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1. Composite modeling of leaf shape along shoots discriminates Vitis species better than individual leaves

   https://doi.org/10.1002/aps3.11404  

   Bryson, Abigail E. ; Wilson Brown, Maya ; Mullins, Joey ; Dong, Wei ; Bahmani, Keivan ; Bornowski, Nolan ; Chiu, Christina ; Engelgau, Philip ; Gettings, Bethany ; Gomezcano, Fabio ; et al ( December 2020 , Applications in Plant Sciences)

   Leaf morphology is dynamic, continuously deforming during leaf expansion and among leaves within a shoot. Here, we measured the leaf morphology of more than 200 grapevines (Vitisspp.) over four years and modeled changes in leaf shape along the shoot to determine whether a composite leaf shape comprising all the leaves from a single shoot can better capture the variation and predict species identity compared with individual leaves.

   Using homologous universal landmarks found in grapevine leaves, we modeled various morphological features as polynomial functions of leaf nodes. The resulting functions were used to reconstruct modeled leaf shapes across the shoots, generating composite leaves that comprehensively capture the spectrum of leaf morphologies present.

   We found that composite leaves are better predictors of species identity than individual leaves from the same plant. We were able to use composite leaves to predict the species identity of previously unassigned grapevines, which were verified with genotyping.

   Observations of individual leaf shape fail to capture the true diversity between species. Composite leaf shape—an assemblage of modeled leaf snapshots across the shoot—is a better representation of the dynamic and essential shapes of leaves, in addition to serving as a better predictor of species identity than individual leaves.

    

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2. A Holocene history of monkey puzzle tree (pehuén) in northernmost Patagonia

   https://doi.org/10.1111/jbi.14041  

   Nanavati, William ; Whitlock, Cathy ; Outes, Valeria ; Villarosa, Gustavo ( December 2020 , Journal of Biogeography)

   Although it is established that climate and fire have greatly influenced the long‐term ecosystem dynamics of Patagonia south of 40°S, the environmental history from northernmost Patagonia (37–40°S), where endemic and endangered monkey puzzle tree (Araucaria araucana) occurs, is poorly known. Here we ask: (a) What is the Holocene vegetation and fire history at the north‐eastern extent ofA. araucanaforest? (b) How have climate and humans influenced the past distribution ofA. araucana?

   Northernmost Patagonia, Argentina and Chile (37–40°S).

   Araucaria araucana,Nothofagus, Poaceae.

   Sedimentary pollen and charcoal from Laguna Portezuelo (37.9°S, 71.0°W; 1,730 m; 11,100 BP) were evaluated using statistical methods and compared with other palaeoecological, independent palaeoclimate, and historical records to assess how changes in climate and land use influenced local‐to‐regional environmental history.

   An open forest‐steppe landscape persisted at L. Portezuelo throughout the Holocene with generally low‐to‐moderate fire activity. IncreasedNothofaguspollen after ~6,590 BP suggests increases in shrubland and moisture in association with cooler conditions and greater seasonality and ENSO activity.Araucariapollen appeared at L. Portezuelo at ~6,380 BP, but was low in abundance until ~370 BP, when it rose with charcoal levels. This increase inAraucariaand fire coincided with a regional influx of Mapuche American Indians.Nothofagusdeforestation andPinussilviculture marked Euro‐American settlement beginning in the 19–20th century.

   (a) Rapid postglacial warming and drying limited the distribution ofAraucariain the central valley of Chile. In the middle and late Holocene, decreased temperatures and greater seasonality and ENSO activity increased precipitation variability allowingAraucariaexpansion at its north‐eastern limit. (b) Greater abundance ofAraucariaand heightened fire activity at L. Portezuelo after 370 BP coincided with increased Mapuche‐Pehuenche American Indian land use, suggesting thatAraucariamay have been managed in a human‐altered landscape.

    

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3. Paleobiology of a large mammal community from the late Pleistocene of Sonora, Mexico

   https://doi.org/10.1017/qua.2020.125  

   Short, Rachel A. ; Emmert, Laura G. ; Famoso, Nicholas A. ; Martin, Jeff M. ; Mead, Jim I. ; Swift, Sandy L. ; Baez, Arturo ( January 2021 , Quaternary Research)

   null (Ed.)

