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Animal Cognition Sep 2023Learning by observing others (i.e. social learning) is an important mechanism to reduce the costs of individual learning. Social learning can occur between conspecifics...
Learning by observing others (i.e. social learning) is an important mechanism to reduce the costs of individual learning. Social learning can occur between conspecifics but also heterospecifics. Domestication processes might have changed the animals' sensitivity to human social cues and recent research indicates that domesticated species are particularly good in learning socially from humans. Llamas (Lama glama) are an interesting model species for that purpose. Llamas were bred as pack animals, which requires close contact and cooperative behaviour towards humans. We investigated whether llamas learn socially from trained conspecifics and humans in a spatial detour task. Subjects were required to detour metal hurdles arranged in a V-shape to reach a food reward. Llamas were more successful in solving the task after both a human and a conspecific demonstrated the task compared to a control condition with no demonstrator. Individual differences in behaviour (i.e. food motivation and distraction) further affected the success rate. Animals did not necessarily use the same route as the demonstrators, thus, indicating that they adopted a more general detour behaviour. These results suggest that llamas can extract information from conspecific and heterospecific demonstrations; hence, broadening our knowledge of domesticated species that are sensitive to human social behaviour.
Topics: Humans; Animals; Camelids, New World; Learning; Social Learning; Social Behavior; Cues
PubMed: 37410341
DOI: 10.1007/s10071-023-01808-8 -
Scientific Reports Dec 2023Resistance traits of honeybees (Apis mellifera) against their major parasite Varroa destructor have fascinated scientists and breeders for long. Nevertheless, the...
Resistance traits of honeybees (Apis mellifera) against their major parasite Varroa destructor have fascinated scientists and breeders for long. Nevertheless, the mechanisms underlying resistance are still largely unknown. The same applies to possible interactions between host behaviours, mite reproduction and seasonal differences. Two resistance traits, reproductive failure of mites and recapping of brood cells, are of particular interest. High rates of recapping at the colony level were found to correspond with low reproductive success of mites. However, the direct effect of recapping on mite reproduction is still controversial and both traits seem to be very variable in their expression. Thus, a deeper knowledge of both, the effect of recapping on mite reproduction and the seasonal differences in the expression of these traits is urgently needed. To shed light on this host-parasite interaction, we investigated recapping and mite reproduction in full-grown colonies naturally infested with V. destructor. Measurements were repeated five times per year over the course of 3 years. The reproductive success of mites as well as the recapping frequency clearly followed seasonal patterns. Thereby, reproductive failure of mites at the cell level was constantly increased in case of recapping. Interestingly, this did not apply to the occurrence of infertile mites. In line with this, recapping activity in fertile cells was most frequent in brood ages in which mite offspring would be expected. Our results suggest that mite offspring is the main target of recapping. This, in turn, leads to a significantly reduced reproductive success of the parasite.
Topics: Bees; Animals; Varroidae; Seasons; Reproduction; Fertility; Host-Parasite Interactions
PubMed: 38110489
DOI: 10.1038/s41598-023-49688-9 -
Journal of Comparative Physiology. A,... Jul 2023
PubMed: 37433949
DOI: 10.1007/s00359-023-01655-5 -
Proceedings of the National Academy of... Feb 2024Visually guided reaching, a regular feature of human life, comprises an intricate neural control task. It includes identifying the target's position in 3D space, passing...
Visually guided reaching, a regular feature of human life, comprises an intricate neural control task. It includes identifying the target's position in 3D space, passing the representation to the motor system that controls the respective appendages, and adjusting ongoing movements using visual and proprioceptive feedback. Given the complexity of the neural control task, invertebrates, with their numerically constrained central nervous systems, are often considered incapable of this level of visuomotor guidance. Here, we provide mechanistic insights into visual appendage guidance in insects by studying the probing movements of the hummingbird hawkmoth's proboscis as they search for a flower's nectary. We show that visually guided proboscis movements fine-tune the coarse control provided by body movements in flight. By impairing the animals' view of their proboscis, we demonstrate that continuous visual feedback is required and actively sought out to guide this appendage. In doing so, we establish an insect model for the study of neural strategies underlying eye-appendage control in a simple nervous system.
