Progress and future directions in archosaur phylogenetics

2001 ◽  
Vol 75 (6) ◽  
pp. 1185-1201 ◽  
Author(s):  
Christopher A. Brochu
Keyword(s):  
Phylogenetic Relationships ◽  
Fossil Record ◽  
Middle Triassic ◽  
Basic Structure ◽  
Sources Of Information ◽  
Crown Group ◽  
Future Directions ◽  
Close Relationship ◽  
Divergence Timing

The basic structure of archosaurian phylogeny is understood to include two primary crown-group lineages—one leading to living crocodiles and including a broad diversity of Triassic animals (e.g., phytosaurs, rauisuchians, aetosaurs), and another leading to dinosaurs (living and extinct). These lineages were established by the middle Triassic. A few extinct groups remain controversial, such as the pterosaurs, and debate persists over the phylogenetic relationships among extant bird lineages, which have proved difficult to resolve, and divergence timing estimates within Aves and Crocodylia remain the source of contention. A few analyses support a close relationship between archosaurs and turtles, or even a nesting of turtles within Archosauria. All sources of information used to resolve these issues have weaknesses, and these problems all involve highly derived lineages when they first appear in the fossil record.

scholarly journals Neopterygian phylogeny: the merger assay

2018 ◽  
Vol 5 (3) ◽  
pp. 172337 ◽  
Author(s):  
Adriana López-Arbarello ◽  
Emilia Sferco
Keyword(s):  
Phylogenetic Relationships ◽  
Late Jurassic ◽  
Middle Triassic ◽  
Late Triassic ◽  
Future Research ◽  
Phylogenetic Hypothesis ◽  
Monophyletic Clade ◽  
Crown Group ◽  
Rapid Radiation ◽  
Cladistic Analyses

The phylogenetic relationships of the recently described genus † Ticinolepis from the Middle Triassic of the Monte San Giorgio are explored through cladistic analyses of the so far largest morphological dataset for fossil actinopterygians, including representatives of the crown-neopterygian clades Halecomorphi, Ginglymodi and Teleostei, and merging the characters from previously published systematic studies together with newly proposed characters. † Ticinolepis is retrieved as the most basal Ginglymodi and our results support the monophyly of Teleostei and Holostei, as well as Halecomorphi and Ginglymodi within the latter clade. The patterns of relationships within these clades mostly agree with those of previous studies, although a few important differences require future research. According to our results, ionoscopiforms are not monophyletic, caturids are not amiiforms and leptolepids and luisiellids form a monophyletic clade. Our phylogenetic hypothesis confirms the rapid radiation of the holostean clades Halecomorphi and Ginglymodi during the Early and Middle Triassic and the radiation of pholidophoriform teleosts during the Late Triassic. Crown-group Halecomorphi have an enormous ghost lineage throughout half of the Mesozoic, but ginglymodians and teleosts show a second radiation during the Early Jurassic. The crown-groups of Halecomorphi, Ginglymodi and Teleostei originated within parallel events of radiation during the Late Jurassic.

Future direction of suicidal risk assessment

2016 ◽  
Vol 33 (S1) ◽  
pp. S68-S68
Author(s):  
H. Blasco-Fontecilla
Keyword(s):  
At Risk ◽  
Suicidal Behavior ◽  
Suicidal Risk ◽  
Sources Of Information ◽  
Future Directions ◽  
Suicide Prediction ◽  
Competing Interest ◽  
Future Direction ◽  
Near Future ◽  
Subjective Reports

Objectiveto explore future directions on the assessment of the risk of suicidal behavior (SB).Methodsnarrative review of current and future methods to improving the assessment of the risk of suicidal behavior (SB).ResultsPredicting future SB is a long-standing goal. Currently, the identification of individuals at risk of SB is based on clinician's subjective reports. Unfortunately, most individuals at risk of SB often do not disclose their suicidal thoughts. In the near future, predicting the risk of SB will be enhanced by: (1) introducing objective, reliable measures – i.e. biomarkers – of suicide risk; (2) selecting the most discriminant variables, and developing more accurate measures – i.e. questionnaires – and models for suicide prediction; (3) incorporating new sources of information – i.e. facebook, online monitoring; (4) applying novel methodological instruments such as data mining, or computer adaptive testing; and, (5) most importantly, combining predictors from different domains (clinical, neurobiological and cognitive).ConclusionsGiven the multi-determined nature of SB, a combination of clinical, neuropsychological, biological, and neuroimaging factors, among other might help overcome current limitations in the prediction of SB. Furthermore, given the complexity of prediction of future SB, currently our efforts should be focused on the prevention of SB.Disclosure of interestThe author has not supplied his declaration of competing interest.

