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Laurent Prtt Jennifer Mickelberg Jodi Carrigan Tara Stoinski Redouan Bshary Sarah F. Brosnan 《American journal of primatology》2021,83(1)
A goal of the comparative approach is to test a variety of species on the same task. Here, we examined whether the factors that helped capuchin monkeys improve their performance in a dichotomous choice task would generalize to three other primate species: orangutans, gorillas, and drill monkeys. In this task, subjects have access to two options, each resulting in an identical food, but one (the ephemeral option) is only available if it is chosen first, whereas the other one (the permanent option) is always available. Therefore, the food‐maximizing solution is to choose the ephemeral option first, followed by the permanent option for an additional reward. On the original version (plate task), the options were discriminated by the color and pattern of the plates holding the food, while on two subsequent versions we used altered cues that we predicted would improve performance: (1) the color of the foods themselves (color task), which we hypothesized was relevant to primates, who choose foods rather than substrates on which foods are found when foraging, and (2) patterned cups covering the foods (cup task), which we hypothesized would help primates avoid the prepotent response associated with visible food. Like capuchins, all three species initially failed to solve the plate task. However, while orangutans improved their performance from the plate to the color task, they did not for the cup task, and only a few gorillas and no drills succeeded in either task. Unfortunately, our ability to interpret these data was obscured by differences in the subjects' level of experience with cognitive testing and practical constraints that precluded the use of completely identical procedures across species. Nonetheless, we consider what these results can tell us, and discuss the value of conducting studies across multiple sites despite unavoidable differences. 相似文献
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Sarah F. Brosnan Owen D. Jones Molly Gardner Susan P. Lambeth Steven J. Schapiro 《Evolution and human behavior》2012,33(4):378-386
Cognitive and behavioral biases, which are widespread among humans, have recently been demonstrated in other primates, suggesting a common origin. Here we examine whether the expression of one shared bias, the endowment effect, varies as a function of context. We tested whether objects lacking inherent value elicited a stronger endowment effect (or preference for keeping the object) in a context in which the objects had immediate instrumental value for obtaining valuable resources (food). Chimpanzee subjects had opportunities to trade tools when food was not present, visible but unobtainable, and obtainable using the tools. We found that the endowment effect for these tools existed only when they were immediately useful, showing that the effect varies as a function of context-specific utility. Such context-specific variation suggests that the variation seen in some human biases may trace predictably to behaviors that evolved to maximize gains in specific circumstances. 相似文献
316.
Jörg Barke Ryan F Seipke Sabine Grüschow Darren Heavens Nizar Drou Mervyn J Bibb Rebecca JM Goss Douglas W Yu Matthew I Hutchings 《BMC biology》2010,8(1):109
Background
Attine ants live in an intensely studied tripartite mutualism with the fungus Leucoagaricus gongylophorus, which provides food to the ants, and with antibiotic-producing actinomycete bacteria. One hypothesis suggests that bacteria from the genus Pseudonocardia are the sole, co-evolved mutualists of attine ants and are transmitted vertically by the queens. A recent study identified a Pseudonocardia-produced antifungal, named dentigerumycin, associated with the lower attine Apterostigma dentigerum consistent with the idea that co-evolved Pseudonocardia make novel antibiotics. An alternative possibility is that attine ants sample actinomycete bacteria from the soil, selecting and maintaining those species that make useful antibiotics. Consistent with this idea, a Streptomyces species associated with the higher attine Acromyrmex octospinosus was recently shown to produce the well-known antifungal candicidin. Candicidin production is widespread in environmental isolates of Streptomyces, so this could either be an environmental contaminant or evidence of recruitment of useful actinomycetes from the environment. It should be noted that the two possibilities for actinomycete acquisition are not necessarily mutually exclusive. 相似文献317.
The presence or absence of antibodies to citrullinated peptides/proteins (ACPA) is an important parameter that helps a clinician
set a diagnosis of early rheumatoid arthritis and, hence, initiate treatment. There are several commercial tests available
to measure ACPA levels, although it can be difficult to decide what the best test for a given clinical question is. We analyzed
literature data in which the diagnostic and other properties of various ACPA tests are compared. The results show that for
diagnostic purposes the CCP2 test has the highest specificity, the highest sensitivity in stratified studies and the highest
positive predictive value. For the prediction of future joint destruction the CCP2, MCV, and CCP3 tests may be used. The ability
to predict the likelihood of not achieving sustained disease-modifying antirheumatic drug-free remission was highest for the
CCP2 test. Finally, the levels of anti-CCP2 and anti-CCP3 (and possibly anti-mutated citrullinated vimentin) in rheumatoid
arthritis patients are not significantly influenced by TNFα blocking agents. 相似文献
318.
Ernst JM Helmreich 《Cell communication and signaling : CCS》2010,8(1):1-15
As one of the disciplines of systems biology, proteomics is central to enabling the elucidation of protein function within the cell; furthermore, the question of how to deduce protein structure and function from the genetic readout has gained new significance. This problem is of particular relevance for proteins engaged in cell signalling. In dealing with this question, I shall critically comment on the reliability and predictability of transmission and translation of the genetic blue print into the phenotype, the protein. Based on this information, I will then evaluate the intentions and goals of today's proteomics and gene-networking and appraise their chances of success. Some of the themes commented on in this publication are explored in greater detail with particular emphasis on the historical roots of concepts and techniques in my forthcoming book, published in German: Von Molekülen zu Zellen. 100 Jahre experimentelle Biologie. Betrachtungen eines Biochemikers. 相似文献
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Roel GW Verhaak Frank JT Staal Peter JM Valk Bob Lowenberg Marcel JT Reinders Dick de Ridder 《BMC bioinformatics》2006,7(1):105-15