Project description:Egg rejection often involves a cognitive process of recognizing foreign eggs, which can vary not only between species or among different individuals of the same species, but also within the same individual during different breeding stages, leading to markedly different responses to parasitic eggs. We conducted a comparative study in Wuhan, Hubei, and Fusong, Jilin, China, on the recognition and rejection behavior of azure-winged magpies (Cyanopica cyanus) at different breeding stages (pre-egg-laying, one-host-egg, multi-host-egg and early incubation stages). In the Fusong population, there was a significant difference in the rejection rate of model eggs by azure-winged magpies at different stages of the egg-laying period. During the one-host-egg stage, the rejection rate (63.6%) was significantly lower than that during the pre-egg-laying stage (85.7%) and the multi-host-egg stage (100%). The population of azure-winged magpies in Wuhan exhibited a 100% rejection rate towards model eggs during the pre-egg-laying stage. Furthermore, during the incubation stage, azure-winged magpies were able to accurately recognize and reject foreign eggs even when those were in majority. This indicates that azure-winged magpies employ a template-based recognition mechanism rather than relying on discordance mechanism for recognition after the onset of incubation. This study suggests that while azure-winged magpies can truly recognize their own eggs, different breeding stages still influence their rejection response towards parasitic eggs, especially during the pre-egg-laying and egg laying stages.
Project description:One of the contemporary hypotheses concerning the evolution of human altruism is the cooperative breeding hypothesis (CBH) which has recently been tested in non-human primates. Using a similar paradigm, we investigated prosociality in a cooperatively breeding corvid, the azure-winged magpie. We found that the magpies delivered food to their group members at high rates, and unlike other corvids, they did so without any cues provided by others. In two control conditions, the magpies stopped participating over time, indicating that they learned to discriminate prosocial tests from controls. Azure-winged magpies are thus the first birds that experimentally show proactive prosociality. Our findings are in line with the CBH; however, additional corvid species need to be tested in this promising paradigm.
Project description:The azure-winged magpie (AWM), Cyanopica cyanus, is found in Asia and Iberia. This remarkable disjunct distribution has been variously explained by either the sixteenth-century introduction of birds into Iberia from the Far East, or by the loss of individuals from the central part of their range as a result of Pleistocene glaciations. We have used the mitochondrial control region to undertake a molecular phylogenetic analysis of the AWM, with sequences examined from individuals collected from across the current distribution range and incorporating representatives of all currently defined subspecies. The Western birds are genetically distinct from their Asian congeners and their divergence is basal in the phylogenetic tree. This indicates that the AWM is native to Iberia and not the result of a recent introduction from Asia. In Asia, two major mitochondrial DNA lineages were identified. These correspond to an Inland Asia group and a Pacific Seaboard group, and are separated topographically by the Da Hingan Ling mountains and the Yellow Sea. Molecular clock estimates suggest that these divergences are associated with Pleistocene glaciations. Furthermore, our data do not support the current classification of the AWM into 10 subspecies, as defined based on morphology and geographical distribution.
Project description:Bird nests are crucial for reproductive success since they serve as structures to hold the eggs and nestlings safely. Therefore, the structural characteristics of bird nests have optimally evolved to maximize reproductive success, which are known to be affected by various factors. We gathered information on the nest characteristics such as nest structure and constituent materials in the colonial breeding Azure-winged magpie (Cyanopica cyanus) and investigated the relationship between ecologically relevant factors and the size and mass of the nests. The Azure-winged magpie nest can be deconstructed into an outer nest and an inner cup, and the type and mass of materials used for the construction of each part varies. Compared to the inner cup, the outer nest, which constitutes the overall shape of the nest, is composed of relatively harder materials, such as branches and soil. In contrast, the inner cup, which is the part where birds directly incubate eggs and raise nestlings, is composed of more flexible and softer materials, such as fiber and moss. We found that there was no relationship between nest characteristics and ecologically relevant factors. However, as the breeding season progressed, the volume of the inner cup decreased with increasing ambient temperatures. Our results show that Azure-winged magpies use differing materials for structurally distinct parts of the nests during construction. The results also indirectly suggest that the choice regarding the amount of insulating materials relative to changing temperatures during the breeding season may be one of the more significant adaptive strategies in the nest-building behaviors of Azure-winged magpies.
Project description:Predation events are an important key factor determining the survival and reproduction of prey species. To cope, prey species have evolved various anti-predator strategies, including mechanisms for accurate predator identification and distinguishing predator types and risk levels. Birds rely on visual, auditory, and olfactory cues to perceive and categorize predators. However, previous studies have focused on single sensory modalities and have largely been conducted during breeding seasons. Thus, analyses of the accuracy and differences in predator recognition cues, especially during non-breeding periods, are needed. In this study, predator recognition in Azure-winged Magpies (Cyanopica cyanus) was evaluated during the non-breeding season. We examined responses to two predators, Common Kestrel (Falco tinnunculus) and Domestic Cat (Felis catus), and two non-predators, Oriental Magpie (Pica serica) and Oriental Turtle Dove (Streptopelia orientalis). Using specimens and playback experiment, the ability of Azure-winged magpies to identify threats through both visual and auditory cues was evaluated. The results showed that Azure-winged Magpies can identify predator types through both visual and auditory cues, accurately distinguish threat levels, and adjust their foraging behavior accordingly. Notably, they exhibited the strongest anti-predator response to Domestic Cats (frequently encountered under natural conditions), as evidenced by longer observation times, shorter foraging duration, and quicker flight responses. The results indicate that Azure-winged Magpies can correctly identify predator types and threat levels through both visual and auditory cues and exhibit stronger anti-predator behaviors with increasing apparent threat levels.
Project description:This study aims to investigate the DNA methylation patterns at transcription factor binding regions and their evolutionary conservation with respect to binding activity divergence. We combined newly generated bisulfite-sequencing experiments in livers of five mammals (human, macaque, mouse, rat and dog) and matched publicly available ChIP-sequencing data for five transcription factors (CEBPA, HNF4a, CTCF, ONECUT1 and FOXA1). To study the chromatin contexts of TF binding subjected to distinct evolutionary pressures, we integrated publicly available active promoter, active enhancer and primed enhancer calls determined by profiling genome wide patterns of H3K27ac, H3K4me3 and H3K4me1.