scholarly journals A review of the systematic biology of fossil and living bony-tongue fishes, Osteoglossomorpha (Actinopterygii: Teleostei)

2018 ◽  
Vol 16 (3) ◽  
Author(s):  
Eric J. Hilton ◽  
Sébastien Lavoué
Keyword(s):  
Phylogenetic Relationships ◽  
Fossil Record ◽  
The State ◽  
Heterogeneous Group ◽  
Marine Deposits ◽  
Evolutionary Study ◽  
Future Needs ◽  
Phylogenetic Affinities ◽  
Basal Position ◽  
Systematic Biology

ABSTRACT The bony-tongue fishes, Osteoglossomorpha, have been the focus of a great deal of morphological, systematic, and evolutionary study, due in part to their basal position among extant teleostean fishes. This group includes the mooneyes (Hiodontidae), knifefishes (Notopteridae), the abu (Gymnarchidae), elephantfishes (Mormyridae), arawanas and pirarucu (Osteoglossidae), and the African butterfly fish (Pantodontidae). This morphologically heterogeneous group also has a long and diverse fossil record, including taxa from all continents and both freshwater and marine deposits. The phylogenetic relationships among most extant osteoglossomorph families are widely agreed upon. However, there is still much to discover about the systematic biology of these fishes, particularly with regard to the phylogenetic affinities of several fossil taxa, within Mormyridae, and the position of Pantodon. In this paper we review the state of knowledge for osteoglossomorph fishes. We first provide an overview of the diversity of Osteoglossomorpha, and then discuss studies of the phylogeny of Osteoglossomorpha from both morphological and molecular perspectives, as well as biogeographic analyses of the group. Finally, we offer our perspectives on future needs for research on the systematic biology of Osteoglossomorpha.

scholarly journals USTAZ ABU BAKAR AL-BAQIR: ULAMA DAN PEJUANG KEMERDEKAAN TANAH MELAYU

2018 ◽  
Author(s):  
KAMARUL AFENDEY BIN HAMIMI ◽  
AHMAD ZULLAILI BIN ZAMRI
Keyword(s):  
Religious Education ◽  
Qualitative Methodology ◽  
Primary Sources ◽  
Religious Leader ◽  
Sources Of Information ◽  
Secondary Sources ◽  
British Rule ◽  
National Archives ◽  
Close Relationship ◽  
Relationship Of

Kertas kerja ini menganalisis peranan Ustaz Abu Bakar al-Baqir iaitu lama reformis tempatan yang konsisten menentang British sehingga terpenjara pada 1948. Beliau turut menubuhkan Maahad al-Ehya Assyariff untuk memodenkan sistem pendidikan pondok di samping meniupkan semangat kemerdekaan kepada pelajar dan masyarakat di sekelilingnya. Objektif kajian ini adalah untuk mengetengahkan sumbangan Ustaz Abu Bakar al-Baqir sebagai seorang ulama dan pejuang kemerdekaan menentang British sekitar 1934 sehingga 1957 di Perak. Kajian ini berbentuk historiografi yang menggunakan kaedah kualitatif dengan pendekatan analisis kandungan. Dua jenis sumber digunakan dalam kajian ini iaitu sumber primer dan sekunder. Sumber primer adalah seperti mendapatkan dokumen dan fail di Arkib Negara Malaysia, sumber pejabat kolonial British di samping menemu bual ahli keluarga dan murid Ustaz Abu Bakar al-Baqir. Sumber sekunder pula diperoleh melalui buku, surat khabar dan kertas kerja seminar yang berkaitan dengan perjuangan beliau. Hasil kajian mendapati para pelajarnya terdedah dengan semangat kemerdekaan ini ekoran guru-guru reformis dari Indonesia yang terdedah dengan perjuangan menentang Belanda mengajar di Maahad al-Ehya Assyariff. Selain itu, hubungan baik Ustaz Abu Bakar al-Baqir dengan Ibrahim Yaakub selaku penggerak Kesatuan Melayu Muda (KMM) dan Dr. Burhanuddin al-Helmy yang memimpin Parti Kebangsaan Melayu Muda (PKMM) menjadikan Maahad al-Ehya Assyariff sebagai markas politik menentang British sehingga tertubuhnya Parti Hizbul Muslimin di bawah pimpinan Ustaz Abu Bakar al-Baqir. Kata kunci: Maahad al-Ehya Assyariff, Hizbul Muslimin, British, Kaum Muda, Parti Kebangsaan Melayu Malaya (PKMM), Kesatuan Melayu Muda (KMM). This paper attempts to analyze the role played by Ustaz Abu Bakar al-Baqir, a local reformist religious leader who consistently opposed the British until he was imprisoned by them in 1948. He established the Maahad al-Ehya Assyariff with the aim of modernizing the religious education system besides stoking the spirit of freedom among his students and the society around him. The objective of this study is to highlight the contributions of Ustaz Abu Bakar al-Baqir as a religious leader as well as a freedom fighter who opposed British rule in Perak from around 1934 until 1957. This is a historiographical research which uses qualitative methodology with a content analysis approach. Two different sources of information are used for this study namely primary and secondary sources. Primary sources include documents and files from the Malaysian National Archives and official documents from the British Colonial office, besides interviewing family members as well as former students of Ustaz Abu Bakar al-Baqir. On the other hand, secondary sources include books, newspapers and seminar report relating to his struggle. The findings of the study show that his students were exposed to the struggle for Independence through the direct influence of the reformist teachers from Indonesia who were teaching at the Maahad al-Ehya Assyariff. These teachers had already been involved in the fight against the Dutch colonialists in Indonesia. In addition to this, the close relationship of Ustaz Abu Bakar al-Baqir with Ibrahim Yaakub, the primemover of Kesatuan Melayu Muda (KMM) and Dr. Burhanuddin al-Helmy, the leader of Parti Kebangsaan Melayu Muda (PKMM), projected Maahadal-Ehya Assyariff as the political front that opposed British rule until the founding of the Parti Hizbul Muslimin under the leadership of Ustaz Abu Bakar al-Baqir. Keywords: Maahad al-Ehya Assyariff, Hizbul Muslimin, British, Kaum Muda, Malay Nationalist Party (MNP), Young Malays Union.

