@article{FlorenLinsenmairMueller2022, author = {Floren, Andreas and Linsenmair, Karl Eduard and M{\"u}ller, Tobias}, title = {Diversity and functional relevance of canopy arthropods in Central Europe}, series = {Diversity}, volume = {14}, journal = {Diversity}, number = {8}, issn = {1424-2818}, doi = {10.3390/d14080660}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-285924}, year = {2022}, abstract = {Although much is known about the ecology and functional importance of canopy arthropods in temperate forests, few studies have tried to assess the overall diversity and investigate the composition and dynamics of tree-specific communities. This has impeded a deeper understanding of the functioning of forests, and of how to maintain system services. Here, we present the first comprehensive data of whole arthropod communities, collected by insecticidal knockdown (fogging) from 1159 trees in 18 study areas in Central Europe during the last 25 years. The data includes 3,253,591 arthropods from 32 taxa (order, suborder, family) collected on 24 tree species from 18 genera. Fogging collects free-living, ectophytic arthropods in approximately the same number as they occur in the trees. To our knowledge, these are the most comprehensive data available today on the taxonomic composition of arboreal fauna. Assigning all arthropods to their feeding guild provided a proxy of their functional importance. The data showed that the canopy communities were regularly structured, with a clear dominance hierarchy comprised of eight 'major taxa' that represented 87\% of all arthropods. Despite significant differences in the proportions of taxa on deciduous and coniferous trees, the composition of the guilds was very similar. The individual tree genera, on the other hand, showed significant differences in guild composition, especially when different study areas and years were compared, whereas tree-specific traits, such as tree height, girth in breast height or leaf cover, explained little of the overall variance. On the ordinal level, guild composition also differed significantly between managed and primary forests, with a simultaneous low within-group variability, indicating that management is a key factor determining the distribution of biodiversity and guild composition.}, language = {en} } @article{SteinCoulibalyBalimaetal.2020, author = {Stein, Katharina and Coulibaly, Drissa and Balima, Larba Hubert and Goetze, Dethardt and Linsenmair, Karl Eduard and Porembski, Stefan and Stenchly, Kathrin and Theodorou, Panagiotis}, title = {Plant-pollinator networks in savannas of Burkina Faso, West Africa}, series = {Diversity}, volume = {13}, journal = {Diversity}, number = {1}, issn = {1424-2818}, doi = {10.3390/d13010001}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-220157}, year = {2020}, abstract = {West African savannas are severely threatened with intensified land use and increasing degradation. Bees are important for terrestrial biodiversity as they provide native plant species with pollination services. However, little information is available regarding their mutualistic interactions with woody plant species. In the first network study from sub-Saharan West Africa, we investigated the effects of land-use intensity and climatic seasonality on plant-bee communities and their interaction networks. In total, we recorded 5686 interactions between 53 flowering woody plant species and 100 bee species. Bee-species richness and the number of interactions were higher in the low compared to medium and high land-use intensity sites. Bee- and plant-species richness and the number of interactions were higher in the dry compared to the rainy season. Plant-bee visitation networks were not strongly affected by land-use intensity; however, climatic seasonality had a strong effect on network architecture. Null-model corrected connectance and nestedness were higher in the dry compared to the rainy season. In addition, network specialization and null-model corrected modularity were lower in the dry compared to the rainy season. Our results suggest that in our study region, seasonal effects on mutualistic network architecture are more pronounced compared to land-use change effects. Nonetheless, the decrease in bee-species richness and the number of plant-bee interactions with an increase in land-use intensity highlights the importance of savanna conservation for maintaining bee diversity and the concomitant provision of ecosystem services.