible three-dimensional object.     

From mechanisms to function: an integrated framework of animal innovation

Animal innovations range from the discovery of novel food types to the invention of completely novel behaviours. Innovations can give access to new opportunities, and thus enable innovating agents to invade and create novel niches. This in turn can pave the way for morphological adaptation and adaptive radiation. The mechanisms that make innovations possible are probably as diverse as the innovations themselves. So too are their evolutionary consequences. Perhaps because of this diversity, we lack a unifying framework that links mechanism to function. We propose a framework for animal innovation that describes the interactions between mechanism, fitness benefit and evolutionary significance, and which suggests an expanded range of experimental approaches. In doing so, we split innovation into factors (components and phases) that can be manipulated systematically, and which can be investigated both experimentally and with correlational studies. We apply this framework to a selection of cases, showing how it helps us ask more precise questions and design more revealing experiments.     

基于生态位构建的n-种群集合种群动态分析

生态位构建是指任何有机体具有的对环境的修复作用,其可能对集合种群的动态与分布产生深刻的影响.尝试性的将生态位构建概念引入集合种群的续存与动态这一复杂问题的研究中,建立了具有生态位构建作用的多物种集合种群的数学模型.模拟结果表明:随着生态位构建能力的增强,种群的续存能力和平衡态大小都有所增加;在此过程中,生态序的变化具有一定的规律性,分别呈现灭绝数为零的 1、 3、 5、 7和 9的协同演化.     

From hominins to humans: how sapiens became behaviourally modern

This paper contributes to a debate in the palaeoarchaeological community about the major time-lag between the origin of anatomically modern humans and the appearance of typically human cultural behaviour. Why did humans take so long—at least 100 000 years—to become ‘behaviourally modern’? The transition is often explained as a change in the intrinsic cognitive competence of modern humans: often in terms of a new capacity for symbolic thought, or the final perfection of language. These cognitive breakthrough models are not satisfactory, for they fail to explain the uneven palaeoanthropological record of human competence. Many supposed signature capacities appear (and then disappear) before the supposed cognitive breakthrough; many of the signature capacities disappear again after the breakthrough. So, instead of seeing behavioural modernity as a simple reflection of a new kind of mind, this paper presents a niche construction conceptual model of behavioural modernity. Humans became behaviourally modern when they could reliably transmit accumulated informational capital to the next generation, and transmit it with sufficient precision for innovations to be preserved and accumulated. In turn, the reliable accumulation of culture depends on the construction of learning environments, not just intrinsic cognitive machinery. I argue that the model is (i) evolutionarily plausible: the elements of the model can be assembled incrementally, without implausible selective scenarios; (ii) the model coheres with the broad palaeoarchaeological record; (iii) the model is anthropologically and ethnographically plausible; and (iv) the model is testable, though only in coarse, preliminary ways.     

Are forest‐shrubland mosaics of the Cape Floristic Region an example of alternate stable states?

The idea of alternate stable states (ASS) has been used to explain the juxtaposition of distinct vegetation types within the same climate regime. ASS may explain the co‐existence of relatively inflammable closed‐canopy Afrotemperate forest patches (‘Forest’) within fire‐prone open‐canopy Fynbos in the Cape Floristic Region (CFR) on sandstone‐derived soils. We evaluated the hypothesis that although fire and local topography and hydrology likely determined the paleogeographic boundaries of Forest, present‐day boundaries are additionally imposed by emergent edaphic properties and disturbance histories. We studied vegetation and edaphic properties of Forest‐Transition‐Fynbos vegetation at two sites within the CFR on sandstone‐derived soils and tracked historical change using aerial photography. Whereas Forest and Fynbos have changed little in extent or density since 1945, transition vegetation increased into areas formerly occupied by Fynbos. Forest soils were ubiquitously more nutrient‐rich than Fynbos soils, with transition soils being intermediate. These edaphic differences are not due to geological differences, but instead appear to have emerged as a consequence of different nutrient cycling within the different ecosystems. Soil nutrients are now so different that a switch from Fynbos to Forest is unlikely, in the short term (i.e. decades). Floristically and nutritionally, transitional vegetation is more similar to Fynbos than Forest and may be less resilient to changes in exogenous drivers (e.g. fire). Our findings are consistent with the idea that geologically Forest and Fynbos are largely fire‐derived long‐term ASS, with the stability of each state reinforced by marked soil nutrient differences. In contrast, the intermediate transitional vegetation that might switch states is unlikely to be stable.     

Natural mortality of puffadder shysharks due to Cape fur seals and black‐backed kelp gulls at Seal Island, South Africa

Natural mortality of puffadder shysharks Haploblepharus edwardsii due to two species of marine tetrapod, the Cape fur seal Arctocephalus pusillus pusillus and the black‐backed kelp gull Larus dominicanis vetula , is reported. These data constitute the first multiple observations of natural mortality of any cartilaginous fish due to object play or kleptoparasitism by marine tetrapods. Evidence of range extension of the puffadder shyshark to False Bay, South Africa is presented.