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The distribution of various evolutionary lineages of Apis mellifera subspecies in Africa is still controversial. We sampled honeybees from eight coastal locations and three Saharan oases in Libya and analyzed mtDNA variability with restriction fragment length polymorphisms and the sequence of the tRNAleu-cox2 intergenic region. Haplotypes belonging to the oriental O evolutionary lineage, including four which are newly described, were detected in all investigated locations. Haplotypes belonging to the European M lineage were rarely detected, probably reflecting the effect of sporadic importations. Honeybees belonging to the A lineage were detected in Al Aziziyah and Zlitan close to the Tunisian border. The distribution of the O lineage extends westward up to the border between Libya and Tunisia, a contact area between the O and A lineages. Various Libyan honeybee populations in Saharan oases are characterized by novel and unique haplotypes (O4, O5, O5′ and O5″). These might be natural relic populations that became isolated when the North African Sahara desert was still grassland (0.126–0.168 Myr ago)., Depto. de Biodiversidad, Ecología y Evolución, Fac. de Ciencias Biológicas, TRUE, pub

In a cross-disciplinary project (LEGATO) combining inter- and transdisciplinary methods, we quantify the dependency of rice-dominated socio-ecological systems on ecosystem functions (ESF) and the ecosystem services (ESS) the integrated system provides. In the collaboration of a large team including geo- and bioscientists, economists, political and cultural scientists, the mutual influences of the biological, climate and soil conditions of the agricultural area and its surrounding natural landscape have been analysed. One focus was on sociocultural and economic backgrounds, another on local as well as regional land use intensity and biodiversity, and the potential impacts of future climate and land use change. LEGATO analysed characteristic elements of three service strands defined by the Millennium Ecosystem Assessment (MA): (a) provisioning services: nutrient cycling and crop production; (b) regulating services: biocontrol and pollination; and (c) cultural services: cultural identity and aesthetics. However, in line with much of the current ESS literature, what the MA called supporting services is treated as ESF within LEGATO. As a core output, LEGATO developed generally applicable principles of ecological engineering (EE), suitable for application in the context of future climate and land use change. EE is an emerging discipline, concerned with the design, monitoring and construction of ecosystems and aims at developing strategies to optimise ecosystem services through exploiting natural regulation mechanisms instead of suppressing them. Along these lines LEGATO also aims to create the knowledge base for decision-making for sustainable land management and livelihoods, including the provision of the corresponding governance and management strategies, technologies and system solutions.

Phengaris (Maculinea) butterflies are social parasites of Myrmica ant colonies. Larvae of the parasite are adopted by the ant workers into the colonies. Apparently, chemical signals are used by Phengaris nausithous Bergsträsser larvae to mimic those of the host brood to be recognized by the ants. In the present study, chemical extracts of ant brood and butterfly larvae using four different solvents are tested in behavioural choice assays in search of compounds involved in the adoption process. Tetracosane is the main shared compound in all brood extracts of Myrmica rubra L. and in all larvae of P. nausithous. The attractiveness of tetracosane for M. rubra workers is confirmed by testing synthetic tetracosane in behavioural choice assays, suggesting that the adoption ritual may be initiated by tetracosane.

Evolutionary theory predicts that high genetic variation maintains plasticity in a species’ response to parasite pressure. However, higher genetic diversity might also cause easier infiltration by social parasites, because odour diversity is high and nest-mate recognition poor. Here we test if the obligate myrmecophile Lycaenid butterfly Phengaris nausithous, a parasite of colonies of the highly polygynous ant Myrmica rubra causes local adaptation by enhancing genetic variance in parasitized versus non parasitized ant populations M. rubra colonies from six infested and three uninfested sites were assayed at five microsatellite loci to quantify genetic variation. Our results reveal isolation by distance and a significantly enhanced intracolonial variance due to the parasite pressure.

