A view from the bridge: Subjectivity,embodiment and animal minds

Abstract

In contemporary discussions of animal mind the difficulty of studying the nature of private, subjective awareness in animals is often seen as a barrier to a fuller understanding of animal experience. Relatively little work has focused on more recent psychological accounts of mind that emphasize its extended, embodied and social aspects. We examine some of the main conceptual difficulties in this area, and then consider a number of more embodied approaches. We suggest that a consideration of the nature of the animal-human relationship is crucial to a consideration of animal awareness.     

Mechanisms of cryoprotection in freezing tolerant animal systems

The theoretical mechanisms of freezing protection afforded by the natural occurrence of glycerol in an adult, freezing-tolerant insect have been considered in light of recent findings. While unequivocal identification of the specific site or sites of action of glycerol is yet obscured in a maze of interactions, it is apparent that a multicellular system (organism) that naturally possesses glycerol in high, nonlethal concentrations, that can maintain activity in the presence of tissue ice, that can survive frequent and prolonged freeze-thaw encounters, and finally, that can regulate cryoprotectant levels in the presence of changing environmental conditions should be a major focus of future studies.The carabid beetle, Pterostichus brevicornis has been found to regulate glycerol levels in response to fluctuating ambient temperatures even while frozen. Hemolymph freezing points and whole-body supercooling points correlated well with changes in glycerol. Freezing and supercooling points decreased 0.9 ° C per 4 g/100 ml increase in glycerol.An interpretation of the data accumulated on insect studies and integrated with data from other multicellular systems supports the theory that a single site of freezing concept as applied to considerations of cryoprotection and cryoinjury may not be realistic. Each level of events occurring during the freezing process in glycerolated and nonglycerolated animal systems has been discussed. There appears little room for speculative separation and isolation of the site of action for the events of freezing (and thawing) represent a continuum with changes in each parameter directly dependent upon the entire sequence.     

A systems approach to animal communication

Why animal communication displays are so complex and how they have evolved are active foci of research with a long and rich history. Progress towards an evolutionary analysis of signal complexity, however, has been constrained by a lack of hypotheses to explain similarities and/or differences in signalling systems across taxa. To address this, we advocate incorporating a systems approach into studies of animal communication—an approach that includes comprehensive experimental designs and data collection in combination with the implementation of systems concepts and tools. A systems approach evaluates overall display architecture, including how components interact to alter function, and how function varies in different states of the system. We provide a brief overview of the current state of the field, including a focus on select studies that highlight the dynamic nature of animal signalling. We then introduce core concepts from systems biology (redundancy, degeneracy, pluripotentiality, and modularity) and discuss their relationships with system properties (e.g. robustness, flexibility, evolvability). We translate systems concepts into an animal communication framework and accentuate their utility through a case study. Finally, we demonstrate how consideration of the system-level organization of animal communication poses new practical research questions that will aid our understanding of how and why animal displays are so complex.     

Particulate delivery systems for animal vaccines

The requirements for veterinary vaccines are different to those of human vaccines. Indeed, while more side effects can be tolerated in animals than in humans; there are stricter requirements in terms of cost, ease of delivery (including to wildlife), and a need to develop vaccines in species for which relatively little is known in terms of molecular immunology. By their nature particulate vaccine delivery systems are well suited to address these challenges. Here, we review particulate vaccine delivery systems, ranging from cm-sized long-distance ballistic devices to nano-bead technology for veterinary species and wildlife.     

Transfection systems for animal models of malaria

Transfection of malaria parasites is a rapidly emerging technology that offers great promise for the investigation of many aspects of infection. Animal models of malaria have always played an important role in the investigation of the disease. In this article, two of the Dutch groups that have been involved in combining transfection with animal models describe the relevant techniques and recent vector developments for the expression of transgenes, giving examples of their application.     

An evaluation of intra-cage ventilation in three animal caging systems

Although temperature and relative humidity have been quantitated and their effects on research data studied, few studies have measured the air turnover rates at cage level. We evaluated the air distribution and air turnover rates in unoccupied shoe-box mouse cages, filter-top covered cages and shoe-box mouse cages housed in a flexible film isolator by using discontinuous gas chromatography/mass spectrometry and smoke. Results showed that air turnover was most rapid in the unoccupied shoe-box mouse cage and slowest in the filter-top covered cage. Placing mice in the filter-top covered cage did not significantly improve the air turnover rate. Although filter-top covered cages reduce cage-to-cage transmission of disease, the poor airflow observed within these cages could lead to a buildup of gaseous pollutants that may adversely affect the animal's health.     

Splicing of plant pre-mRNAs in animal systems and vice versa

To investigate similarities and differences of pre-mRNA splicing between higher plants and animals, we tested whether pre-mRNAs of higher plants can be accurately spliced in animal systems, and whether an animal pre-mRNA can be spliced in plant cells. Pre-mRNAs of the maize bronze locus and oat phytochrome type 3 are accurately spliced with moderate efficiency in a human (HeLa cell) nuclear extract. The first intervening sequence (IVS1) of bean phaseolin pre-mRNA is not excised in the human nuclear extract, but is removed (although at low efficiency) in intact monkey cells. However, the IVS1 of human alpha-globin pre-mRNA is not removed in tobacco cells. Our data suggest that the mechanisms of pre-mRNA splicing are similar, but not identical, in plants and animals.