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Songbirds have one special accessory chromosome, the so-called germline-restricted chromosome (GRC), which is only present in germline cells and absent from all somatic tissues. Earlier work on the zebra finch (Taeniopygia guttata castanotis) showed that the GRC is inherited only through the female line-like the mitochondria-and is eliminated from the sperm during spermatogenesis. Here, we show that the GRC has the potential to be paternally inherited. Confocal microscopy using GRC-specific fluorescent in situ hybridization probes indicated that a considerable fraction of sperm heads (1 to 19%) in zebra finch ejaculates still contained the GRC. In line with these cytogenetic data, sequencing of ejaculates revealed that individual males from two families differed strongly and consistently in the number of GRCs in their ejaculates. Examining a captive-bred male hybrid of the two zebra finch subspecies (T. g. guttata and T. g. castanotis) revealed that the mitochondria originated from a castanotis mother, whereas the GRC came from a guttata father. Moreover, analyzing GRC haplotypes across nine castanotis matrilines, estimated to have diverged for up to 250,000 y, showed surprisingly little variability among GRCs. This suggests that a single GRC haplotype has spread relatively recently across all examined matrilines. A few diagnostic GRC mutations that arose since this inferred spreading suggest that the GRC has continued to jump across matriline boundaries. Our findings raise the possibility that certain GRC haplotypes could selfishly spread through the population via occasional paternal transmission, thereby out-competing other GRC haplotypes that were limited to strict maternal inheritance, even if this was partly detrimental to organismal fitness.

Geothermal Energy is regarded an important element of many future scenarios of 100% renewable energy. Besides biomass, hydrodams and wave plants, geothermal can provide a steady base load of energy. While the technology received little attention compared to wind or solar for most of its history, this has significantly changed in Germany in recent years. Since an earthquake attributed to geothermal development in Swiss Basel in 2006, a risk discourse evolved in German language media reports. Subsequently local protest groups have been founded that establish a new environmental protest movement. According to the theory of vested interests (Kousis, 1993; Schnaiberg, 1993) and socially constructed risk perceptions (Douglas and Wildavsky, 1982) the future development of deep geothermal technologies will continue to be accompanied by strong conflicts of acceptance, that are likely to slow down its dissemination significantly.

Copper has above-average significance as technology metal due to its diverse use in various important branches of industry and its relevance in terms of quantity. The collection of waste made of metallic copper and copper alloys, and recycling the material collected has always been a common practice in copper processing. One way of increasing raw material efficiency is to recover raw materials from low-value waste. The recovery of copper from copper-containing residual materials through cementation with low-quality aluminium waste was tested successfully and developed sufficiently for a pilot plant on technical scale to be designed and calculated. The framework conditions of the process developed unfavourably during the course of the project. With the quantity of copper-containing residual materials currently available, economic operation of a large-scale industrial cementation plant is no longer feasible. It is uncertain whether, under current market conditions, it would be possible to acquire the residual material quantities required for economic operation at justifiable prices or with additional payment. Under these boundary conditions, the entrepreneurial risk is currently so high that investment in a cementation plant was put on hold, at least for the time being., Copper has above-average significance as technology metal due to its diverse use in various important branches of industry and its relevance in terms of quantity. The collection of waste made of metallic copper and copper alloys, and recycling the material collected has always been a common practice in copper processing. One way of increasing raw material efficiency is to recover raw materials from low-value waste. The recovery of copper from copper-containing residual materials through cementation with low-quality aluminium waste was tested successfully and developed sufficiently for a pilot plant on technical scale to be designed and calculated. The framework conditions of the process developed unfavourably during the course of the project. With the quantity of copper-containing residual materials currently available, economic operation of a large-scale industrial cementation plant is no longer feasible. It is uncertain whether, under current market conditions, it would be possible to acquire the residual material quantities required for economic operation at justifiable prices or with additional payment. Under these boundary conditions, the entrepreneurial risk is currently so high that investment in a cementation plant was put on hold, at least for the time being.