Diversity in obscurity: fossil flowers and the early history of angiosperms

In the second half of the nineteenth century, pioneering discoveries of rich assemblages of fossil plants from the Cretaceous resulted in considerable interest in the first appearance of angiosperms in the geological record. Darwin's famous comment, which labelled the ‘rapid development’ of angiosperms an ‘abominable mystery’, dates from this time. Darwin and his contemporaries were puzzled by the relatively late, seemingly sudden and geographically widespread appearance of modern-looking angiosperms in Late Cretaceous floras. Today, the early diversification of angiosperms seems much less ‘rapid’. Angiosperms were clearly present in the Early Cretaceous, 20–30 Myr before they attained the level of ecological dominance reflected in some mid-Cretaceous floras, and angiosperm leaves and pollen show a distinct pattern of steadily increasing diversity and complexity through this interval. Early angiosperm fossil flowers show a similar orderly diversification and also provide detailed insights into the changing reproductive biology and phylogenetic diversity of angiosperms from the Early Cretaceous. In addition, newly discovered fossil flowers indicate considerable, previously unrecognized, cryptic diversity among the earliest angiosperms known from the fossil record. Lineages that today have an herbaceous or shrubby habit were well represented. Monocotyledons, which have previously been difficult to recognize among assemblages of early fossil angiosperms, were also diverse and prominent in many Early Cretaceous ecosystems.

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A Middle Jurassic abelisaurid from Patagonia and the early diversification of theropod dinosaurs

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2012.0660 ◽

2012 ◽

Vol 279 (1741) ◽

pp. 3170-3175 ◽

Cited By ~ 71

Author(s):

Diego Pol ◽

Oliver W. M. Rauhut

Keyword(s):

South America ◽

Northern Hemisphere ◽

Early Cretaceous ◽

Middle Jurassic ◽

Evolutionary History ◽

Regional Geography ◽

Distinctive Features ◽

Theropod Dinosaurs ◽

Early Diversification ◽

History Of

Abelisaurids are a clade of large, bizarre predatory dinosaurs, most notable for their high, short skulls and extremely reduced forelimbs. They were common in Gondwana during the Cretaceous, but exceedingly rare in the Northern Hemisphere. The oldest definitive abelisaurids so far come from the late Early Cretaceous of South America and Africa, and the early evolutionary history of the clade is still poorly known. Here, we report a new abelisaurid from the Middle Jurassic of Patagonia, Eoabelisaurus mefi gen. et sp. nov., which predates the so far oldest known secure member of this lineage by more than 40 Myr. The almost complete skeleton reveals the earliest evolutionary stages of the distinctive features of abelisaurids, such as the modification of the forelimb, which started with a reduction of the distal elements. The find underlines the explosive radiation of theropod dinosaurs in the Middle Jurassic and indicates an unexpected diversity of ceratosaurs at that time. The apparent endemism of abelisauroids to southern Gondwana during Pangean times might be due to the presence of a large, central Gondwanan desert. This indicates that, apart from continent-scale geography, aspects such as regional geography and climate are important to reconstruct the biogeographical history of Mesozoic vertebrates.

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The Tempo and mode(S) of Prebiotic Evolution

International Astronomical Union Colloquium ◽

10.1017/s0252921100014937 ◽

1997 ◽

Vol 161 ◽

pp. 419-429 ◽

Cited By ~ 1

Author(s):

Antonio Lazcano

Keyword(s):

Origin Of Life ◽

Organic Compounds ◽

Biological Evolution ◽

Current Evidence ◽

Early Diversification ◽

Time Period ◽

The Galaxy ◽

History Of ◽

Widespread Phenomenon ◽

The Origin Of Life

AbstractDifferent current ideas on the origin of life are critically examined. Comparison of the now fashionable FeS/H2S pyrite-based autotrophic theory of the origin of life with the heterotrophic viewpoint suggest that the later is still the most fertile explanation for the emergence of life. However, the theory of chemical evolution and heterotrophic origins of life requires major updating, which should include the abandonment of the idea that the appearance of life was a slow process involving billions of years. Stability of organic compounds and the genetics of bacteria suggest that the origin and early diversification of life took place in a time period of the order of 10 million years. Current evidence suggest that the abiotic synthesis of organic compounds may be a widespread phenomenon in the Galaxy and may have a deterministic nature. However, the history of the biosphere does not exhibits any obvious trend towards greater complexity or «higher» forms of life. Therefore, the role of contingency in biological evolution should not be understimated in the discussions of the possibilities of life in the Universe.

