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1. Evolutionary genomics of oceanic island radiations

   https://doi.org/10.1016/j.tree.2023.02.003  

   Cerca, José; Cotoras, Darko D.; Bieker, Vanessa C.; De-Kayne, Rishi; Vargas, Pablo; Fernández-Mazuecos, Mario; López-Delgado, Julia; White, Oliver; Stervander, Martin; Geneva, Anthony J.; et al (July 2023, Trends in Ecology & Evolution)
2. Island-wide characterization of agricultural production challenges the demographic collapse hypothesis for Rapa Nui (Easter Island)

   https://doi.org/10.1126/sciadv.ado1459  

   Davis, Dylan S; DiNapoli, Robert J; Pakarati, Gina; Hunt, Terry L; Lipo, Carl P (June 2024, Science Advances)

   Communities in resource-poor areas face health, food production, sustainability, and overall survival challenges. Consequently, they are commonly featured in global debates surrounding societal collapse. Rapa Nui (Easter Island) is often used as an example of how overexploitation of limited resources resulted in a catastrophic population collapse. A vital component of this narrative is that the rapid rise and fall of pre-contact Rapanui population growth rates was driven by the construction and overexploitation of once extensive rock gardens. However, the extent of island-wide rock gardening, while key for understanding food systems and demography, must be better understood. Here, we use shortwave infrared (SWIR) satellite imagery and machine learning to generate an island-wide estimate of rock gardening and reevaluate previous population size models for Rapa Nui. We show that the extent of this agricultural infrastructure is substantially less than previously claimed and likely could not have supported the large population sizes that have been assumed 

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3. Geological insights from the newly discovered granite of Sif Island between Thwaites and Pine Island glaciers

   https://doi.org/10.1017/S0954102023000287  

   Marschalek, James W.; Thomson, Stuart N.; Hillenbrand, Claus-Dieter; Vermeesch, Pieter; Siddoway, Christine; Carter, Andrew; Nichols, Keir; Rood, Dylan H.; Venturelli, Ryan A.; Hammond, Samantha J.; et al (February 2024, Antarctic Science)

   Large-scale geological structures have controlled the long-term development of the bed and thus the flow of the West Antarctic Ice Sheet (WAIS). However, complete ice cover has obscured the age and exact positions of faults and geological boundaries beneath Thwaites Glacier and Pine Island Glacier, two major WAIS outlets in the Amundsen Sea sector. Here, we characterize the only rock outcrop between these two glaciers, which was exposed by the retreat of slow-flowing coastal ice in the early 2010s to form the new Sif Island. The island comprises granite, zircon U-Pb dated to ~177–174 Ma and characterized by initial ɛ_Nd,⁸⁷Sr/⁸⁶Sr and ɛ_Hfisotope compositions of -2.3, 0.7061 and -1.3, respectively. These characteristics resemble Thurston Island/Antarctic Peninsula crustal block rocks, strongly suggesting that the Sif Island granite belongs to this province and placing the crustal block's boundary with the Marie Byrd Land province under Thwaites Glacier or its eastern shear margin. Low-temperature thermochronological data reveal that the granite underwent rapid cooling following emplacement, rapidly cooled again at ~100–90 Ma and then remained close to the Earth's surface until present. These data help date vertical displacement across the major tectonic structure beneath Pine Island Glacier to the Late Cretaceous. 

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4. Mycorrhizal types influence island biogeography of plants

   https://doi.org/10.1038/s42003-021-02649-2  

   Delavaux, Camille S.; Weigelt, Patrick; Dawson, Wayne; Essl, Franz; van Kleunen, Mark; König, Christian; Pergl, Jan; Pyšek, Petr; Stein, Anke; Winter, Marten; et al (December 2021, Communications Biology)

   Abstract Plant colonization of islands may be limited by the availability of symbionts, particularly arbuscular mycorrhizal (AM) fungi, which have limited dispersal ability compared to ectomycorrhizal and ericoid (EEM) as well as orchid mycorrhizal (ORC) fungi. We tested for such differential island colonization within contemporary angiosperm floras worldwide. We found evidence that AM plants experience a stronger mycorrhizal filter than other mycorrhizal or non-mycorrhizal (NM) plant species, with decreased proportions of native AM plant species on islands relative to mainlands. This effect intensified with island isolation, particularly for non-endemic plant species. The proportion of endemic AM plant species increased with island isolation, consistent with diversification filling niches left open by the mycorrhizal filter. We further found evidence of humans overcoming the initial mycorrhizal filter. Naturalized floras showed higher proportions of AM plant species than native floras, a pattern that increased with increasing isolation and land-use intensity. This work provides evidence that mycorrhizal fungal symbionts shape plant colonization of islands and subsequent diversification. 

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5. A sensitivity analysis of barrier island breaching

   https://doi.org/10.1142/9789811275135_0224  

   Beever, M. (January 2023, Coastal Sediments 2023)

   This paper will discuss the beginnings of a sensitivity analysis of barrier island breaching. The study area of Mantoloking, New Jersey, USA is used as the barrier island breached significantly during Hurricane Sandy in 2012. The numerical model XBeach is used to conduct this study. The study investigates the affects that back-bay currents, water-level timing, and barrier-island configuration have on barrier island breaching. 

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