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Army ants provide nourishment to a large variety of animals. This includes birds that feed on animals flushed out by army ant raids, symbiotic arthropods that consume the ants' prey or their brood, and other arthropods that scavenge on army ant refuse deposits. The latter have not received much attention, and the few published studies lack detailed species identifications. Here we provide a first systematic inventory of the beetle fauna associated with refuse deposits of Eciton army ants, with a focus on Eciton burchellii. We collected 8364 adult beetles, 511 larvae, and 24 eggs from 34 deposits at La Selva Biological Station, Costa Rica. We used a combination of DNA barcoding and morphology to identify a subset of 436 specimens to species level. The samples included several new species, and we here formally describe two water scavenger beetles (Hydrophilidae). Refuse deposits harbored a diverse beetle fauna. The identified subset consisted of 91 beetle species from 12 families, with rove beetles being the most abundant and diverse visitors. Of the 85 species found with E. burchellii, 50 species were collected from only one or two refuse deposits. Conversely, seven species were found in 10 or more refuse deposits, indicating a certain level of habitat specialization. We matched adults and immatures for 22 beetle species via DNA barcodes, demonstrating that army ant middens also serve as a beetle nursery. The present survey highlights the significant ecological function of army ants as promoters of biodiversity and their status as keystone species in tropical rainforests.

In nur einem Jahrhundert hat die Menschheit ihre Lebenserwartung und ihren Lebensstandard aktive deutlich erhöht. Zu dieser Entwicklung leisten zwei revolutionäre Entdeckungen einen wesentlichen Beitrag: die Entdeckung von antimikrobiellen Substanzen und deren industrielle Verarbeitung zu antibiotischen Medikamenten, und die Entwicklung von Polymerfasern, welche günstig, leicht, und langlebig sind. Plastik. Gleich welche Verbesserungen diese beiden Entdeckungen und Entwicklungen bringen, in der kurzen Zeit der Verfügbarkeit beider Produkte, Verwendung wir sie in derartigen Massen, dass sie unsere Umwelt und unsere Gesundheit über die Grenzen ihrer Nutzung hinaus bedrohen. Mikroplastik kann heute in der Tiefsee nachgewiesen werden, einem Orten dieser Welt, welcher von keinem Menschen je bereist wurde. Selbst in nur schwer erreichbaren terrestrischen Lebensräumen, hunderte Kilometer von den nächsten menschlichen Siedlungen entfernt, kann Mikroplastik gefunden werden. Das weltweit vermehrte auftreten multiresistenter Bakterien bedroht die globale öffentliche Gesundheit zunehmend, da es für solche Krankheitserreger keine spezifische Behandlung gibt. Immer mehr Studien haben in den letzten Jahren gezeigt, dass Mikroplastik die Verbreitung von Antibiotikaresistenzen fördert und als Vektor in vom Menschen weitgehend unberührte Habitate für ebendiese Resistenzen fungiert. Antibiotikaresistenzen wurde in der Kryosphäre bereits untersucht, jedoch liegt hier nach unserem Wissensstand die erste Studie vor, welche Mikroplastik und arktische bodenbewohnende Mikroorganismen in Bezug zu Antibiotikaresistenzen stellt. Die vorliegenden Ergebnisse zeigen keinen signifikanten Zusammenhang zwischen der Veränderung des Hemmhofdurchmessers und der Zugabe von Polymeren zum Wachstumsmedium der Bakterien. Der einzige ermittelbare Faktor, welcher einen signifikanten Einfluss auf den Hemmhof hatte, war die Zeit, wobei es mit zunehmender Zeit, entgegen der ursprünglichen Annahme, zu einer Zunah, Within just one century, humanity has managed to actively cause an increase in their life expectancy and in their living standards. Two revolutionary discoveries are playing a major role in these improvements: the discovery of antimicrobial substances and their industrial processing to antibiotic medications, and the development of polymer fabrics that are cheap, light, and long living. Plastics. Whatever improvements these two discoveries are bringing, within the time of their use, we have managed to overuse both substances to a level that is harming our environment and our health in a degree beyond the borders of their usage. Microplastics can be found at places on this planet where no human has ever touched a foot, the deep sea. Even in hard-to-reach terrestrial ecosystems, where humans are hundreds of kilometers away, microplastics can be detected. The occurrence of multi drug resistant bacteria is a major threat for public health, as there is no cure for infections with these pathogens, and it is a globally increasing threat. In the last years many studies have shown, that microplastic is having an impact on the dissemination of antibiotic resistances, which implicates that it might serve as a vector for those resistances to reach remote environments before humas do. Even though antibiotic resistances have been examined in the cryosphere, to our knowledge, this is the first study combining microplastics and arctic soil microbiota with respect to antibiotic resistances. The results of this study did not show significant relations between polymer addition to the bacteria´s growth medium and the change in inhibition zone diameter for all tested samples. The observed factor for changes in diameter was found to be time, with an increase in diameter of the inhibition zone over time and not a decrease as was suggested to happen. Using a cultivation-based approach, this study indicates that this method is suitable for antimicrobial susceptibility testing for arctic soi, Masterarbeit Universität Innsbruck 2023

