31 research outputs found
Pro-sociality without empathy
Empathy, the capacity to recognize and share feelings experienced by another individual, is an important trait in humans, but is not the same as pro-sociality, the tendency to behave so as to benefit another individual. Given the importance of understanding empathy's evolutionary emergence, it is unsurprising that many studies attempt to find evidence for it in other species. To address the question of what should constitute evidence for empathy, we offer a critical comparison of two recent studies of rescuing behaviour that report similar phenomena but are interpreted very differently by their authors. In one of the studies, rescue behaviour in rats was interpreted as providing evidence for empathy, whereas in the other, rescue behaviour in ants was interpreted without reference to sharing of emotions. Evidence for empathy requires showing that actor individuals possess a representation of the receiver's emotional state and are driven by the psychological goal of improving its wellbeing. Proving psychological goal-directedness by current standards involves goal-devaluation and causal sensitivity protocols, which, in our view, have not been implemented in available publications. Empathy has profound significance not only for cognitive and behavioural sciences but also for philosophy and ethics and, in our view, remains unproven outside humans.M.V. was funded by a Post-doctoral Fellowship (SFRH/BPD/79311/2011) awarded by the Portuguese Foundationfor Science and Technolog
Jack of All Trades, Master of All: A Positive Association between Habitat Niche Breadth and Foraging Performance in Pit-Building Antlion Larvae
Species utilizing a wide range of resources are intuitively expected to be less efficient in exploiting each resource type compared to species which have developed an optimal phenotype for utilizing only one or a few resources. We report here the results of an empirical study whose aim was to test for a negative association between habitat niche breadth and foraging performance. As a model system to address this question, we used two highly abundant species of pit-building antlions varying in their habitat niche breadth: the habitat generalist Myrmeleon hyalinus, which inhabits a variety of soil types but occurs mainly in sandy soils, and the habitat specialist Cueta lineosa, which is restricted to light soils such as loess. Both species were able to discriminate between the two soils, with each showing a distinct and higher preference to the soil type providing higher prey capture success and characterizing its primary habitat-of-origin. As expected, only small differences in the foraging performances of the habitat generalist were evident between the two soils, while the performance of the habitat specialist was markedly reduced in the alternative sandy soil. Remarkably, in both soil types, the habitat generalist constructed pits and responded to prey faster than the habitat specialist, at least under the temperature range of this study. Furthermore, prey capture success of the habitat generalist was higher than that of the habitat specialist irrespective of the soil type or prey ant species encountered, implying a positive association between habitat niche-breadth and foraging performance. Alternatively, C. lineosa specialization to light soils does not necessarily confer upon its superiority in utilizing such habitats. We thus suggest that habitat specialization in C. lineosa is either an evolutionary dead-end, or, more likely, that this species' superiority in light soils can only be evident when considering additional niche axes
Chemical Defense by the Native Winter Ant (Prenolepis imparis) against the Invasive Argentine Ant (Linepithema humile)
The invasive Argentine ant (Linepithema humile) is established worldwide and displaces native ant species. In northern California, however, the native winter ant (Prenolepis imparis) persists in invaded areas. We found that in aggressive interactions between the two species, P. imparis employs a potent defensive secretion. Field observations were conducted at P. imparis nest sites both in the presence and absence of L. humile. These observations suggested and laboratory assays confirmed that P. imparis workers are more likely to secrete when outnumbered by L. humile. Workers of P. imparis were also more likely to secrete near their nest entrances than when foraging on trees. One-on-one laboratory trials showed that the P. imparis secretion is highly lethal to L. humile, causing 79% mortality. The nonpolar fraction of the secretion was chemically analyzed with gas chromatography/mass spectrometry, and found to be composed of long-chain and cyclic hydrocarbons. Chemical analysis of dissected P. imparis workers showed that the nonpolar fraction is derived from the Dufour's gland. Based on these conclusions, we hypothesize that this chemical defense may help P. imparis to resist displacement by L. humile
