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Sharks have a reputation as ravenous hunters and apex predators, but new analysis of fossil records shows that some of the earliest sharks might have been filter feeders, taking in water through their...
Fossil deep-sea selachians are rare and their diversity underestimated as a consequence of the scarcity of available outcrops of sediments containing them. Here we report a new fossil locality from th...
The early history of heterodontid sharks is documented mainly by isolated teeth. So far, three different heterodontid genera have been recorded from the Jurassic: Proheterodontus from theMiddle Jurass...
As many hybodont sharks are known solely from their teeth, this investigation approaches the phylogeny of the group with an emphasis on tooth morphology and dentitional patterns. The preliminary resul...
The affinities of the selachian genus Ptychodus is discussed and Hemiptychodus is here re-introduced as a subgenus characterized by unusual tooth ornamentation pattern.An overview ofAsian hybodont gen...
Two limestone bone-beds in the early Frasnian of the Chahriseh section, central Iran, yielded numerous chondrichthyan teeth and scales. The fauna includes, most probably, only two taxa: a hitherto unk...
Devonian filter-feeding sharks     Chondrichthyes  Teeth  Devonian  Frasnian  Utah  Nevada       2009/10/20
Upper Frasnian rocks of Utah and Nevada yielded several multicuspid, low-crowned shark teeth. It is proposed that they were used mainly for filtering food from water. Two new chondrichthyan species be...
Bieńkowska-wasiluk, M. and radwański, A. 2009. A new occurrence of sharks in the Menilite Formation (Lower Oligocene) from the Outer (Flysch) Carpathians of Poland. Acta Geologica Polonica, 59 (2), 23...

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