Magnetotactic bacteria have been the only known magnetoreceptive microorganisms for decades.Even if the existence of magnetotactic protists was suggested in 1986,this is only 30 years later that magnetotaxis was extended to the domain of Eukaryota,thanks to the characterization of magnetotactic symbiotic assemblies composed of a flagellated protist and bacteria biomineralizing magnetic crystals.Their mutualistic ectosymbiosis relies on a collective magnetotaxis coupled to a hydrogen-based syntrophy.This new form of cooperation challenges our view of magnetic biomineralization in prokaryotes and magnetoreception in eukaryotes.In this review,we present how magnetosymbiosis was discovered and how cooperation functions.Finally,we discuss the future research and the new perspectives such discovery brought to the field of magnetotaxis.
A uniquely shaped impact structure,the Hailin impact crater,has been discovered in northeast China.The crater was formed on a granodiorite hillside and is an oval depression with asymmetric rim height and a maximum diameter of 1360 m.The bottom of the crater is filled by Quaternary sediments with large amounts of rock fragments underneath.The discovery of quartz planar deformation features in rock clasts on the crater floor provides diagnostic evidence for the impact origin of the structure.The shape of the crater is largely due to the impact having occurred on a ridge terrain.The impact event probably occurred in the late Cenozoic Era.The Hailin impact crater is the fourth confirmed Chinese impact crater.
Stegolophodon is an age-informative genus of mammals that had a widespread distribution during the Neogene.This paper reports the discovery of Stegolophodon fossils from the Middle Miocene lower Fotan Formation at the Zhangpu locality,Fujian Province,China.This discovery represents the first evidence of Neogene proboscidean fossils in southeastern China.The newly found molar materials have low tooth crowns,very straight lophs/lophids,and an indistinct median sulcus.The mesoconelets and posterior cingulum are well-developed,while the second posterior pretrite central conule is significantly reduced.These specimens closely resemble Stegolophodon pseudolatidens in cheek tooth morphology,and can thus be attributed to the same species.This discovery fills a gap in the fossil record of large mammals in this region during the Neogene and provides valuable insights into the evolution of proboscideans and paleoenvironments.