scholarly journals Early fossil record of Euarthropoda and the Cambrian Explosion

2018 ◽  
Vol 115 (21) ◽  
pp. 5323-5331 ◽  
Author(s):  
Allison C. Daley ◽  
Jonathan B. Antcliffe ◽  
Harriet B. Drage ◽  
Stephen Pates
Keyword(s):  
Fossil Record ◽  
Trace Fossils ◽  
Cambrian Explosion ◽  
Burgess Shale ◽  
Crown Group ◽  
Total Group ◽  
Stem Lineage ◽  
Coherent Picture ◽  
Insight Into ◽  
Phosphate Deposits

Euarthropoda is one of the best-preserved fossil animal groups and has been the most diverse animal phylum for over 500 million years. Fossil Konservat-Lagerstätten, such as Burgess Shale-type deposits (BSTs), show the evolution of the euarthropod stem lineage during the Cambrian from 518 million years ago (Ma). The stem lineage includes nonbiomineralized groups, such as Radiodonta (e.g., Anomalocaris) that provide insight into the step-by-step construction of euarthropod morphology, including the exoskeleton, biramous limbs, segmentation, and cephalic structures. Trilobites are crown group euarthropods that appear in the fossil record at 521 Ma, before the stem lineage fossils, implying a ghost lineage that needs to be constrained. These constraints come from the trace fossil record, which show the first evidence for total group Euarthropoda (e.g., Cruziana, Rusophycus) at around 537 Ma. A deep Precambrian root to the euarthropod evolutionary lineage is disproven by a comparison of Ediacaran and Cambrian lagerstätten. BSTs from the latest Ediacaran Period (e.g., Miaohe biota, 550 Ma) are abundantly fossiliferous with algae but completely lack animals, which are also missing from other Ediacaran windows, such as phosphate deposits (e.g., Doushantuo, 560 Ma). This constrains the appearance of the euarthropod stem lineage to no older than 550 Ma. While each of the major types of fossil evidence (BSTs, trace fossils, and biomineralized preservation) have their limitations and are incomplete in different ways, when taken together they allow a coherent picture to emerge of the origin and subsequent radiation of total group Euarthropoda during the Cambrian.

The oldest Diptera (Insecta) from the Upper Buntsandstein (early Middle Triassic) of Europe

Zootaxa ◽  
2021 ◽  
Vol 5067 (1) ◽  
pp. 135-143
Author(s):  
ELENA D. LUKASHEVICH
Keyword(s):  
Fossil Record ◽  
New Genus ◽  
Middle Triassic ◽  
Insect Fauna ◽  
The Family ◽  
Lower Franconia ◽  
Grès À Voltzia ◽  
Early Middle Triassic

The fossil record of Triassic Diptera is still poor, with the oldest dipteran assemblage described from the Upper Buntsandstein of the ‘Grès à Voltzia’ Formation (early Anisian, France). From the stratigraphically closest insect fauna of the Röt Formation of Lower Franconia, Germany, the first Diptera, Bashkonia franconica gen. et sp. nov. is described based on an isolated wing. The new genus is assigned to the family Nadipteridae, bridging the gap between two other genera included.  

Sign in / Sign up

Export Citation Format

Share Document