Spiders (Order Araneae) can be found in all continents, except Antarctica. This order has a long evolutionary history that began during the Paleozoic Era. Despite this prolonged span and the diversity of extant species, the fossil record of spiders is relatively modest, with most specimens preserved in amber and found in the Northern Hemisphere. Taubaracna maculosa nov. gen.
The origin of the air sac system present in birds has been an enigma for decades. Skeletal pneumaticity related to an air sac system is present in both derived non-avian dinosaurs and pterosaurs. But the question remained open whether this was a shared trait present in the common avemetatarsalian ancestor. We analyzed three taxa from the Late Triassic of South Brazil, which are some of the oldest representatives of this clade (233.23 ± 0.73 Ma), including two sauropodomorphs and one herrerasaurid.
Early Warning Systems (EWS) are non-structural measures for landslides disaster prevention. They are based on the detection of impending failure signals. The results of a landslide simulation experiment where accelerometers were used to identify pre-failure signals are presented in this paper. Landslide was simulated in a tilting flume filled with sandy soil. During the experiment, the flume was fixed at 30° inclination and water percolated through the soil until it slid.
The Borborema Province hosts several Mn-rich metasedimentary sequences, containing up to 40 wt% MnO(total). These sequences are composed of Mn oxide and Mn silicate lenses that alternate with spessartite quartzite layers. They are also spatially associated with graphite-bearing gneissic and granitic rocks.
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