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History—an overview

10.1093/oso/9780198797319.003.0001 ◽

2018 ◽

Author(s):

Oriol Bohigas ◽

Hans A. Weidenmüller

Keyword(s):

Random Matrix Theory ◽

Random Matrix ◽

Matrix Theory ◽

Rapid Development ◽

The Past ◽

History Of ◽

And Mathematics

An overview of the history of random matrix theory (RMT) is provided in this chapter. Starting from its inception, the authors sketch the history of RMT until about 1990, focusing their attention on the first four decades of RMT. Later developments are partially covered. In the past 20 years RMT has experienced rapid development and has expanded into a number of areas of physics and mathematics.

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Amazonia as the Origin and Diversification Area of Didelphidae (Mammalia: Metatheria), and a Review of the Fossil Record of the Clade

Journal of Mammalian Evolution ◽

10.1007/s10914-021-09548-7 ◽

2021 ◽

Author(s):

Mariela C. Castro ◽

Murilo J. Dahur ◽

Gabriel S. Ferreira

Keyword(s):

South America ◽

Amazon Basin ◽

Parametric Models ◽

Isthmus Of Panama ◽

Biogeographic History ◽

Early Diversification ◽

Northern Portion ◽

History Of ◽

Environmental Events ◽

Fossil Records

AbstractDidelphidae is the largest New World radiation of marsupials, and is mostly represented by arboreal, small- to medium-sized taxa that inhabit tropical and/or subtropical forests. The group originated and remained isolated in South America for millions of years, until the formation of the Isthmus of Panama. In this study, we present the first reconstruction of the biogeographic history of Didelphidae including all major clades, based on parametric models and stratified analyses over time. We also compiled all the pre-Quaternary fossil records of the group, and contrasted these data to our biogeographic inferences, as well as to major environmental events that occurred in the South American Cenozoic. Our results indicate the relevance of Amazonia in the early diversification of Didelphidae, including the divergence of the major clades traditionally ranked as subfamilies and tribes. Cladogeneses in other areas started in the late Miocene, an interval of intense shifts, especially in the northern portion of Andes and Amazon Basin. Occupation of other areas continued through the Pliocene, but few were only colonized in Quaternary times. The comparison between the biogeographic inference and the fossil records highlights some further steps towards better understanding the spatiotemporal evolution of the clade. Finally, our results stress that the early history of didelphids is obscured by the lack of Paleogene fossils, which are still to be unearthed from low-latitude deposits of South America.

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Unique lowermost Cambrian small shelly fossils (SSFs) from eastern Yunnan, South China: implications for the early diversification history of animals

Palaeoworld ◽

10.1016/j.palwor.2021.02.001 ◽

2021 ◽

Author(s):

Sena Kono ◽

Yukio Isozaki ◽

Tomohiko Sato ◽

Moriaki Yasuhara ◽

Wei Liu ◽

...

Keyword(s):

South China ◽

Small Shelly Fossils ◽

Early Diversification ◽

History Of

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Implications for the age of South African Devonian rocks in which Tropidoleptus (Brachiopoda) has been found

Geological Magazine ◽

10.1017/s0016756800025024 ◽

1983 ◽

Vol 120 (1) ◽

pp. 51-58 ◽

Cited By ~ 22

Author(s):

A. J. Boucot ◽

C. H. C. Brunton ◽

J. N. Theron

Keyword(s):

South Africa ◽

North America ◽

South African ◽

Early Carboniferous ◽

Fossil Plants ◽

Geological Time ◽

Marine Sedimentation ◽

History Of ◽

Near Shore ◽

First Time

SummaryThe Devonian brachiopod Tropidoleptus is recognized for the first time in South Africa. It is present in the lower part of the Witteberg Group at four widely separated localities. Data regarding the stratigraphical range of the genus elsewhere, combined with information on recently described fossil plants and vertebrates from underlying strata of the upper Bokkeveld Group, suggest that a Frasnian or even Givetian age is reasonable for the lower part of the Witteberg Group. The recognition of Tropidoleptus in a shallow water, near-shore, molluscan association, at the top of the South African marine Devonian sequence, is similar to its occurrence in Bolivia, and suggests a common Malvinokaffric Realm history of shallowing, prior to later Devonian or early Carboniferous non-marine sedimentation. It is noteworthy that Tropidoleptus is now known to occur in ecologically suitable environments around the Atlantic, but is absent from these same environments in Asia and Australia. Tropidoleptus is an excellent example of dispersal in geological time — first appearing in northern Europe and Nova Scotia, then elsewhere in eastern North America and North Africa, followed by South America and South Africa, while continuing in North America.

