[ad_1] Opus incertum was a Roman masonry technique using small, irregularly shaped stones set in concrete walls. It was used in the 1st and 2nd century BC and gradually replaced by opus reticulatum. The technique is used to date archaeological finds and was described by Marcus Vitruvius Pollio in his book “Ten Books on Architecture.” […]
[ad_1] “Incertae sedis” is a term used in biology to describe a taxonomic group that is difficult to classify, often due to recent discovery, taxonomic challenges, or incomplete fossils. Molecular phylogeny has made classification easier, but many animals remain unclassified. Basal taxa are sometimes placed in a clade without a specific classification. The Ediacaran fauna […]