SwePub
Tyck till om SwePub Sök här!
Sök i SwePub databas

  Extended search

Träfflista för sökning "WFRF:(Johansson J) ;lar1:(nrm)"

Search: WFRF:(Johansson J) > Swedish Museum of Natural History

  • Result 1-10 of 19
Sort/group result
   
EnumerationReferenceCoverFind
1.
  • Bachmann, L., et al. (author)
  • The role of systematics for understanding ecosystem functions: Proceedings of the Zoologica Scripta Symposium, Oslo, Norway, 25 August 2022
  • 2023
  • In: Zoologica Scripta. - : Wiley. - 0300-3256 .- 1463-6409. ; 52:3, s. 187-214
  • Journal article (peer-reviewed)abstract
    • On 25 August 2022, the Zoologica Scripta - An International Journal of Systematic Zoology and the Norwegian Academy of Sciences and Letters arranged a symposium entitled 'The role of systematics for understanding ecosystem functions' in the Academy's premises in Oslo, Norway. The symposium aimed at offering a forum for exploring and discussing trends and future developments in the field of systematics. Eleven international experts contributed expertise on various issues related to global challenges, such as biodiversity assessments, databases, cutting-edge analysis tools, and the consequences of the taxonomic impediment. Here, we compiled a multi-author proceedings paper of the symposium contributions that are arranged in chapters and presents the content and the key conclusions of the majority of the presentations.
  •  
2.
  • Johansson, Åke, et al. (author)
  • A geochronological review of magmatism along the external margin of Columbia and in the Grenville-age orogens forming the core of Rodinia
  • 2022
  • In: Precambrian Research. - : Elsevier BV. - 0301-9268 .- 1872-7433. ; 371, s. 1-43
  • Journal article (peer-reviewed)abstract
    • A total of 4344 magmatic U-Pb ages in the range 2300 to 800 Ma have been compiled from the Great Proterozoic Accretionary Orogen along the margin of the Columbia / Nuna supercontinent and from the subsequent Grenvillian collisional orogens forming the core of Rodinia. The age data are derived from Laurentia (North America and Greenland, n = 1212), Baltica (NE Europe, n = 1922), Amazonia (central South America, n = 625), Kalahari (southern Africa and Dronning Maud Land in East Antarctica, n = 386), and western Australia (n = 199). Laurentia, Baltica, and Amazonia (and possibly other cratons) most likely formed a ca. 10 000-km-long external active continental margin of Columbia from its assembly at ca. 1800 Ma until its dispersal at ca. 1260 Ma, after which all cratons studied were involved in the Rodinia-forming Grenvillian orogeny. However, the magmatic record is not smooth and even but highly irregular, with marked peaks and troughs, both for individual cratons and the combined data set. Magmatic peaks typically range in duration from a few tens of million years up to around hundred million years, with intervening troughs of comparable length. Some magmatic peaks are observed on multiple cratons, either by coincidence or because of paleogeographic proximity and common tectonic setting, while others are not. The best overall correlation, 0.617, is observed between Baltica and Amazonia, consistent with (but not definitive proof of) their being close neighbours in a SAMBA-like configuration at least in Columbia, and perhaps having shared the same peri-Columbian subduction system for a considerable time. Correlation factors between Laurentia and Baltica, or Laurentia and Amazonia, are below 0.14. Comparison between the Grenville Province in northeastern Laurentia and the Sveconorwegian Province in southwestern Fennoscandia (Baltica) shows some striking similarities, especially in the Mesoproterozoic, but also exhibits differences in the timing of events, especially during the final Grenville-Sveconorwegian collision, when the Sveconorwegian evolution seems to lag behind by some tens of million years. Between the other cratons, the evolution before and during the final Grenvillian collision is also largely diachronous. After 900 Ma, magmatic activity had ceased in all areas investigated, attesting to the position of most of them within the stable interior of Rodinia. 
  •  
3.
  • Black, Andrew B., et al. (author)
  • Provisional identification of historical grasswren(Amytornis: Maluridae) specimens in European collectionsdraws attention to the incomplete phylogeny of the group
  • 2019
  • In: Bulletin of the British Ornithologists' Club. - : British Ornithologists' Club. - 0007-1595. ; 139:3, s. 228-237
  • Journal article (peer-reviewed)abstract
    • The phylogeny and systematics of grasswrens Amytornis species areincompletely resolved, in particular for three widely distributed members ofthe genus. In part this is a consequence of the dispersal to European and NorthAmerican collections of early specimens of now extinct populations. We describethree historical grasswren specimens from museums in Berlin and Stockholm, all ofwhich represent taxa for which phylogenetic and / or other data are incomplete. Wefurther identify other specimens that might contribute towards greater resolutionof grasswren phylogeny.
  •  
4.
  • Cappellini, Enrico, et al. (author)
  • Resolution of the type material of the Asian elephant, Elephas maximus Linnaeus, 1758 (Proboscidea, Elephantidae)
