Evolutionary Patterns in the History of Permo-Triassic and Cenozoic Synapsid Predators

2002 ◽  
Vol 8 ◽  
pp. 267-288 ◽  
Author(s):  
Blaire Van Valkenburgh ◽  
Ian Jenkins
Keyword(s):  
Fossil Record ◽  
Late Carboniferous ◽  
Second Phase ◽  
Evolutionary Patterns ◽  
Large Size ◽  
Jaw Mechanics ◽  
History Of ◽  
Trends Over Time ◽  
Energetic Constraints ◽  
Over Time

Synapsids include modern mammals and their fossil ancestors, the non-mammalian synapsids, or ‘mammal-like reptiles' of old classifications. The synapsid fossil record extends from the Late Carboniferous to the present, a span of nearly 300 million years. However, it can be broken into two distinct phases of diversification, separated by about 150 million years. The first phase extends from the Late Carboniferous to the mid-Triassic, includes the first large land predators on Earth, and is almost entirely non-mammalian. The second phase begins about 65 million years ago after the demise of the dinosaurs, includes only mammals, and extends to the present. In this overview of synapsid predators, we emphasize terrestrial species of large size, and their adaptations for killing and feeding, rather than locomotion. Despite fundamental differences in jaw mechanics and tooth morphology, there are significant parallels in the non-mammalian and mammalian radiations of synapsid predators. Both groups evolve sabertooth forms more than once, and both evolve short-snouted, powerful biting forms. In addition, both the Late Carboniferous—Triassic and Cenozoic phases are characterized by repeated patterns of clade replacement, in which one or a few clades evolve large size and seem to dominate the carnivore guild for several million years, but then decline and are replaced by new taxa. Moreover, within both ancient and Cenozoic predator clades, there are parallel trends over time toward increased body size and hypercarnivory that likely result from a combination of interspecific competition and energetic constraints.

Long/Short Term Influences on Change

1999 ◽  
Vol 9 ◽  
pp. 309-318
Author(s):  
Kaustuv Roy
Keyword(s):  
Fossil Record ◽  
The Other ◽  
Short Term ◽  
Geologic Time ◽  
Number Of Species ◽  
Higher Taxa ◽  
Terrestrial Habitats ◽  
History Of ◽  
Using Data ◽  
Over Time

Change has been the rule in the history of life. Mammals today dominate the terrestrial habitats where dinosaurs once held sway. In modern oceans, ecologists can study many species of arthropods, but trilobites are long gone. Using data from the fossil record, David Raup estimated that only about one in a thousand species that ever lived on this planet is still alive today (Raup, 1991). On the other hand, the number of species and higher taxa has increased steadily over geologic time. Thus the history of life is essentially a history of turnover of species, lineages and higher taxa over time.

Long / Short Term Influences on Change

2002 ◽  
Vol 11 ◽  
pp. 249-256
Author(s):  
Kaustuv Roy
Keyword(s):  
Fossil Record ◽  
The Other ◽  
Short Term ◽  
Geologic Time ◽  
Number Of Species ◽  
Higher Taxa ◽  
Terrestrial Habitats ◽  
History Of ◽  
Using Data ◽  
Over Time

Change has been the rule in the history of life. Mammals today dominate the terrestrial habitats where dinosaurs once held sway. In modern oceans, ecologists can study many species of arthropods, but trilobites are long gone. Using data from the fossil record, David Raup estimated that only about one in a thousand species that ever lived on this planet is still alive today (Raup, 1991). On the other hand, the number of species and higher taxa has increased steadily over geologic time. Thus the history of life is essentially a history of turnover of species, lineages, and higher taxa over time.

