The Apalachicola River delta in Florida is where the river flows into the Gulf of Mexico. As the river reaches the gulf, it forms smaller channels where sediments carried by the river are deposited and form many deltaic lobes, or wetland formations. The shape and size of the delta are _____ by the gulf’s tides, which shift sediments along the coast and reshape the deltaic lobes over time.

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Lisa Linn Kanae is a celebrated contemporary Hawaiian author whose work is _____ by a rich literary history. From the traditional stories of the Kanaka Maoli, or Native Hawaiian people, to the works of writers such as David Malo, the literary heritage of Hawai‘i is distinctive and vibrant.

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Archaeologists have identified a plethora of beads fashioned from Tritia gibbosula shells in many Middle Stone Age (MSA) sites across western North Africa, including El Mnasra Cave, Morocco. In a 2021 paper, El Mehdi Sehasseh et al. attribute these artifacts' ___ to the evolution and propagation of symbolic behavior (e.g., use of personal ornaments) in humans and the availability of T. gibbosula during the MSA.

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Svante Pääbo and other researchers studying the history of organisms have long utilized ancient DNA—DNA recovered from ancient organic material that has been preserved under natural conditions. However, Reyjane P. Oliveira and colleagues’ 2017 study of the evolutionary trajectory of the Malagasy grass genus Chasechloa instead relied on historical DNA—genomic data incidentally preserved in specimens that are housed in natural history collections—thus capitalizing on the research potential offered by a vast but hitherto relatively underutilized source of insight into the biological past.

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Established knowledge of prehistoric societies primarily stems from analysis of durable historical artifacts, including stone tools, but Mercedes Murillo-Barroso and team have contributed new insights with a unique analysis of plant-based items. Plant-based artifacts, including straw baskets, are seldom studied due to their perishable nature. This relative scarcity made it all the more exciting when the team examined remains of well-preserved organic artifacts discovered in a cave in Spain and determined that they dated even further back than previously thought.

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