   A paleontological deposit near San Clemente de Térapa represents one of the very few Rancholabrean North American Land Mammal Age sites within Sonora, Mexico. During that time, grasslands were common, and the climate included cooler and drier summers and wetter winters than currently experienced in northern Mexico. Here, we demonstrate restructuring in the mammalian community associated with environmental change over the past 40,000 years at Térapa. The fossil community has a similar number of carnivores and herbivores whereas the modern community consists mostly of carnivores. There was also a 97% decrease in mean body size (from 289 kg to 9 kg) because of the loss of megafauna. We further provide an updated review of ungulates and carnivores, recognizing two distinct morphotypes of Equus, including E. scotti and a slighter species; as well as Platygonus compressus; Camelops hesternus; Canis dirus; and Lynx rufus; and the first regional records of Palaeolama mirifica, Procyon lotor, and Smilodon cf. S. fatalis. The Térapa mammals presented here provide a more comprehensive understanding of the faunal community restructuring that occurred in northern Mexico from the late Pleistocene to present day, indicating further potential biodiversity loss with continued warming and drying of the region. 

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4. The fungal ecology of the Brassington Formation (Middle Miocene) of Derbyshire, United Kingdom, and a new method for palaeoclimate reconstruction

   https://doi.org/10.3389/fevo.2022.947623  

   Pound, Matthew J. ; Nuñez Otaño, Noelia B. ; Romero, Ingrid C. ; Lim, Michael ; Riding, James B. ; O’Keefe, Jennifer M. ( August 2022 , Frontiers in Ecology and Evolution)

   Fossil fungi from periods warmer than modern climates provide unique insights into the future impacts of anthropogenic climate change. Here we report the fossil fungal assemblage from the late Middle Miocene Kenslow Member of central England, associated with climatic conditions warmer than the present-day. The identification of 110 morphotypes, which primarily relate to moist environments and the presence of wood, have been used to develop a new nearest living relative palaeoclimate reconstruction. The fungal assemblage indicates a Köppen–Geiger climate class, represented by temperate conditions, no dry season, and warm summers. This new fungal-based palaeoclimate reconstruction technique holds exciting potential to explore critically important but poorly understood palaeoenvironments, and the resulting qualitative inferences align well with previously published palaeobotanical quantitative estimates of palaeoclimate. These findings show that diverse fungal assemblages can successfully be used to reconstruct past climates for the first time. 

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5. Mandibular symphyseal fusion in fossil primates: Insights from correlated patterns of jaw shape and masticatory function in living primates

   https://doi.org/10.1002/ajpa.24048  

   Knigge, Ryan P. ; Vinyard, Christopher J. ; McNulty, Kieran P. ( March 2020 , American Journal of Physical Anthropology)

   Variation in primate masticatory form and function has been extensively researched through both morphological and experimental studies. As a result, symphyseal fusion in different primate clades has been linked to either the recruitment of vertically directed balancing‐side muscle force, the timing and recruitment of transversely directed forces, or both. This study investigates the relationship between jaw muscle activity patterns and morphology in extant primates to make inferences about masticatory function in extinct primates, with implications for understanding the evolution of symphyseal fusion.

   Three‐dimensional mandibular landmark data were collected for 31 extant primates and nine fossil anthropoids and subfossil lemur species. Published electromyography (EMG) data were available for nine of the extant primate species. Partial least squares analysis and phylogenetic partial least squares analysis were used to identify relationships between EMG and jaw shape data and evaluate variation in jaw morphology.

   Primates with partial and complete symphyseal fusion exhibit shape‐function patterns associated with the wishboning motor pattern and loading regime, in contrast to shape‐function patterns of primates with unfused jaws. All fossil primates examined (exceptApidium) exhibit jaw morphologies suggestive of the wishboning motor pattern demonstrated in living anthropoids and indriids.

   Partial fusion inCatopithecus, similar to indriids and some subfossil lemurs, may be sufficient to resist, or transfer, some amounts of transversely directed balancing‐side muscle force at the symphysis, representing a transition to greater reliance on transverse jaw movement during mastication. Furthermore, possible functional convergences in physiological patterns during chewing (i.e.,Archaeolemur) are identified.

    

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