scholarly journals Evolvability and the Fossil Record

2021 ◽  
Author(s):  
Alan C Love ◽  
Mark Grabowski ◽  
David Houle ◽  
Lee Hsiang Liow ◽  
Arthur Porto ◽  
...  
Keyword(s):  
Fossil Record ◽  
Evolutionary Biology ◽  
Evolutionary Developmental Biology ◽  
Theoretical Studies ◽  
Evolutionary Patterns ◽  
History Of ◽  
Measurement And Testing ◽  
Ecological Success ◽  
Relevant Variation ◽  
Phylogenetic Models

The concept of evolvability—the capacity of a population to produce and maintain evolutionarily relevant variation—has become increasingly prominent in evolutionary biology. Although paleontology has a long history of investigating questions of evolvability, often invoking different but allied terminology, the study of evolvability in the fossil record has seemed intrinsically problematic. How can we surmount difficulties in disentangling whether the causes of evolutionary patterns arise from variational properties of traits or lineages rather than due to selection and ecological success? Despite these challenges, the fossil record is unique in offering growing sources of data that span millions of years and therefore capture evolutionary patterns of sustained duration and significance otherwise inaccessible to evolutionary biologists. Additionally, there are a variety of strategic possibilities for combining prominent neontological approaches to evolvability with those from paleontology. We illustrate three of these possibilities with quantitative genetics, evolutionary developmental biology, and phylogenetic models of macroevolution. In conclusion, we provide a methodological schema that focuses on the conceptualization, measurement, and testing of hypotheses to motivate and provide guidance for future empirical and theoretical studies of evolvability in the fossil record.

A Historical and Bibliometric Analysis of the Development of Agile

2022 ◽  
pp. 107-121
Author(s):  
Cherie C. Trumbach ◽  
Kenneth R. Walsh ◽  
Sathiadev Mahesh
Keyword(s):  
Life Cycle ◽  
Bibliometric Analysis ◽  
Research Trends ◽  
Underlying Structure ◽  
Product Complexity ◽  
History Of ◽  
Trends Over Time ◽  
Traditional Approaches ◽  
Over Time ◽  
The Web

This chapter starts with a brief history of software development from a summary of traditional approaches and presents the conditions that led to agile approaches such as product complexity, shortened life cycle of the market and eventually to the widespread acceptance of Scrum. The authors then compare the narrative to the bibliometric analysis of abstract records that can be found in the Web of Science database. They parse the terms from the abstract records to identify research trends over time and map the underlying structure of agile research. Finally, they consider the future of Agile-Scrum in light of the current pandemic.

A Historical and Bibliometric Analysis of the Development of Agile

2021 ◽  
pp. 1-15
Author(s):  
Cherie C. Trumbach ◽  
Kenneth R. Walsh ◽  
Sathiadev Mahesh
Keyword(s):  
Life Cycle ◽  
Bibliometric Analysis ◽  
Research Trends ◽  
Underlying Structure ◽  
Product Complexity ◽  
History Of ◽  
Trends Over Time ◽  
Traditional Approaches ◽  
Over Time ◽  
The Web

This chapter starts with a brief history of software development from a summary of traditional approaches and presents the conditions that led to agile approaches such as product complexity, shortened life cycle of the market and eventually to the widespread acceptance of Scrum. The authors then compare the narrative to the bibliometric analysis of abstract records that can be found in the Web of Science database. They parse the terms from the abstract records to identify research trends over time and map the underlying structure of agile research. Finally, they consider the future of Agile-Scrum in light of the current pandemic.

A History of Violence

2020 ◽  
Vol 11 (1) ◽  
pp. 36-67
Author(s):  
Cédric Cotter ◽  
Ellen Policinski
Keyword(s):  
International Committee ◽  
Red Cross ◽  
International Humanitarian Law ◽  
Humanitarian Law ◽  
Academic Journal ◽  
Cambridge University ◽  
History Of ◽  
Trends Over Time ◽  
The Law ◽  
Over Time