Larvae of Phengaris (Maculinea) butterflies are adopted by Myrmica workers and are obligate myrmecophiles. Brood recognition by Myrmica rubra workers was tested for concolonial larvae (M. rubra) versus allocolonial larvae (M. rubra and P. nausithous) to assay the mimetic efficiency of P. nausithous. In addition, we tested M. rubra ant colonies from different populations with and without the presence of Phengaris, to test for potential local adaptation in adoption behaviour. We show that M. rubra can distinguish between nest-mate and foreign larvae as well as between P. nausithous and their own larvae. Workers from the allopatric population inspected and rejected more P. nausithous larvae than workers from the sympatric population. This might reflect a local host adaptation in which the social parasite more efficiently mimes its sympatric host ants than allopatric ones.

Bumblebees are of profound ecological importance because of the pollination services they provide in natural and agricultural ecosystems. Any decline of these pollinators is therefore of great concern for ecosystem functioning. Increased parasite pressures have been discussed as a major factor for the loss of pollinators. One of the main parasites of bumblebees is Nosema bombi, an intracellular microsporidian parasite with considerable impact on the vitality of the host. Here we study the effect of host colony density and host genetic variability on N. bombi infections in natural populations of the bumblebee Bombus terrestris. We sampled males and workers from six B. terrestris populations located in an agricultural landscape in Middle Sweden to determine the prevalence and degree of N. bombi infections. All individuals were genotyped with five microsatellite markers to infer the colony densities in the sampled populations and the genetic variability of the host population. We confirmed that genetic variability and sex significantly correlate with the degree of infection with N. bombi. Males and workers with lower genetic variability had significantly higher infection levels than average. Also colony density had a significant impact on the degree of infection, with high density populations having higher infected individuals.

Background Cooperation and conflict in social insects are closely linked to the genetic structure of the colony. Kin selection theory predicts conflict over the production of males between the workers and the queen and between the workers themselves, depending on intra-colonial relatedness but also on other factors like colony efficiency, sex ratios, cost of worker reproduction and worker dominance behaviour. In most bumblebee (Bombus) species the queen wins this conflict and often dominates male production. However, most studies in bumblebees have been conducted with only a few selected, mostly single mated species from temperate climate regions. Here we study the genetic colony composition of the facultative polyandrous neotropical bumblebee Bombus wilmattae, to assess the outcome of the queen-worker conflict over male production and to detect potential worker policing. Results A total of 120 males from five colonies were genotyped with up to nine microsatellite markers to infer their parentage. Four of the five colonies were queen right at point of time of male sampling, while one had an uncertain queen status. The workers clearly dominated production of males with an average of 84.9% +/- 14.3% of males being worker sons. In the two doubly mated colonies 62.5% and 96.7% of the male offspring originated from workers and both patrilines participated in male production. Inferring the mother genotypes from the male offspring, between four to eight workers participated in the production of males. Conclusions In this study we show that the workers clearly win the queen-worker conflict over male production in B. wilmattae, which sets them apart from the temperate bumblebee species studied so far. Workers clearly dominated male production in the singly as well the doubly mated colonies, with up to eight workers producing male offspring in a single colony. Moreover no monopolization of reproduction by single workers occurred.

This paper reviews conflicts between biodiversity conservation and agricultural activities in agricultural landscapes and evaluates strategies to reconcile such conflicts. Firstly, a historical perspective on the development of conflicts related to biodiversity in agricultural landscapes is presented. Secondly, recent trends in agricultural policies of the European Union that contribute to biodiversity decline in agricultural landscapes are considered. Three major processes responsible for creating biodiversity-related conflicts are described: the intensification of agriculture, the abandonment of marginally productive but High Nature Value Farmland, and the changing scale of agricultural operations. Conflicts created by these processes and approaches to their reconciliation are identified, emphasizing the need for monitoring as an integral part of conflict reconciliation strategies. A generic approach comprising three types of monitoring is developed for measuring success of reconciliation strategies: monitoring of the intensity of the conflict between stakeholders, of the social and economic effects on farmers, and of the status and trends in biodiversity. Surprisingly, we found no evidence in the literature that the first type of monitoring has ever been undertaken for biodiversity-related conflicts in agricultural landscapes. For each type of monitoring, suitable indicators are outlined. Finally, challenges for conflict management in agricultural landscapes are summarized.