}, language = {en} } @article{FrankSchmittHovestadtetal.2017, author = {Frank, Erik Thomas and Schmitt, Thomas and Hovestadt, Thomas and Mitesser, Oliver and Stiegler, Jonas and Linsenmair, Karl Eduard}, title = {Saving the injured: Rescue behavior in the termite-hunting ant Megaponera analis}, series = {Science Advances}, volume = {3}, journal = {Science Advances}, number = {4}, doi = {10.1126/sciadv.1602187}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-157933}, pages = {e1602187}, year = {2017}, abstract = {Predators of highly defensive prey likely develop cost-reducing adaptations. The ant Megaponera analis is a specialized termite predator, solely raiding termites of the subfamily Macrotermitinae (in this study, mostly colonies of Pseudocanthotermes sp.) at their foraging sites. The evolutionary arms race between termites and ants led to various defensive mechanisms in termites (for example, a caste specialized in fighting predators). Because M. analis incurs high injury/mortality risks when preying on termites, some risk-mitigating adaptations seem likely to have evolved. We show that a unique rescue behavior in M. analis, consisting of injured nestmates being carried back to the nest, reduces combat mortality. After a fight, injured ants are carried back by their nestmates; these ants have usually lost an extremity or have termites clinging to them and are able to recover within the nest. Injured ants that are forced experimentally to return without help, die in 32\% of the cases. Behavioral experiments show that two compounds, dimethyl disulfide and dimethyl trisulfide, present in the mandibular gland reservoirs, trigger the rescue behavior. A model accounting for this rescue behavior identifies the drivers favoring its evolution and estimates that rescuing enables maintenance of a 28.7\% larger colony size. Our results are the first to explore experimentally the adaptive value of this form of rescue behavior focused on injured nestmates in social insects and help us to identify evolutionary drivers responsible for this type of behavior to evolve in animals.}, language = {en} } @article{FlorenKruegerMuelleretal.2015, author = {Floren, Andreas and Kr{\"u}ger, Dirk and M{\"u}ller, Tobias and Dittrich, Marcus and Rudloff, Renate and Hoppe, Bj{\"o}rn and Linsenmair, Karl Eduard}, title = {Diversity and interactions of wood-inhabiting fungi and beetles after deadwood enrichment}, series = {PLoS ONE}, volume = {10}, journal = {PLoS ONE}, number = {11}, doi = {10.1371/journal.pone.0143566}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-145129}, pages = {e0143566}, year = {2015}, abstract = {Freshly cut beech deadwood was enriched in the canopy and on the ground in three cultural landscapes in Germany (Swabian Alb, Hainich-Dun, Schorfheide-Chorin) in order to analyse the diversity, distribution and interaction of wood-inhabiting fungi and beetles. After two years of wood decay 83 MOTUs (Molecular Operational Taxonomic Units) from 28 wood samples were identified. Flight Interception Traps (FITs) installed adjacent to the deadwood enrichments captured 29.465 beetles which were sorted to 566 species. Geographical 'region' was the main factor determining both beetle and fungal assemblages. The proportions of species occurring in all regions were low. Statistic models suggest that assemblages of both taxa differed between stratum and management praxis but their strength varied among regions. Fungal assemblages in Hainich-Dun, for which the data was most comprehensive, discriminated unmanaged from extensively managed and age-class forests (even-aged timber management) while canopy communities differed not from those near the ground. In contrast, the beetle assemblages at the same sites showed the opposite pattern. We pursued an approach in the search for fungus-beetle associations by computing cross correlations and visualize significant links in a network graph. These correlations can be used to formulate hypotheses on mutualistic relationships for example in respect to beetles acting as vectors of fungal spores.}, language = {en} } @article{HsiehLinsenmair2012, author = {Hsieh, Yu-Lung and Linsenmair, Karl Eduard}, title = {Seasonal dynamics of arboreal spider diversity in a temperate forest}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-75158}, year = {2012}, abstract = {Measuring and estimating biodiversity patterns is a fundamental task of the scientist working to support conservation and informmanagement decisions.Most biodiversity studies in temperate regions were often carried out over a very short period of time (e.g., a single season) and it is often—at least tacitly—assumed that these short-termfindings are representative of long-termgeneral patterns.However, should the studied biodiversity pattern in fact contain significant temporal dynamics, perhaps leading to contradictory conclusions. Here, we studied the