The International Review of the Red Cross, an academic journal produced by the International Committee of the Red Cross (icrc) and published by Cambridge University Press, traces its origins back more than 150 years. Throughout its existence, the publication has featured international humanitarian law (ihl) prominently. Because of this, it is possible to trace how the icrc was communicating publicly about ihl since 1869, allowing researchers to draw conclusions about how that body of law has evolved. In this article, the authors divide the history of the Review into five time periods, looking at trends over time as ihl was established as a body of law, was expanded to address trends in the ways war was waged, was disseminated and promoted to the international community, and how it is interpreted in light of current conflicts. Based on the way the law has been represented in the Review, the authors draw conclusions about the evolution of the law itself over time, and lessons this may provide for those who seek to influence the future development of the law regulating armed conflict.

scholarly journals Evolvability in the fossil record

Paleobiology ◽  
2021 ◽  
pp. 1-24
Author(s):  
Alan C. Love ◽  
Mark Grabowski ◽  
David Houle ◽  
Lee Hsiang Liow ◽  
Arthur Porto ◽  
...  
Keyword(s):  
Fossil Record ◽  
Evolutionary Biology ◽  
Evolutionary Developmental Biology ◽  
Evolutionary Patterns ◽  
Fundamental Difficulty ◽  
History Of ◽  
Measurement And Testing ◽  
Ecological Success ◽  
Relevant Variation ◽  
Phylogenetic Models

Abstract The concept of evolvability—the capacity of a population to produce and maintain evolutionarily relevant variation—has become increasingly prominent in evolutionary biology. Paleontology has a long history of investigating questions of evolvability, but paleontological thinking has tended to neglect recent discussions, because many tools used in the current evolvability literature are challenging to apply to the fossil record. The fundamental difficulty is how to disentangle whether the causes of evolutionary patterns arise from variational properties of traits or lineages rather than being due to selection and ecological success. Despite these obstacles, the fossil record offers unique and growing sources of data that capture evolutionary patterns of sustained duration and significance otherwise inaccessible to evolutionary biologists. Additionally, there exist a variety of strategic possibilities for combining prominent neontological approaches to evolvability with those from paleontology. We illustrate three of these possibilities with quantitative genetics, evolutionary developmental biology, and phylogenetic models of macroevolution. In conclusion, we provide a methodological schema that focuses on the conceptualization, measurement, and testing of hypotheses to motivate and provide guidance for future empirical and theoretical studies of evolvability in the fossil record.

The Path of Standard Albanian Language Formation

2018 ◽  
Vol 5 (2) ◽  
pp. 106-115
Author(s):  
Sindorela Doli Kryeziu
Keyword(s):  
Single Unit ◽  
Cultural Factors ◽  
Language History ◽  
Whole Process ◽  
History Of ◽  
Social And Cultural Factors ◽  
Cultural Body ◽  
Over Time ◽  
Language Literature

Abstract In our paper we will talk about the whole process of standardization of the Albanian language, where it has gone through a long historical route, for almost a century.When talking about standard Albanian language history and according to Albanian language literature, it is often thought that the Albanian language was standardized in the Albanian Language Orthography Congress, held in Tirana in 1972, or after the publication of the Orthographic Rules (which was a project at that time) of 1967 and the decisions of the Linguistic Conference, a conference of great importance that took place in Pristina, in 1968. All of these have influenced chronologically during a very difficult historical journey, until the standardization of the Albanian language.Considering a slightly wider and more complex view than what is often presented in Albanian language literature, we will try to describe the path (history) of the standard Albanian formation under the influence of many historical, political, social and cultural factors that are known in the history of the Albanian people. These factors have contributed to the formation of a common state, which would have, over time, a common standard language.It is fair to think that "all activity in the development of writing and the Albanian language, in the field of standardization and linguistic planning, should be seen as a single unit of Albanian culture, of course with frequent manifestations of specific polycentric organization, either because of divisions within the cultural body itself, or because of the external imposition"(Rexhep Ismajli," In Language and for Language ", Dukagjini, Peja, 1998, pp. 15-18.)

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