Topics: Animals; Humans; Psychomotor Performance; Movement; Insecta; Feedback, Sensory; Visual Perception
PubMed: 38285936
DOI: 10.1073/pnas.2306937121 -
Proceedings. Biological Sciences Dec 2023Many microbes interact with one another, but the difficulty of directly observing these interactions in nature makes interpreting their adaptive value complicated. The...
Many microbes interact with one another, but the difficulty of directly observing these interactions in nature makes interpreting their adaptive value complicated. The social amoeba forms aggregates wherein some cells are sacrificed for the benefit of others. Within chimaeric aggregates containing multiple unrelated lineages, cheaters can gain an advantage by undercontributing, but the extent to which wild has adapted to cheat is not fully clear. In this study, we experimentally evolved in an environment where there were no selective pressures to cheat or resist cheating in chimaeras. lines grown in this environment evolved reduced competitiveness within chimaeric aggregates and reduced ability to migrate during the slug stage. By contrast, we did not observe a reduction in cell number, a trait for which selection was not relaxed. The observed loss of traits that our laboratory conditions had made irrelevant suggests that these traits were adaptations driven and maintained by selective pressures faces in its natural environment. Our results suggest that faces social conflict in nature, and illustrate a general approach that could be applied to searching for social or non-social adaptations in other microbes.
Topics: Dictyostelium; Social Evolution
PubMed: 38113942
DOI: 10.1098/rspb.2023.1722 -
Science Advances Jun 2024Like other group-living species, humans often cooperate more with an in-group member than with out-group members and strangers. Greater in-group favoritism should imply...
Like other group-living species, humans often cooperate more with an in-group member than with out-group members and strangers. Greater in-group favoritism should imply that people also compete less with in-group members than with out-group members and strangers. However, in situations where people could invest to take other's resources and invest to protect against exploitation, we observed the opposite. Akin to what in other species is known as the "nasty neighbor effect," people invested more when facing an in-group rather than out-group member or stranger across 51 nations, in different communities in Kenya, and in representative samples from the United Kingdom. This "nasty neighbor" behavior is independent of in-group favoritism in trust and emerges when people perceive within-group resource scarcity. We discuss how to reconcile that humans exhibit nastiness and favoritism toward in-group members with existing theory on in-group favoritism.
Topics: Humans; Kenya; United Kingdom; Cooperative Behavior; Male; Female; Social Behavior; Trust
PubMed: 38924403
DOI: 10.1126/sciadv.adm7968 -
Journal of Comparative Physiology. A,... Mar 2024Bees are known for their ability to forage with high efficiency. One of their strategies to avoid unproductive foraging is to be at the food source at the right time of... (Review)
Review
Bees are known for their ability to forage with high efficiency. One of their strategies to avoid unproductive foraging is to be at the food source at the right time of the day. Approximately one hundred years ago, researchers discovered that honeybees have a remarkable time memory, which they use for optimizing foraging. Ingeborg Beling was the first to examine this time memory experimentally. In her doctoral thesis, completed under the mentorship of Karl von Frisch in 1929, she systematically examined the capability of honeybees to remember specific times of the day at which they had been trained to appear at a feeding station. Beling was a pioneer in chronobiology, as she described the basic characteristics of the circadian clock on which the honeybee's time memory is based. Unfortunately, after a few years of extremely productive research, she ended her scientific career, probably due to family reasons or political pressure to reduce the number of women in the workforce. Here, we present a biographical sketch of Ingeborg Beling and review her research on the time memory of honeybees. Furthermore, we discuss the significance of her work, considering what is known about time memory today - nearly 100 years after she conducted her experiments.
Topics: Animals; Bees; Feeding Behavior; Food; History, 20th Century
PubMed: 38472409
DOI: 10.1007/s00359-024-01691-9 -
PloS One 2023Allonursing is the nursing of the offspring of other mothers. Cooperation is an emergent property of evolved decision rules. Cooperation can be explained by at least...
