Freshwater sponges (Porifera: Spongillida) are sessile invertebrates with skeletons composed of siliceous elements termed spicules. Sponge spicules (megascleres, microscleres, and gemmuloscleres) characterized by widely varying sizes shapes. These well-preserved in lacustrine, wetland, riverine sediments hold significant ecological limnological information that can be applied as diagnostic tool...

From approximately 11,200 to 8,000 years ago, the Great Plains of North America were populated by small Paleoindian hunting groups with well developed weaponry and the expertise to successfully hunt large mammals, especially mammoths and bison. Mammoths became extinct on the Plains by 11,000 years ago, and, although paleoecological conditions were worsening, their demise may have been hastened ...

a Laboratory of Wetland Ecology and Monitoring, Faculty of Geographical and Geological Sciences, Adam Mickiewicz University, Dzięgielowa 27, 61-680 Poznań, Poland b Department of Biogeography and Paleoecology, Adam Mickiewicz University, Dzięgielowa 27, 61-680 Poznań, Poland c Faculty of Biology, Adam Mickiewicz University, Umultowska 89, 61-614 Poznań, Poland d Institute of Geological Sciences...