seasonal diversity dynamics of arboreal spider communities dwelling in 216 European beeches (Fagus sylvatica L.) to assess the spider community composition in the following seasons: two cold seasons (I:November 2005-January 2006; II: February-April) and two warm seasons (III: May-July; IV: August-October). We show that the usually measured diversity of the warmseason community (IV: 58 estimated species) alone did not deliver a reliable image of the overall diversity present in these trees, and therefore, we recommend it should not be used for sampling protocols aimed at providing a full picture of a forest's biodiversity in the temperate zones. In particular, when the additional samplings of other seasons (I, II, III) were included, the estimated species richness nearly doubled (108). Community I possessed the lowest diversity and evenness due to the harsh winter conditions: this community was comprised of one dominant species together with several species low in abundance. Similarity was lowest (38.6\%) between seasonal communities I and III, indicating a significant species turnover due to recolonization, so that community III had the highest diversity. Finally, using nonparametric estimators, we found that further sampling in late winter (February-April) is most needed to complete our inventory. Our study clearly demonstrates that seasonal dynamics of communities should be taken into account when studying biodiversity patterns of spiders, and probably forest arthropods in general.}, subject = {Biologie}, language = {en} } @article{DossoYeoKonateetal.2012, author = {Dosso, Kanvaly and Yeo, Kolo and Konate, Souleymane and Linsenmair, Karl Eduard}, title = {Importance of protected areas for biodiversity conservation in central Cote d'Ivoire: Comparison of termite assemblages between two neighboring areas under differing levels of disturbance}, series = {Journal of Insect Science}, volume = {12}, journal = {Journal of Insect Science}, number = {131}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-133218}, year = {2012}, abstract = {To highlight human impact on biodiversity in the Lamto region, termites were studied with regard to their use as bio-indicators of habitat change in the tropics. Using a standardized method, termites were sampled in the three most common habitat types, i.e., in semi-deciduous forest, savanna woodland, and annually burned savanna, all inside Lamto Reserve and its surrounding rural domain. Termite species richness fell from 25 species in the Lamto forest to 13 species in the rural area, involving strong modification in the species composition (species turnover = 59 \%). In contrast, no significant change in diversity was found between the Lamto savannas and the rural ones. In addition, the relative abundance of termites showed a significantly greater decline in the rural domain, even in the species Ancistrotermes cavithorax (Sjostedt) (Isoptera: Termitidae), which is known to be ecologically especially versatile. Overall, the findings of this study suggest further investigation around Lamto Reserve on the impact of human activities on biodiversity, focusing on forest conversion to land uses (e.g. agricultural and silvicultural systems).}, language = {en} } @article{FialaGrunskyMaschwitzetal.1994, author = {Fiala, Brigitte and Grunsky, Harald and Maschwitz, Ulrich and Linsenmair, Karl Eduard}, title = {Diversity of ant-plant interactions: Protective efficacy in Macaranga species with different degrees of ant-association.}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-32905}, year = {1994}, abstract = {The pioneer tree Macaranga in SE Asia has developed manyfold associations with ants. The genus comprises all stages of interaction with ants, from facultative relationships to obligate myrmecophytes. Only myrmecophytic Macaranga offer nesting space for ants and are associated with a specific ant partner. The nonmyrmecophytic species are visited by a variety of different ant species which are attracted by extrafloral nectaries (EFN) and food bodies. Transitional Macaranga species like M. hosei are colonized later in their development due to their stem structure. Before the colonization by their specific Crematogaster partner the young plants are visited by different ant species attracted by EFN. These nectaries are reduced and food body production starts as soon as colonization becomes possible. We demonstrated earlier that obligate ant partners can protect their Macaranga plants against herbivore damage and vine cover. In this study we focused on nonspecific interactions and studied M. tanarius and M. hosei, representing a non-myrmecophyte and a transitional species respectively. In ant