scholarly journals Deep time diversity and the early radiations of birds

2021 ◽  
Vol 118 (10) ◽  
pp. e2019865118
Author(s):  
Yilun Yu ◽  
Chi Zhang ◽  
Xing Xu
Keyword(s):  
Evolutionary History ◽  
Large Scale ◽  
Evolutionary Rate ◽  
Rapid Evolution ◽  
Morphological Data ◽  
Deep Time ◽  
The Third ◽  
Time Diversity ◽  
History Of

Reconstructing the history of biodiversity has been hindered by often-separate analyses of stem and crown groups of the clades in question that are not easily understood within the same unified evolutionary framework. Here, we investigate the evolutionary history of birds by analyzing three supertrees that combine published phylogenies of both stem and crown birds. Our analyses reveal three distinct large-scale increases in the diversification rate across bird evolutionary history. The first increase, which began between 160 and 170 Ma and reached its peak between 130 and 135 Ma, corresponds to an accelerated morphological evolutionary rate associated with the locomotory systems among early stem birds. This radiation resulted in morphospace occupation that is larger and different from their close dinosaurian relatives, demonstrating the occurrence of a radiation among early stem birds. The second increase, which started ∼90 Ma and reached its peak between 65 and 55 Ma, is associated with rapid evolution of the cranial skeleton among early crown birds, driven differently from the first radiation. The third increase, which occurred after ∼40 to 45 Ma, has yet to be supported by quantitative morphological data but gains some support from the fossil record. Our analyses indicate that the bird biodiversity evolution was influenced mainly by long-term climatic changes and also by major paleobiological events such as the Cretaceous–Paleogene (K–Pg) extinction.

scholarly journals Out of the Qinghai-Tibetan Plateau (QTP) and rapid radiation across Eurasia for Allium section Daghestanica (Amaryllidaceae)

AoB Plants ◽  
2021 ◽  
Author(s):  
Min-Jie Li ◽  
Huan-Xi Yu ◽  
Xian-Lin Guo ◽  
Xing-Jin He
Keyword(s):  
Evolutionary History ◽  
Divergence Time ◽  
Time Estimation ◽  
Adjacent Region ◽  
Rapid Radiation ◽  
Divergence Time Estimation ◽  
Species Diversification ◽  
The Third ◽  
Evolutionary Line ◽  
History Of

Abstract The disjunctive distribution (Europe-Caucasus-Asia) and species diversification across Eurasia for the genus Allium sect. Daghestanica has fascinating attractions for researchers aiming to understanding the development and history of the modern Eurasia flora. However, no any studies have been carried out to address the evolutionary history of this section. Based on the nrITS and cpDNA fragments (trnL-trnF and rpl32-trnL), the evolutionary history of the third evolutionary line (EL3) of the genus Allium was reconstructed and we further elucidate the evolutionary line of sect. Daghestanica under this background. Our molecular phylogeny recovered two highly supported clades in sect. Daghestanica: the Clade I includes Caucasian-European species and Asian A. maowenense, A. xinlongense and A. carolinianum collected in Qinghai; the Clade II comprises Asian yellowish tepal species, A. chrysanthum, A. chrysocephalum, A. herderianum, A. rude and A. xichuanense. The divergence time estimation and biogeography inference indicated that Asian ancestor located in the QTP and the adjacent region could have migrated to Caucasus and Europe distributions around the Late Miocene and resulted in further divergence and speciation; Asian ancestor underwent the rapid radiation in the QTP and the adjacent region most likely due to the heterogeneous ecology of the QTP resulted from the orogeneses around 4–3 Mya. Our study provides a picture to understand the origin and species diversification across Eurasia for sect. Daghestanica.

scholarly journals Evolutionary history of zoogeographical regions surrounding the Tibetan Plateau

2020 ◽  
Vol 3 (1) ◽  
Author(s):  
Jiekun He ◽  
Siliang Lin ◽  
Jiatang Li ◽  
Jiehua Yu ◽  
Haisheng Jiang
Keyword(s):  
Tibetan Plateau ◽  
Evolutionary History ◽  
The Tibetan Plateau ◽  
Change Over Time ◽  
Deep Time ◽  
Terrestrial Vertebrates ◽  
History Of ◽  
Striking Change ◽  
Time Periods ◽  
Over Time

