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Smithsonian Libraries and Archives Annual Report 2024
(2025) Smithsonian Libraries and Archives
Phylogeny, biogeography, reticulation, and classification of Agrostis (Poaceae: Pooideae: Poeae: Agrostidinae) with expansion of Polypogon to include Lachnagrostis (in part)
(2025) Peterson, Paul M.; Soreng, Robert J.; Romaschenko, Konstantin; Barberá, Patricia; Quintanar, Alejandro; Aedo, Carlos; Saarela, Jeffery M.
To investigate the evolutionary relationships and biogeographical history among the species of Agrostis and allied genera within the subtribe Agrostidinae, we generated a phylogeny based on sequences from nuclear ribosomal DNA (ITS) and three plastid regions ( rpl32‐trnL spacer, rps16‐trnK spacer, and rps16 intron). We also aimed to assess the generic limits of Agrostis , characterize possible subgeneric relationships among species in the genus, identify hypothesized reticulation events, and present our biogeographical theory. Based on our phylogeny of 198 samples, representing 138 species (82 from Agrostis as currently recognized, 10 from Polypogon , and 10 from Lachnagrostis ), we identify two strongly supported clades within Agrostis : clade Longipaleata ( Agrostis subg. Vilfa ) and clade Brevipaleata ( A . subg. Agrostis ). The species of Agrostis in clade Longipaleata usually have florets with paleas 2/5 to as long as the lemma, whereas species in clade Brevipaleata have florets with paleas less than 2/5 as long as the lemma, minute, or absent. Core (species with congruent alignment using ITS and plastid data) phylogenetic analysis of Agrostis reveals three strongly supported clades within Longipaleata (European‐Northwest African, Asian, and African), three strongly supported clades within Brevipaleata (Asian, North American, and South American), and a European grade leading to the latter two. Of the six genera commonly associated with Agrostis , that is, Bromidium , Polypogon, Lachnagrostis, Linkagrostis, Chaetopogon, and Chaetotropis , only Polypogon maintained its status as a separate genus, while the remaining genera are subsumed within Agrostis or Polypogon . Polypogon is identified as an intergeneric hybrid originating via ancient hybridization between unknown representatives of Agrostis clade Longipaleata (plastid DNA) and Calamagrostis clade Americana (nrDNA). We include several species of Lachnagrostis , including the type ( L. filiformis ), that follow the same pattern in Polypogon , while the remaining species of Lachnagrostis in our study are identified as ancient intersubgeneric hybrids within Agrostis . We propose nine new combinations in Polypogon : P. adamsonii (Vickery) P.M. Peterson, Soreng & Romasch.; P. aemulus (R. Br.) P.M. Peterson, Soreng & Romasch.; P. billardierei (R. Br.) P.M. Peterson, Soreng & Romasch.; P. bourgaei (E. Fourn.) P.M. Peterson, Soreng & Romasch.; P. filiformis (G. Forst.) P.M. Peterson, Soreng & Romasch.; P. littoralis P.M. Peterson, Soreng & Romasch.; P. exaratus (Trin.) P.M. Peterson, Soreng & Romasch.; P. polypogonoides (Stapf) P.M. Peterson, Soreng & Romasch.; and P. reuteri (Boiss.) P.M. Peterson, Soreng & Romasch. We designate lectotypes for the names Agrostis sect. Aristatae Willd., Agrostis barbuligera Stapf, A. bourgaei E. Fourn., A. eriantha Hack., A. exarata Trin., A. lachnantha Nees, A. polypogonoides Stapf, Chaetotropis chilensis Kunth, Polypogon elongatus Kunth, P. inaequalis Trin., P. suspicatus Willd., and Vilfa muricata J. Presl .
The axillary lymphoid organ is an external, experimentally accessible immune organ in the zebrafish
(2025) Castranova, Daniel; Kenton, Madeleine I.; Kraus, Aurora; Dell, Christopher W.; Park, Jong S.; Venero Galanternik, Marina; Park, Gilseung; Lumbantobing, Daniel N.; Dye, Louis; Marvel, Miranda; Iben, James; Taimatsu, Kiyohito; Pham, Van; Willms, Reegan J.; Blevens, Lucas; Robertson, Tanner F.; Hou, Yiran; Huttenlocher, Anna; Foley, Edan; Parenti, Lynne R.; Frazer, J. K.; Narayan, Kedar; Weinstein, Brant M.
Lymph nodes and other secondary lymphoid organs play critical roles in immune surveillance and immune activation in mammals, but the deep internal locations of these organs make it challenging to image and study them in living animals. Here, we describe a previously uncharacterized external immune organ in the zebrafish ideally suited for studying immune cell dynamics in vivo, the axillary lymphoid organ (ALO). This small, translucent organ has an outer cortex teeming with immune cells, an inner medulla with a mesh-like network of fibroblastic reticular cells along which immune cells migrate, and a network of lymphatic vessels draining to a large adjacent lymph sac. Noninvasive high-resolution imaging of transgenically marked immune cells can be carried out in ALOs of living animals, which are readily accessible to external treatment. This newly discovered tissue provides a superb model for dynamic live imaging of immune cells and their interaction with pathogens and surrounding tissues, including blood and lymphatic vessels.
Independent lines of evidence document the identification of bird–aircraft collision sample of Western Marsh Harrier (Circus aeruginosus) in continental USA
(2025) Dove, Carla J.; Bevier, Louis R.; Luttrell, Sarah A. M.; Whatton, James F.; Dahlan, Faridah; Andrews,Frank, III
Bird–aircraft collisions (birdstrikes) occur daily and are global in scale. In the USA, the Federal Aviation Administration (FAA) tracks information regarding birdstrikes in the National Wildlife Strike Database to improve aviation safety. Here, we describe the use of independent lines of evidence for final species identification of an unusual birdstrike sample submitted for identification from Newark Liberty International Airport, New Jersey, in November 2022. Using DNA barcoding, molecular sexing, feather pattern matching, feather ultrastructure, and online community science reports, we surmise that the birdstrike sample originated from the same individual Western Marsh Harrier (Circus aeruginosus) that was photographed and reported to eBird at a location proximate to where the birdstrike occurred. The identification of this sample suggests an unusual end to a rare bird in the USA with the feather sample representing the first specimen record (USNM 665437) of Western Marsh Harrier in the continental United States. This case study underscores the importance of linking independent lines of evidence to confirm complex bird identifications, help document bird records, and track unusual bird movements.
Dispersal and Paleoecology of Tropical Podocarps
(Smithsonian Institution Scholarly Press, 2011) Morley, Robert J.; Turner, Benjamin L. ; Cernusak, Lucas A.