Tropical rainforests are among the most diverse biomes on Earth. While species inventories are far from complete for any tropical rainforest, even less is known about the intricate species interactions that form the basis of these ecological communities. One fascinating but poorly studied example are the symbiotic associations between army ants and their rich assemblages of parasitic arthropod guests. Hundreds of these guests, or myrmecophiles, have been taxonomically described. However, because previous work has mainly been based on haphazard collections from disjunct populations, it remains challenging to define species boundaries. We therefore know little about the species richness, abundance and host specificity of most guests in any given population, which is crucial to understand co‐evolutionary and ecological dynamics. Here, we report a quantitative community survey of myrmecophiles parasitizing the six sympatric Eciton army ant species in a Costa Rican rainforest. Combining DNA barcoding with morphological identification of over 2,000 specimens, we discovered 62 species, including 49 beetles, 11 flies, one millipede and one silverfish. At least 14 of these species were new to science. Ecological network analysis revealed a clear signal of host partitioning, and each Eciton species was host to both specialists and generalists. These varying degrees in host specificities translated into a moderate level of network specificity, highlighting the system's level of biotic pluralism in terms of biodiversity and interaction diversity. By providing vouchered DNA barcodes for army ant guest species, this study provides a baseline for future work on co‐evolutionary and ecological dynamics in these species‐rich host-symbiont networks across the Neotropical realm.

SIGNIFICANCE B cell lymphoma-2 (Bcl-2) is the prototypical anti-apoptotic member of the Bcl-2 family that comprises proteins with contrasting effects on cell fate. Identified as a consequence chromosomal translocation (t 14:18) in human lymphoma, subsequent studies have revealed mutations and/or copy number alterations, as well as post-translational modifications, of Bcl-2 in a variety of cancers. The canonical function of Bcl-2 is linked to its ability to inhibit mitochondrial membrane permeabilization, regulating apoptosome assembly and activation by blocking cytosolic translocation of death amplification factors. RECENT ADVANCES Aside from maintaining mitochondrial integrity, a novel facet of Bcl-2 biology involves crosstalk with cellular redox state. Bcl-2 overexpression modulates mitochondrial redox metabolism to create a 'pro-oxidant' milieu, conducive for cell survival. Under oxidative stress, Bcl-2 functions as a redox sink to prevent excessive build-up of reactive oxygen species, inhibiting execution signals. Evidence indicates various redox-dependent transcriptional changes and post-translational modifications with different functional outcomes. CRITICAL ISSUES Understanding the complex interplay between Bcl-2 and the cellular redox milieu from the standpoint of cell fate signaling remains vital for understanding pathological states associated with altered redox metabolism and/or aberrant Bcl-2 expression. FUTURE DIRECTIONS Small molecule inhibitors of Bcl-2 are showing promise in the clinic. The non-canonical activity linked to cellular redox metabolism provides a novel avenue for the design and development of diagnostic and therapeutic strategies against cancers refractory to conventional chemotherapy.