AbstractThe Tibetan Plateau (TP) and surrounding regions have one of the most complex biotas on Earth. However, the evolutionary history of these regions in deep time is poorly understood. Here, we quantify the temporal changes in beta dissimilarities among zoogeographical regions during the Cenozoic using 4,966 extant terrestrial vertebrates and 1,278 extinct mammal genera. We identify ten present-day zoogeographical regions and find that they underwent a striking change over time. Specifically, the fauna on the TP was close to the Oriental realm in deep time but became more similar to the Palearctic realms more recently. The present-day zoogeographical regions generally emerged during the Miocene/Pliocene boundary (ca. 5 Ma). These results indicate that geological events such as the Indo-Asian Collision, the TP uplift, and the aridification of the Asian interior underpinned the evolutionary history of the zoogeographical regions surrounding the TP over different time periods.

scholarly journals The evolutionary history of holometabolous insects inferred from transcriptome-based phylogeny and comprehensive morphological data

2014 ◽  
Vol 14 (1) ◽  
pp. 52 ◽  
Author(s):  
Ralph S Peters ◽  
Karen Meusemann ◽  
Malte Petersen ◽  
Christoph Mayer ◽  
Jeanne Wilbrandt ◽  
...  
Keyword(s):  
Evolutionary History ◽  
Morphological Data ◽  
History Of

scholarly journals Three new Cenomanian conifers from El Chango (Chiapas, Mexico) offer a snapshot of the geographic mosaic of the Mesozoic conifer decline

2021 ◽  
Author(s):  
Ixchel Gonzalez-Ramirez ◽  
Sergio RS Cevallos-Ferriz ◽  
Carl Rothfels
Keyword(s):  
Evolutionary History ◽  
Mixed Forest ◽  
Freshwater Ecosystems ◽  
Total Evidence ◽  
Morphological Data ◽  
Phylogenetic Position ◽  
Dominant Group ◽  
Geographic Mosaic ◽  
History Of ◽  
Rare Opportunity

Premise of study: El Chango is a recently discovered quarry that contains extremely well preserved fossils. The Cenomanian age of the locality corresponds to a time when the global flora was transitioning from gymnosperm- to angiosperm-dominated, yet conifers predominate in this locality. These fossils thus provide a rare opportunity to understand the replacement of conifers by angiosperms as the dominant group of plants. Methods: We collected material from El Chango in annual expeditions (2010 to 2014). We selected the three most abundant and best preserved conifer morphotypes and conducted a total-evidence (i.e., including molecular and morphological data) phylogenetic analysis of a sample of 72 extant conifer species plus the three fossils. We use these results to inform our taxonomic decisions. Results: We obtained four equally most-parsimonious trees (consistency index = 44.1%, retention index = 78.8%). Despite ambiguous relationships among some extant taxa, the three fossil conifers had the same phylogenetic position in all four most parsimonious trees; we describe these species as new: Sequoiadendron helicalancifolium sp. nov. (Cupressaceae), and Microcachrys rhomboidea sp. nov. and Dacrydium bifoliosus sp. nov (Podocarpaceae). The ecosystem is interpreted as a coastal humid mixed forest. Conclusions: Our findings contribute to the understanding of Cenomanian equatorialregions, and support the hypothesis of a geographically and ecologically structured rise of angiosperms, with conifers remaining dominant in brackish-water and angiosperms becoming dominant in freshwater-ecosystems. These fossils fill in gaps in the evolutionary history of lineages like Microcachrys, which we demonstrate occurred in the Northern hemisphere before becoming restricted to its current range (Tasmania).

scholarly journals I višap armeni. Appunti per una storia della ricezione

2020 ◽  
Author(s):  
Alessandra Gilibert
Keyword(s):  
Middle Ages ◽  
Large Scale ◽  
South Caucasus ◽  
Political Messages ◽  
Complex Sequence ◽  
The Third ◽  
Third Millennium ◽  
Third Millennium Bce ◽  
History Of ◽  
Unknown Point

Vishaps are large-scale prehistoric stelae decorated with animal reliefs, erected at secluded mountain locations of the South Caucasus. This paper focuses on the vishaps of modern Armenia and traces their history of re-use and manipulations, from the end of the third millennium BCE to the Middle Ages. Since their creation at an unknown point in time before 2100 BCE, vishaps functioned as symbolic anchors for the creation and transmission of religious and political messages: they were torn down, buried, re-worked, re-erected, transformed and used as a surface for graffiti. This complex sequence of re-contextualisations underscores the primacy of mountains as political arenas for the negotiation of religious and ritual meaning.