  • 2014
  • In: Zoological Journal of the Linnean Society. - : Oxford University Press (OUP). - 0024-4082 .- 1096-3642. ; 170:1, s. 222-232
  • Journal article (peer-reviewed)abstract
    • The understanding of Earth's biodiversity depends critically on the accurate identification and nomenclature of species. Many species were described centuries ago, and in a surprising number of cases their nomenclature or type material remain unclear or inconsistent. A prime example is provided by Elephas maximus, one of the most iconic and well-known mammalian species, described and named by Linnaeus (1758) and today designating the Asian elephant. We used morphological, ancient DNA (aDNA), and high-throughput ancient proteomic analyses to demonstrate that a widely discussed syntype specimen of E.maximus, a complete foetus preserved in ethanol, is actually an African elephant, genus Loxodonta. We further discovered that an additional E.maximus syntype, mentioned in a description by John Ray (1693) cited by Linnaeus, has been preserved as an almost complete skeleton at the Natural History Museum of the University of Florence. Having confirmed its identity as an Asian elephant through both morphological and ancient DNA analyses, we designate this specimen as the lectotype of E.maximus. The mass spectrometry proteomics data have been deposited in the ProteomeXchange Consortium with the data set identifier PXD000423.
  •  
5.
  •  
6.
  • Ericson, Per G P, 1956-, et al. (author)
  • Diversification of Neoaves : integration of molecular sequence data and fossils.
  • 2006
  • In: Biology Letters. - : The Royal Society. - 1744-9561 .- 1744-957X. ; 2:4, s. 543-7
  • Journal article (peer-reviewed)abstract
    • Patterns of diversification and timing of evolution within Neoaves, which includes almost 95% of all bird species, are virtually unknown. On the other hand, molecular data consistently indicate a Cretaceous origin of many neoavian lineages and the fossil record seems to support an Early Tertiary diversification. Here, we present the first well-resolved molecular phylogeny for Neoaves, together with divergence time estimates calibrated with a large number of stratigraphically and phylogenetically well-documented fossils. Our study defines several well-supported clades within Neoaves. The calibration results suggest that Neoaves, after an initial split from Galloanseres in Mid-Cretaceous, diversified around or soon after the K/T boundary. Our results thus do not contradict palaeontological data and show that there is no solid molecular evidence for an extensive pre-Tertiary radiation of Neoaves.
  •  
7.
  •  
8.
  •  
9.
  •  
10.
  • Irestedt, Martin, et al. (author)
  • Phylogeny of major lineages of suboscines (Passeriformes) analysed by nuclear DNA sequence data
  • 2001
  • In: Journal of Avian Biology. - : Blackwell. - 0908-8857 .- 1600-048X. ; 32:1, s. 15-25
  • Journal article (peer-reviewed)abstract
    • Phylogenetic relationships among major groups of passeriform birds were studied by analyses of nucleotide sequence data from two nuclear genes, c-myc and RAG-1. The results corroborated both the monophyly of the order Passeriformes, and the major dichotomy into oscine and suboscine passerines previously suggested based on syringeal morphology and DNA-DNA hybridizations. The representatives of the Old World suboscines (families Eurylaimidae, Philepittidae and Pittidae) formed a monophyletic clade. The New World suboscines clustered into two clades. The first contained Conopophaga (Conopophagidae), Furnarius (Furnariidae), Lepidocolaptes (Dendrocolaptidae), Thamnophilus (Formicariidae), and Rhinocrypta (Rhinocryptidae). Previously, the monophyly of this group has been inferred from their possession of a unique, "tracheophone" syrinx, and from DNA-DNA hybridisation data. The second clade of New World suboscines includes Gubernetes and Muscivora (Tyrannidae), Phytotoma (Phytotomidae), Tityra (Cotingidae) and Pipra (Pipridae). This group of families have been considered monophyletic based on morphology (although ambiguously) and DNA-DNA hybridisation. The sister group relationship of Tityra and Phytotoma supports the previously supposed cotingid affinity of Phytotoma. Nuclear DNA data also unambiguously group the lyrebirds Menura with the oscines. The presented results from the analysis of nuclear DNA agree well with morphology and DNA-DNA hybridisation data. The precise age of the divergences studied herein are unknown but based on interpretations of the fossil record of passerine birds many of them might date back to the early Tertiary. The agreement between data from the nuclear DNA and other sources, along with the fact that neither of the studied genes showed sign of saturation, indicate the great potential of these two nuclear genes to resolve very old divergences in birds.
  •  
Skapa referenser, mejla, bekava och länka
  • Result 1-10 of 19

Kungliga biblioteket hanterar dina personuppgifter i enlighet med EU:s dataskyddsförordning (2018), GDPR. Läs mer om hur det funkar här.
Så här hanterar KB dina uppgifter vid användning av denna tjänst.

 
pil uppåt Close

Copy and save the link in order to return to this view