Allonursing is the nursing of the offspring of other mothers. Cooperation is an emergent property of evolved decision rules. Cooperation can be explained by at least three evolved decision rules: 1) direct reciprocity, i.e. help someone who previously helped you, 2) kin discrimination, i.e. preferentially direct help to kin than to non-kin, and 3) generalized reciprocity, i.e. help anyone if helped by someone. We assessed if semi-domesticated reindeer, Rangifer tarandus, mothers allonursed according to the decision rules of direct reciprocity, generalized reciprocity and kin discrimination over 2 years. To assess if reindeer mothers allonursed according to the direct reciprocity decision rule, we predicted that mothers should give more help to those who previously helped them more often. To assess if reindeer mothers allonursed according to the kin discrimination decision rule, we predicted that help given should increase as pairwise genetic relatedness increased. To assess if reindeer mothers allonursed according to the generalized reciprocity decision rule, we predicted that the overall number of help given by reindeer mothers should increase as the overall number of help received by reindeer mothers increased. The number of help given i) increased as the number of help received from the same partner increased in the 2012 group but not in both 2013 groups, ii) was not influenced by relatedness, and iii) was not influenced by an interaction between the number of help received from the same partner and relatedness. iv) The overall number of help given increased as the overall number of help received increased. The results did not support the prediction that reindeer mothers allonursed according to the kin discrimination decision rule. The results suggest that reindeer mothers may allonurse according to the direct reciprocity and generalized reciprocity decision rules.
Topics: Female; Animals; Humans; Social Behavior; Cooperative Behavior; Reindeer; Mothers
PubMed: 38096314
DOI: 10.1371/journal.pone.0295497 -
PloS One 2024Captive and domestic animals are often required to engage in physical activity initiated or organised by humans, which may impact their body temperature, with...
Captive and domestic animals are often required to engage in physical activity initiated or organised by humans, which may impact their body temperature, with consequences for their health and welfare. This is a particular concern for animals such as elephants that face thermoregulatory challenges because of their body size and physiology. Using infrared thermography, we measured changes in skin temperature associated with two types of physical activity in ten female Asian elephants (Elephas maximus) at an eco-tourism lodge in Nepal. Six elephants took part in an activity relatively unfamiliar to the elephants-a polo tournament-and four participated in more familiar ecotourism activities. We recorded skin temperatures for four body regions affected by the activities, as well as an average skin temperature. Temperature change was used as the response variable in the analysis and calculated as the difference in elephant temperature before and after activity. We found no significant differences in temperature change between the elephants in the polo-playing group and those from the non-polo playing group. However, for both groups, when comparing the average skin body temperature and several different body regions, we found significant differences in skin temperature change before and after activity. The ear pinna was the most impacted region and was significantly different to all other body regions. This result highlights the importance of this region in thermoregulation for elephants during physical activity. However, as we found no differences between the average body temperatures of the polo and non-polo playing groups, we suggest that thermoregulatory mechanisms can counteract the effects of both physical activities the elephants engaged in.
Topics: Animals; Elephants; Female; Skin Temperature; Physical Conditioning, Animal; Body Temperature; Body Temperature Regulation; Thermography
PubMed: 38696403
DOI: 10.1371/journal.pone.0300373 -
Proceedings of the National Academy of... Feb 2024Many animal species rely on the Earth's magnetic field during navigation, but where in the brain magnetic information is processed is still unknown. To unravel this, we...
Many animal species rely on the Earth's magnetic field during navigation, but where in the brain magnetic information is processed is still unknown. To unravel this, we manipulated the natural magnetic field at the nest entrance of desert ants and investigated how this affects relevant brain regions during early compass calibration. We found that manipulating the Earth's magnetic field has profound effects on neuronal plasticity in two sensory integration centers. Magnetic field manipulations interfere with a typical look-back behavior during learning walks of naive ants. Most importantly, structural analyses in the ants' neuronal compass (central complex) and memory centers (mushroom bodies) demonstrate that magnetic information affects neuronal plasticity during early visual learning. This suggests that magnetic information does not only serve as a compass cue for navigation but also as a global reference system crucial for spatial memory formation. We propose a neural circuit for integration of magnetic information into visual guidance networks in the ant brain. Taken together, our results provide an insight into the neural substrate for magnetic navigation in insects.
Topics: Animals; Ants; Learning; Brain; Neuronal Plasticity; Magnetic Phenomena; Homing Behavior; Cues; Desert Climate
PubMed: 38346192
DOI: 10.1073/pnas.2320764121