Host defense mechanisms induce genome instability leading to rapid evolution in an opportunistic fungal pathogen

2021 ◽  
Author(s):  
Amanda Smith ◽  
Levi Morran ◽  
Meleah A. Hickman
Keyword(s):  
Fungal Pathogen ◽  
Defense Mechanisms ◽  
Large Scale ◽  
Genome Instability ◽  
Rapid Evolution ◽  
Genomic Changes ◽  
Opportunistic Fungal Pathogen ◽  
Immunocompromised Hosts ◽  
Stressful Environments

The ability to generate genetic variation facilitates rapid adaptation in stressful environments. The opportunistic fungal pathogen Candida albicans frequently undergoes large-scale genomic changes, including aneuploidy and loss-of heterozygosity (LOH), following exposure to host environments. However, the specific host factors inducing C. albicans genome instability remain largely unknown. Here, we leveraged the genetic tractability of nematode hosts to investigate whether innate immune components, including antimicrobial peptides (AMPs) and reactive oxygen species (ROS), induced host-associated C. albicans genome instability. C. albicans associated with immunocompetent hosts carried multiple large-scale genomic changes including LOH, whole chromosome, and segmental aneuploidies. In contrast, C. albicans associated with immunocompromised hosts deficient in AMPs or ROS production had reduced LOH frequencies and fewer, if any, additional genomic changes. To evaluate if extensive host-induced genomic changes had long-term consequences for C. albicans adaptation, we experimentally evolved C. albicans in either immunocompetent or immunocompromised hosts and selected for increased virulence. C. albicans evolved in immunocompetent hosts rapidly increased virulence, but not in immunocompromised hosts. Taken together, this work suggests that host-produced ROS and AMPs induces genotypic plasticity in C. albicans which facilitates rapid evolution.

The Exponential Nature of Technology

2017 ◽  
Author(s):  
Arlindo Oliveira
Keyword(s):  
Industrial Revolution ◽  
Technological Development ◽  
Exponential Functions ◽  
The Third ◽  
Agricultural Revolution ◽  
Nature Of Technology ◽  
History Of ◽  
Third Industrial Revolution ◽  
Industrial Revolutions

This chapter provides a brief review of the history of technology, covering pre-historical technologies, the agricultural revolution, the first two industrial revolutions, and the third industrial revolution, based on information technology. Evidence is provided that technological development tends to follow an exponential curve, leading to technologies that typically were unpredictable just a few years before. An analysis of a number of exponential trends and behaviors is provided, in order to acquaint the reader with the sometimes surprising properties of exponential growth. In general, exponential functions tend to grow slower than expected in the short term, and faster than expected in the long term. It is this property that make technology evolution very hard to predict.

ARENA

2021 ◽  
pp. 126-165
Author(s):  
James Loxton
Keyword(s):  
Large Scale ◽  
Right Wing ◽  
Left Wing ◽  
Military Rule ◽  
Death Squad ◽  
Powerful Source ◽  
Fourth Section ◽  
The Third ◽  
History Of ◽  
High Level

This chapter examines ARENA in El Salvador and argues that, like the UDI in Chile, its success was the product of authoritarian inheritance and counterrevolutionary struggle. The first section discusses El Salvador’s long history of right-wing military rule. The second section examines the October 1979 coup and the resulting establishment of a left-wing Revolutionary Governing Junta. The third section discusses the intense counterrevolutionary response that the junta triggered. This included large-scale death squad violence, with future ARENA founder Roberto D’Aubuisson playing a key role. The fourth section examines the formation of ARENA in response to an impending transition to competitive elections. The fifth section shows how D’Aubuisson’s role as a high-level official in the pre-1979 military regime endowed ARENA with several valuable resources. The final section discusses how ARENA’s origins in counterrevolutionary struggle served as a powerful source of cohesion.

The Holocaust

2018 ◽  
Author(s):  
George R. Mastroianni
Keyword(s):  
Large Scale ◽  
Social Psychological ◽  
The Holocaust ◽  
Cultural Processes ◽  
History Of ◽  
Situational Pressures

Chapter 2 traces the history of psychological thinking about Hitler, the Nazi accession to power, and, eventually, the Holocaust. Explanations of these phenomena took several forms. Some focused on putative psychopathology, either of Nazi leaders or Germans as a whole; some focused on particular German cultural and social adaptations that were thought to produce particularly obedient and authoritarian individuals; still others emphasized the interaction of some or all of these factors with long-term, large-scale historical and cultural processes. Gordon Allport saw prejudice and racism as central to understanding the Holocaust. After Stanley Milgram’s studies appeared in the early 1960s, genocidal behavior was largely seen by psychologists as an obedient response to situational pressures. Recent decades have brought greater diversity in social psychological explanations of perpetrator behavior in the Holocaust and in genocide more generally.

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