Specialized Learning in Antlions (Neuroptera: Myrmeleontidae), Pit-Digging Predators, Shortens Vulnerable Larval Stage
Unique in the insect world for their extremely sedentary predatory behavior, pit-dwelling larval antlions dig pits, and then sit at the bottom and wait, sometimes for months, for prey to fall inside. This sedentary predation strategy, combined with their seemingly innate ability to detect approaching prey, make antlions unlikely candidates for learning. That is, although scientists have demonstrated that many species of insects possess the capacity to learn, each of these species, which together represent multiple families from every major insect order, utilizes this ability as a means of navigating the environment, using learned cues to guide an active search for food and hosts, or to avoid noxious events. Nonetheless, we demonstrate not only that sedentary antlions can learn, but also, more importantly, that learning provides an important fitness benefit, namely decreasing the time to pupate, a benefit not yet demonstrated in any other species. Compared to a control group in which an environmental cue was presented randomly vis-à-vis daily prey arrival, antlions given the opportunity to associate the cue with prey were able to make more efficient use of prey and pupate significantly sooner, thus shortening their long, highly vulnerable larval stage. Whereas “median survival time,” the point at which half of the animals in each group had pupated, was 46 days for antlions receiving the Learning treatment, that point never was reached in antlions receiving the Random treatment, even by the end of the experiment on Day 70. In addition, we demonstrate a novel manifestation of antlions' learned response to cues predicting prey arrival, behavior that does not match the typical “learning curve” but which is well-adapted to their sedentary predation strategy. Finally, we suggest that what has long appeared to be instinctive predatory behavior is likely to be highly modified and shaped by learning
Pharmacopées et pharmacie au Moyen-Orient
Arzneibücher und pharmazie im Mittlerenorient
Die Autoren haben eine Untersuchung durchgeführt, um die Arzneibücher genau kennenzulernen, die in 150 Ländern der heutigen ökonomischen Welt - trotz der politischen Fluktuationen - gebraucht Werden.
Der vorliegende Vortrag enthält einen besonderen Auszug dieser Arbeit. Es ist in der Tat interessant, die verschiedenen Tendenzen im Bereich der pharmazeutischen Gesetzgebung in Ländern mit sehr veränderlichem okonomischen und politischen Zusammenfluss, wie im Mittlerenorient, kennenzulernen.
Wir werden dort, parallel zu den Ländern, die einen abendländischen Gebrauch der Arzneibücher handhaben, wie das nationale französische Arzneibuch in Syrien und das britische in Kuweit, Länder finden, die ein eigenes nationales Arzneibuch besitzen, wie : die Türkei, der Irak, und die Vereinigte Arabische Republik (agyptisches Arzneibuch), oder die sich um die Akzeptierung eines universeilen Arzneibuch bemühen, wie das Internationale Arzneibuch.
Endlich bereiten bestimmte Staaten einen Codex oder ein Formelbuch unter der Schirmherrschaft des "Conseil de l'Ordre" oder des Gesundheitsministeriums vor.Pharmacopoeias and Pharmacy in Middle-East
An investigation was conducted by the authors to know with precision, despite of political changes, the pharmacopoeia or pharmacopoeias in use in the 150 countries of the world.
The present communication is drawn from a piece of work carried out since 4 years on this problem. It is of a great interest to know the different tendencies of the pharmaceutical legislation in some countries situated at an economic and political crossroads of the Middle-East.
In this group, we shall find some countries who keep up the tradition of western pharmacopoeia, such as the National French one in Syris or the British one in Koweit. Other countries are attached to their National Pharmacopoeias, such as Turkey, Irak or the U.A.R. (Egyptian Pharmacopoeia), or have committed themselves to accept an universal system like the International Pharmacopoeia.
Finally, a number of States are working on a Codex or Formulary which will be executed under the sponsorship of the Council of the Order or of the Ministry of Health.Nowbahari A., de Roeck-Holtzhauer Yannick. Pharmacopées et pharmacie au Moyen-Orient. In: Revue d'histoire de la pharmacie, 63ᵉ année, n°226, 1975. Communications du congrès international d'histoire de la pharmacie de Paris (24-29 septembre 1973) pp. 491-499