exclusion experiments both M. tanarius and M. hosei suffered significantly higher mean leaf damage than controls, 37\% versus 6\% in M. hosei, 16\% versus 7\% in M. tanarius. M. tanarius offers both EFN and food bodies so that tests for different effects of these two food rewards could be conducted. Plants with food bodies removed but with EFN remaining had the lowest mean increase of herbivore damage of all experimental groups. Main herbivores on M. hosei were mites and caterpillars. Many M. tanarius plants were infested by a shootborer. Both Macaranga species were visited by various ant species. Crematogaster spp. being the most abundant. We found no evidence for any specific relationships. The results of this study strongly support the hypothesis that non-specific, facultative associations with ants can be advantageous for Macaranga plants. Food bodies appear to have lower attractive value for opportunistic ants than EFN and may require a specific dietary adaptation. This is also indicated by the fact that food body production in the transitional M. hosei does not start before stem structure allows a colonization by the obligate Crematogaster species. M. hosei thus benefits from facultative association with a variety of ants until it produces its first domatia and can be colonized by its obligate mutualist.}, language = {en} } @article{MaschwitzFialaLinsenmair1994, author = {Maschwitz, Ulrich and Fiala, Brigitte and Linsenmair, Karl Eduard}, title = {Clerodendrum fistulosum (Verbenanceae), an unspecific myrmecophyte from Borneo with spontaneously opening domatia}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31013}, year = {1994}, abstract = {Clerodendrumjistulosum Becc. is a true myrmecophyte as it offers nesting space for ants in hollow intemodes. In contrast to previous reports our investigations proved that these domatia open by themselves, thus providing cavities for a variety of different ant species. In Sarawak, Malaysia, we did not find an obligate relationship between C. jistulosum and a specific ant-partner. For comparison, studies on herbarium material of other Clerodendrum species were carried out a further species, C. deflexum from the Malay Peninsula and Sumatra presumably also is myrmecophytic.}, language = {en} } @article{Linsenmair1994, author = {Linsenmair, Karl Eduard}, title = {Biologische Vielfalt und {\"o}kologische Stabilit{\"a}t}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31157}, year = {1994}, abstract = {No abstract available}, language = {en} } @article{SchmuckGeiseLinsenmair1994, author = {Schmuck, R. and Geise, W. and Linsenmair, Karl Eduard}, title = {Life cycle strategies and physiological adjustments of Reedfrog Tadpoles (Amphibia, Anura, Hyperoliidae) in relation to environmental conditions.}, url = {http://nbn-resolving.de/urn:nbn:de:bvb:20-opus-31009}, year = {1994}, abstract = {The relationship between different degrees of intraspecific crowding of reedfrog tadpoles and their physiological responses to a deterioration of the natal pond water quality was examined under laboratory conditions. Tadpoles that were reared at a lower density metamorphosed significantly earlier than those raised at a higher density. As density increases, the average body length at metamorphosis decreases. However, at low tadpole density, a significantly higher diversity of body size classes among freshly metamorphosed froglets was observed than under more crowded conditions. Mortality increased during metamorphic climax and was inversely correlated with the tadpole density. In ephemeral ponds, an accumulation of nitrogenous wastes from metabolic processes and/or a concentration by evaporation in prolonged rainless periods can pose a considerable chemical stress to reedfrog tadpoles. Hyperolius viridiflavus ommatostictus responded to an increasing ammonia concentration with an activity increase of the ornithine cycle (intensified urea synthesis). hi contrast, Hyperolius marmoratus taeniatus exhibited a strong tolerance against high ammonia levels. A deterioration of the natal pond water quality caused H. v. ommatostictus and H. v. nitidulus tadpoles to adjust to harsher climatic conditions at the time of metamorphosis. This physiological preadjustment enabled the froglets to start feeding and growing immediately after metamorphosis even at low air humidity and rare precipitation events. In contrast, froglets that were raised in daily refreshed water exhibited high mortality rates if subjected to identical conditions. As one possible indicator of the actual climatic conditions prevailing in the surrounding terrestrial habitat, fluctuations in the water ammonia level are discussed.}, language = {en} }