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Aufsatz
The velvet worm brain unveils homologies and evolutionary novelties across panarthropods
(2022-01-25)
Background:
The evolution of the brain and its major neuropils in Panarthropoda (comprising Arthropoda, Tardigrada and Onychophora) remains enigmatic. As one of the closest relatives of arthropods, onychophorans are regarded as indispensable for a broad understanding of the evolution of panarthropod organ systems, including the brain, whose anatomical and functional organisation is often used to gain insights into evolutionary relations. However, while numerous recent studies have clarified the organisation of many ...
Aufsatz
Phenotypic and genetic diversity of domestic yak (Bos grunniens) in high-altitude rangelands of Gilgit-Baltistan, Pakistan
(2022-07-04)
Due to climate change, irrigated agriculture may become restricted in the mountain valleys in northern Pakistan in the future. Hence, the importance of yak (Bos grunniens) keeping in the mountain ranges as risk-mitigating strategy for mountain dwellers will potentially increase. However, little is known about the current status of the domestic yak in this region. We therefore used phenotypic characteristics and 13 microsatellite loci to determine the phenotypic differences and the level of genetic differentiation ...
Aufsatz
Pollen metabarcoding of museum specimens and recently collected bumblebees (Bombus) indicates foraging shifts
(2023-07-05)
Landscape changes, over time, lead to changes of floral resources available to pollinators, which in turn may result in the disappearance of ecologically specialized species. Here, we use pollen metabarcoding to infer historic and recent interactions between plants and bumblebees (Bombus). Bumblebees from Cuxhaven (Germany) were sampled from historical museum collections (1968/69) and in the field (2019). Pollen attached to their bodies was barcoded using multiple plant markers (ITS1, ITS2 and trnL-P6 loop). Our ...
Aufsatz
Why has animal science not led to improved farm animal health and welfare?
(2024-01-05)
To sustain the economic viability of a livestock farm in a global market, characterised by a price undercutting competition, farmers are forced to adapt to what the market demands. At the same time, they have to care for the functionality of the farm system as a whole and of the subsystems, such as the farm animals, so that they for their part they can contribute to an economic success. Now, that animal health and welfare (AHW) has become an increasingly important issue for citizens and consumers, not only the decision ...
Aufsatz
The Internal Structure of the Velvet Worm Projectile Slime: A Small-Angle Scattering Study
(2023-02-24)
For prey capture and defense, velvet worms eject an adhesive slime which has been established as a model system for recyclable complex liquids. Triggered by mechanical agitation, the liquid bio-adhesive rapidly transitions into solid fibers. In order to understand this mechanoresponsive behavior, here, the nanostructural organization of slime components are studied using small-angle scattering with neutrons and X-rays. The scattering intensities are successfully described with a three-component model accounting for ...
Aufsatz
Human‑elephant conflict in the Sri Lankan dry zone: investigating social and geographical drivers through field‑based methods
(2023-07-02)
Human-elephant conflict (HEC) in Sri Lanka has escalated over the recent years, with, on average, 300 elephant deaths annually and human casualties of around 90 per year. Employing field-based qualitative methods, this contribution identifies causes and contexts of human-elephant conflict in those parts of the Sri Lankan dry zone most severely affected. We have used field observations as well as semi-structured interviews with experts and affected villagers as primary data collection techniques. The findings show ...
Aufsatz
A multiscale approach reveals elaborate circulatory system and intermittent heartbeat in velvet worms (Onychophora)
(2023-04-28)
An antagonistic hemolymph-muscular system is essential for soft-bodied invertebrates. Many ecdysozoans (molting animals) possess neither a heart nor a vascular or circulatory system, whereas most arthropods exhibit a well-developed circulatory system. How did this system evolve and how was it subsequently modified in panarthropod lineages? As the closest relatives of arthropods and tardigrades, onychophorans (velvet worms) represent a key group for addressing this question. We therefore analyzed the entire circulatory ...
Aufsatz
Review of the Psychodinae from Mallorca, Spain, with description of Pericoma unipennata, sp. n. (Diptera, Psychodidae)
(2016-04-05)
We review the Psychodinae of Mallorca, recognising fifteen species based on recent collections and available literature. Previously unpublished data is presented for eleven species, of which Neoarisemus ibericus Wagner, 1978, Mormia tenebricosa (Vaillant, 1954), Clogmia albipunctata (Williston, 1893), Lepiseodina rothschildi (Eaton, 1913), Paramormia ustulata (Walker, 1856), Philosepedon pyrenaicus Vaillant, 1974 and Psychoda (Psycha) grisescens Tonnoir, 1922 are first records for Mallorca. An old record of Pericoma ...
Aufsatz
Neither per, nor tim1, nor cry2 alone are essential components of the molecular circadian clockwork in the Madeira cockroach
(2020-08-04)
Circadian clocks control rhythms in physiology and behavior entrained to 24 h light–dark cycles. Despite of conserved general schemes, molecular circadian clockworks differ between insect species. With RNA interference (RNAi) we examined an ancient circadian clockwork in a basic insect, the hemimetabolous Madeira cockroach Rhyparobia maderae. With injections of double-stranded RNA (dsRNA) of cockroach period (Rm´per), timeless 1 (Rm´tim1), or cryptochrome 2 (Rm´cry2) we searched for essential components of the clock´s ...
Aufsatz
Wilde Urbaniten
(2020-04-24)
Die rechtlich-administrative und räumlich-planende Regulation des Vorkommens wildlebender Tiere im urbanen Raum lässt sich drei historisch gewachsenen Regimen zuordnen: Das Regime der Hygiene konstituiert die wilden Tiere der Stadt als Schädlinge, Lästlinge oder Nützlinge, das der Jagd als Nutzwild, Raubwild oder Raubzeug und das des Naturschutzes als Schutzobjekte, als heimisch oder fremd und als Leistungsträger oder Schädlinge. Dieses Regimedenken wandelt sich derzeit in der räumlichen Planungspraxis. Es wird mit ...