1,962 research outputs found
Naïve Realism, Seeing Stars, and Perceiving the Past
It seems possible to see a star that no longer exists. Yet it also seems right to say that what no longer exists cannot be seen. We therefore face a puzzle, the traditional answer to which involves abandoning naïve realism in favour of a sense datum view. In this article, however, I offer a novel exploration of the puzzle within a naïve realist framework. As will emerge, the best option for naïve realists is to embrace an eternalist view of time, and claim that in the relevant case, one sees a still existent star‐stage located somewhere in the distant past
The process of genome shrinkage in the obligate symbiont Buchnera aphidicola
BACKGROUND: Very small genomes have evolved repeatedly in eubacterial lineages that have adopted obligate associations with eukaryotic hosts. Complete genome sequences have revealed that small genomes retain very different gene sets, raising the question of how final genome content is determined. To examine the process of genome reduction, the tiny genome of the endosymbiont Buchnera aphidicola was compared to the larger ancestral genome, reconstructed on the basis of the phylogenetic distribution of gene orthologs among fully sequenced relatives of Escherichia coli and Buchnera. RESULTS: The reconstructed ancestral genome contained 2,425 open reading frames (ORFs). The Buchnera genome, containing 564 ORFs, consists of 153 fragments of 1-34 genes that are syntenic with reconstructed ancestral regions. On the basis of this reconstruction, 503 genes were eliminated within syntenic fragments, and 1,403 genes were lost from the gaps between syntenic fragments, probably in connection with genome rearrangements. Lost regions are sometimes large, and often span functionally unrelated genes. In addition, individual genes and regulatory regions have been lost or eroded. For the categories of DNA repair genes and rRNA genes, most lost loci fall in regions between syntenic fragments. This history of gene loss is reflected in the sequences of intergenic spacers at positions where genes were once present. CONCLUSIONS: The most plausible interpretation of this reconstruction is that Buchnera lost many genes through the fixation of large deletions soon after the acquisition of an obligate endosymbiotic lifestyle. An implication is that final genome composition may be partly the chance outcome of initial deletions and that neighboring genes influence the likelihood of loss of particular genes and pathways
Grounding the Qualitative: A New Challenge for Panpsychism
This paper presents a novel challenge for the panpsychist solution to the problem of consciousness. It advances three main claims. First, that the problem of consciousness is really an instance of a more general problem: that of grounding the qualitative. Second, that we should want a general solution to this problem. Third, that panpsychism cannot provide it. I also suggest two further things: (1) that alternative kinds of Russellian monism may avoid the problem in ways panpsychists cannot, and (2) that a kind of neo-Aristotelian or ground-theoretical physicalism fares just as well here if not better
Living without microphysical supervenience
The Doctrine of Microphysical Supervenience states that microphysical duplicates cannot differ in their intrinsic properties. According to Merricks :59–71, 1998a, Objects and persons, Oxford University Press, 2001), however, this thesis is false, since microphysical duplicates can differ with respect to the intrinsic property of consciousness. In my view, Merricks’ argument is plausible, and extant attempts to reject it are problematic. However, the argument also threatens to make consciousness appear mysterious, by implying that consciousness facts fail to be microphysically determined and that there can be brute and inexplicable differences in consciousness between material things. The paper therefore develops an account that can respect the soundness of Merricks’ argument while avoiding these problematic consequences. At the heart of the proposal is the idea that consciousness can be microphysically grounded despite failing to microphysical supervene. The proposed view also has the interesting consequence that consciousness is an intrinsic property despite depending on extrinsic factors for its instantiation
Naïve Realism, Hallucination, and Causation: A New Response to the Screening Off Problem
This paper sets out a novel response to the ‘screening off’ problem for naïve realism. The aim is to resist the claim (which many naïve realists accept) that the kind of experience involved in hallucinating also occurs during perception, by arguing that there are causal constraints that must be met if an hallucinatory experience is to occur, ones that are never met in perceptual cases. Notably, given this response, it turns out that, contra current orthodoxy, naïve realists need not adopt any particular view about the psychological nature of hallucinatory experience to handle the screening off problem. Consequently, room opens up for naïve realists to endorse whatever theory of hallucinatory experience seems to best capture the distinctive nature of such episodes
Biological characteristics and mortality of western butterfish (Pentapodus vitta), an abundant bycatch species of prawn trawling and recreational fishing in a large subtropical embayment
The western butterfish (Pentapodus vitta) is numerous in the bycatch of prawn trawling and recreational fishing in Shark Bay, Western Australia. We have thus determined crucial aspects of its biological characteristics and the potential impact of fishing on its abundance within this large subtropical marine embayment. Although both sexes attained a maximum age of 8 years, males grow more rapidly and to a larger size. Maturity is attained at the end of the first year of life and spawning occurs between October and January. The use of a Bayesian approach to combine independent estimates for total mortality, Z, and natural mortality, M, yielded slightly higher point estimates for Z than M. This result indicates that P. vitta is lightly impacted by fishing. It is relevant that, potentially, the individuals can spawn twice before recruitment into the fishery and that 73% of recreationally caught individuals are returned live to the water
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