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In light of recent alarming trends in human population growth, climate change, and other environmental modifications, a "Warning to humanity" manifesto was published in BioScience in 2017. This call reiterated most of the ideas originally expressed by the Union of Concerned Scientists in 1992, including the fear that we are "pushing Earth's ecosystems beyond their capacities to support the web of life." As subterranean biologists, we take this opportunity to emphasize the global importance and the conservation challenges associated with subterranean ecosystems. They likely represent the most widespread nonmarine environments on Earth, but specialized subterranean organisms remain among the least documented and studied. Largely overlooked in conservation policies, subterranean habitats play a critical role in the function of the web of life and provide important ecosystem services. We highlight the main threats to subterranean ecosystems and propose a set of effective actions to protect this globally important natural heritage. [ABSTRACT FROM AUTHOR]

Although satellite DNAs arewell-explored components of heterochromatin and centromeres, little is known about emergence, dispersal and possible impact of comparably structured tandem repeats (TRs) on the genome-wide scale. Our bioinformatics analysis of assembled Tribolium castaneum genome disclosed significant contribution of TRs in euchromatic chromosomal arms and clear predominance of satellite DNA-typical 170 bp monomers in arrays of ≥5 repeats. By applying different experimental approaches, we revealed that the nine most prominent TR families Cast1-Cast9 extracted from the assembly comprise ~4.3% of the entire genome and reside almost exclusively in euchromatic regions. Among them, seven families that build ~3.9% of the genome are based on ~170 and ~340 bp long monomers. Results of phylogenetic analyses of 2500 monomers originating from these families show high-sequence dynamics, evident by extensive exchanges between arrays on non-homologous chromosomes. In addition, our analysis shows that concerted evolution acts more efficiently on longer than on shorter arrays. Efficient genome-wide distribution of nine TR families implies the role of transposition only in expansion of the most dispersed family, and involvement of other mechanisms is anticipated. Despite similarities in sequence features, FISH experiments indicate high-level compartmentalization of centromeric and euchromatic tandem repeats. [ABSTRACT FROM AUTHOR]