Native Bees vs Honey Bees: The Fitness Fight

A recent study conducted by Curtin University has shed light on the struggles faced by Australian native bees due to the presence of European honey bees. Led by Dr Kit Prendergast from the School of Molecular and Life Sciences, the research found that high densities of honey bees can significantly impact the reproductive success and survival traits of native cavity-nesting bees.

The study utilized specially designed wooden “bee hotels” located in 14 urban bushland and garden sites in Perth, Western Australia. These bee hotels served as a platform to assess how honey bee density influenced key indicators of native bee health and reproduction over two Spring-to-Summer bee seasons.

Dr Prendergast explained that the research aimed to understand the impact of honey bees on native bees by using these bee hotels as research tools. “Bee hotels are not just a way to give bees a place to nest; they’re powerful tools that let us measure how well native bees are surviving and reproducing in different environments,” she stated.

The study involved analyzing 1000 native bee nests, providing valuable insights into the fitness of at least 25 species. The results showed that areas with higher honey bee densities were associated with reduced reproductive success, increased offspring mortality, and smaller male offspring in native bees.

Furthermore, the research found that honey bees tend to forage from a wider range of sources, including exotic plants. This overlap in pollen use was linked to lower offspring numbers in native bees, indicating that honey bees can negatively impact local ecosystems and contribute to declines in native bee populations.

Dr Prendergast emphasized the importance of managing honey bee densities carefully, especially in areas of high conservation value or where native pollinators are already under pressure from factors such as urbanization. She suggested that future research should explore whether adjusting honey bee numbers or increasing the diversity of flowering plants could help mitigate their impact on native bees.

The study was conducted as part of Dr Prendergast’s PhD research at Curtin and received funding from various organizations, including the City of Stirling, the Australian Wildlife Society, Hesperia, and the Forrest Research Foundation. The findings add to growing evidence that we need to carefully manage honey bee populations to protect native pollinators and maintain ecosystem balance.

The molecular switches that regulate vital functions in our bodies are called G protein-coupled receptors (GPCRs). These crucial molecules embedded in the cell membrane transmit signals from outside to inside the cell. Due to their vast diversity and essential role, GPCRs have become the target of many drugs, including painkillers, heart medications, and diabetes treatments. In fact, one-third of all approved drugs act on GPCRs.

Until recently, scientists knew little about how these receptors functioned. However, researchers at the University of Basel have now uncovered a fundamental mechanism behind GPCR activity using a novel method inspired by GPS technology. This innovative approach enables scientists to track the movements of a GPCR and observe it in action, providing valuable insights for designing more effective drugs with fewer side effects.

The study focused on the β1-adrenergic receptor, a key player in the cardiovascular system targeted by beta-blockers. Using GPS-inspired Nuclear Magnetic Resonance (NMR) technology, researchers precisely pinpointed the position of about one hundred sites within this receptor and monitored their motions during activation. The findings reveal that the receptor does not simply switch between static “off” and “on” states but instead sits in a dynamic conformational equilibrium between inactive, preactive, and active states.

The binding of agonists like isoprenaline shifts the receptor more towards the active state, while beta-blockers lock it mostly in the inactive state. The researchers also discovered that very small atomic modifications can fine-tune the signaling output of the receptor. This understanding at the atomic level allows scientists to truly comprehend how these receptors work and may provide guidance for designing drugs with desired outputs.

In summary, this groundbreaking research has bridged the gap between the static structures of GPCRs and their function by tracking in detail how the receptor dynamically moves during activation. With this knowledge, scientists can now design more effective drugs that target specific aspects of GPCR activity, ultimately improving human health outcomes.

Human activities have been found to have a significant impact on biodiversity, extending far beyond the areas directly affected by human presence. A recent study has revealed that even hundreds of kilometers away from the source of human activity, plant diversity is significantly reduced.

The concept of “dark diversity” was first introduced in 2011 by researchers at the University of Tartu (Estonia). It refers to the proportion of species that could potentially inhabit a given area but are not currently present. A study involving the UPV/EHU has found that this dark diversity increases in regions with greater human activity.

The research team analyzed nearly 5,500 locations across the world, comparing the plant species present in different habitats to identify dark diversity. The innovative methodology allowed them to estimate potential plant diversity and compare it with actual presence. The results show a previously unknown effect of human activities on biodiversity.

In areas with little human impact, natural habitats contain approximately one-third of the potential species. However, in regions with high human impact, habitats tend to include only one-fifth of the potential species. This suggests that traditional methods for estimating biodiversity may underestimate the true effect of human impact.

The DarkDivNet network was launched in 2018 based on the original idea of Professor Meelis Pärtel of the University of Tartu and lead author of the study. The network has since gathered research groups from around the world to sample as many regions as possible. A team from the UPV/EHU chose the Gorbeia Nature Reserve as a sampling site, targeting beech forests and moors.

The degree of human impact was measured using the Human Footprint Index, which takes into account factors such as population density, land use changes, and infrastructure construction (roads). The study found that the human footprint index negatively affects plant diversity in a locality within a radius of several hundred kilometers.

The researchers highlighted that the results are alarming because they show that human disturbance exerts a much greater impact than initially thought, even reaching protected areas far from the source of human impact. Pollution, deforestation, overgrazing, and forest fires can exclude plant species from their natural habitats, preventing them from recolonizing.

However, the negative influence of human activity was less pronounced when at least one-third of a region’s area remained well preserved, which supports the global goal of protecting 30% of the planet’s surface. This study emphasizes the importance of maintaining healthy ecosystems beyond nature reserves and highlights the concept of dark diversity as a useful tool for assessing the status of ecosystems undergoing restoration.

The findings suggest that it is crucial to consider the impact of human activity on plant diversity, even in areas far from the source of disturbance. By doing so, we can take proactive measures to protect and restore ecosystems, ensuring the long-term survival of plant species and maintaining healthy biodiversity.