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Fossil evidence for low gas exchange capacities for Early Cretaceous angiosperm leaves

Paleobiology ◽

10.1666/10015.1 ◽

2011 ◽

Vol 37 (2) ◽

pp. 195-213 ◽

Cited By ~ 32

Author(s):

Taylor S. Feild ◽

Garland R. Upchurch ◽

David S. Chatelet ◽

Timothy J. Brodribb ◽

Kunsiri C. Grubbs ◽

...

Keyword(s):

Gas Exchange ◽

Early Cretaceous ◽

Leaf Gas Exchange ◽

Exchange Capacity ◽

Basal Angiosperm ◽

Photosynthetic Gas Exchange ◽

Angiosperm Evolution ◽

Early Angiosperm ◽

Fossil Evidence ◽

Functional Analyses

The photosynthetic gas exchange capacities of early angiosperms remain enigmatic. Nevertheless, many hypotheses about the causes of early angiosperm success and how angiosperms influenced Mesozoic ecosystem function hinge on understanding the maximum capacity for early angiosperm metabolism. We applied structure-functional analyses of leaf veins and stomatal pore geometry to determine the hydraulic and diffusive gas exchange capacities of Early Cretaceous fossil leaves. All of the late Aptian—early Albian angiosperms measured possessed low vein density and low maximal stomatal pore area, indicating low leaf gas exchange capacities in comparison to modern ecologically dominant angiosperms. Gas exchange capacities for Early Cretaceous angiosperms were equivalent or lower than ferns and gymnosperms. Fossil leaf taxa from Aptian to Paleocene sediments previously identified as putative stem-lineages to Austrobaileyales and Chloranthales had the same gas exchange capacities and possibly leaf water relations of their living relatives. Our results provide fossil evidence for the hypothesis that high leaf gas exchange capacity is a derived feature of later angiosperm evolution. In addition, the leaf gas exchange functions of austrobaileyoid and chloranthoid fossils support the hypothesis that comparative research on the biology of living basal angiosperm lineages reveals genuine signals of Early Cretaceous angiosperm ecophysiology.

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Professional Psychology in Portugal

Psychological Reports ◽

10.2466/pr0.1997.81.3f.1211 ◽

1997 ◽

Vol 81 (3_suppl) ◽

pp. 1211-1222 ◽

Cited By ~ 4

Author(s):

Teresa Fagulha ◽

Richard H. Dana

Keyword(s):

Rapid Development ◽

Well Being ◽

Professional Psychology ◽

Current Status ◽

Environmental Concerns ◽

Advanced Degrees ◽

Professional Degree ◽

History Of ◽

Training Research

This paper describes the history and current status of professional psychology in Portugal where a unique perspective combines training, research, and practical contributions from Europe and the Americas with their own history of psychological tradition and expertise. Training in professional psychology includes Social Psychology and Educational and Vocational Guidance specializations in addition to Clinical Psychology and Psychotherapy and Counseling for the professional degree, Licenciatura. Advanced degrees are offered in Environmental Psychology, Career Development, Social Cognition, and other areas, primarily for academic positions. Research in all of these areas is expected to have applied outcomes that contribute to individual well being and an improved quality of life for the entire population. The result has been a rapid development of an indigenous professional psychology to address mental health, social, and environmental concerns that compel psychological attention and resources worldwide as well as those problems of local and national origins.

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A fossil record of land plant origins from charophyte algae

Science ◽

10.1126/science.abj2927 ◽

2021 ◽

Vol 373 (6556) ◽

pp. 792-796 ◽

Cited By ~ 1

Author(s):

Paul K. Strother ◽

Clinton Foster

Keyword(s):

Fossil Record ◽

Evolutionary History ◽

Phylogenetic Signal ◽

Land Plant ◽

Fossil Plants ◽

Fossil Plant ◽

Molecular Phylogenetic ◽

History Of ◽

Time Gap ◽

Evolutionary Continuity

Molecular time trees indicating that embryophytes originated around 500 million years ago (Ma) during the Cambrian are at odds with the record of fossil plants, which first appear in the mid-Silurian almost 80 million years later. This time gap has been attributed to a missing fossil plant record, but that attribution belies the case for fossil spores. Here, we describe a Tremadocian (Early Ordovician, about 480 Ma) assemblage with elements of both Cambrian and younger embryophyte spores that provides a new level of evolutionary continuity between embryophytes and their algal ancestors. This finding suggests that the molecular phylogenetic signal retains a latent evolutionary history of the acquisition of the embryophytic developmental genome, a history that perhaps began during Ediacaran-Cambrian time but was not completed until the mid-Silurian (about 430 Ma).

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