ScienceDaily: Plants & Animals News

A novel chip automates the reaction cascades occurring between molecules inside DNA to carry out complex mathematical calculations.

Plants respond to mild nitrogen deficiency by elongating their lateral roots. In this way, more nitrogen can be absorbed than before. Researchers have now discovered a hormonal regulatory module that mediates the molecular processes of this adaptation. Brassinosteroids and auxins play a central role in this.

In times of exacerbating biodiversity loss, reliable data on species occurrence are essential. Environmental DNA (eDNA) - DNA released from organisms into the water - is increasingly used to detect fishes in biodiversity monitoring campaigns. However, eDNA turns out to be capable of providing much more than fish occurrence data, including information on other vertebrates. A study demonstrates how comprehensively vertebrate diversity can be assessed at no additional costs.

Usually, the individuals of a population of marine species that have the potential to disperse over long distances all share a similar genetic composition. Yet every now and then, at small, localized sites, small groups of genetically different individuals suddenly appear within populations for a short period of time. A new study explains how this chaotic formation of genetic islands can occur in marine molluscs.

A new, location-specific agricultural greenhouse gas emission study is the first to account for net carbon dioxide, methane and nitrous oxide emissions from all subsectors related to food production and consumption. The work could help identify the primary plant- and animal-based food sectors contributing to three major greenhouse gas emissions and allow policymakers to take action to reduce emissions from the top-emitting food commodities at different locations across the globe.

A decades-long study of introduced voles on the Norwegian islands of Svalbard is helping to answer a longstanding puzzle of Arctic ecology -- what drives the well-established population cycles of small Arctic mammals, such as voles and lemmings. These plant-eating rodents are among the most populous Arctic mammals. The results suggest the importance of predators as a primary factor driving the cycles, and shows that bottom-up, herbivore-plant interactions fail to generate their usual population cycles.

CD8+ T cells -- known as "killer" T cells -- are the assassins of the immune system. Once they are primed, they seek out and destroy other cells that are infected with virus or cells that are cancerous. Priming involves dendritic cells -- sentinels of the immune system. In an influenza infection in the lungs, for example, lung-migratory dendritic cells capture a piece of the viral antigen, and then migrate out of the lung to the place where naïve T cells reside, to present that antigen to the CD8+ T cells. This primes the T cells to know which cells to attack. The place for the priming in influenza had long been thought to be restricted to a single anatomical site -- the lung-draining, mediastinal lymph nodes that lie between the lungs and the spine. This lymph node-centric paradigm now has been challenged.

Large carnivore populations are expanding across Europe and experts are calling for increased support for communities to encourage harmonious relationships with their new neighbors.

Scientists report a vampire fish attached to the body of an Amazonian thorny catfish. Very unusually, the candirus were attached close to the lateral bone plates, rather than the gills, where they are normally found. Since the hosts were not badly harmed, and the candirus apparently derived no food benefit, scientists believe this association is commensalistic rather than parasitic.