Evolution and extinction can occur rapidly: a modeling approach

Fossil record of Earth describing the last 500 million years is characterized by evolution discontinuity as well as recurring global extinctions of some species and their replacement by new types, the causes of which are still debate. We developed a model of evolutionary self-development of a large ecosystem. This model of biota evolution based on the universal laws of living systems functioning: reproduction, dependence of reproduction efficiency and mortality on biota density, mutational variability in the process of reproduction and selection of the most adapted individuals. We have shown that global extinctions and phases of rapid growth and biodiversity stasis can be a reflection of the emergence of bistability in a self-organizing system, which is the Earth’s biota. Bistability was found to be characteristic only for ecosystems with predominant sexual reproduction. The reason for the transition from one state to another is the selection of the most adapted individuals. That is, we explain the characteristics of the Earth’s fossil record during the last 500 million years by the internal laws of Earth’s ecosystem functioning, which appeared at a certain stage of evolution as a result of the emergence of life forms with an increased adaptive diversification associated with sexual dimorphism.

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A modern scleractinian coral with a two-component calcite–aragonite skeleton

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.2013316117 ◽

2020 ◽

pp. 202013316

Author(s):

Jarosław Stolarski ◽

Ismael Coronado ◽

Jack G. Murphy ◽

Marcelo V. Kitahara ◽

Katarzyna Janiszewska ◽

...

Keyword(s):

Calcium Carbonate ◽

Southern Ocean ◽

Phylogenetic Relationship ◽

Fossil Record ◽

Scleractinian Coral ◽

Scleractinian Corals ◽

Marine Organisms ◽

Close Phylogenetic Relationship ◽

Two Component ◽

Selection Of

One of the most conserved traits in the evolution of biomineralizing organisms is the taxon-specific selection of skeletal minerals. All modern scleractinian corals are thought to produce skeletons exclusively of the calcium-carbonate polymorph aragonite. Despite strong fluctuations in ocean chemistry (notably the Mg/Ca ratio), this feature is believed to be conserved throughout the coral fossil record, spanning more than 240 million years. Only one example, the Cretaceous scleractinian coral Coelosmilia (ca. 70 to 65 Ma), is thought to have produced a calcitic skeleton. Here, we report that the modern asymbiotic scleractinian coral Paraconotrochus antarcticus living in the Southern Ocean forms a two-component carbonate skeleton, with an inner structure made of high-Mg calcite and an outer structure composed of aragonite. P. antarcticus and Cretaceous Coelosmilia skeletons share a unique microstructure indicating a close phylogenetic relationship, consistent with the early divergence of P. antarcticus within the Vacatina (i.e., Robusta) clade, estimated to have occurred in the Mesozoic (ca. 116 Mya). Scleractinian corals thus join the group of marine organisms capable of forming bimineralic structures, which requires a highly controlled biomineralization mechanism; this capability dates back at least 100 My. Due to its relatively prolonged isolation, the Southern Ocean stands out as a repository for extant marine organisms with ancient traits.

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Selection of Winter and Summer Annual Life Forms in Populations of Senecio sylvaticus L.1)1Dedicated to Prof. Dr. H. Meusel, Halle (Saale), on the occasion of his 80th birthday.

Flora ◽

10.1016/s0367-2530(17)30412-7 ◽

1989 ◽

Vol 182 (3-4) ◽

pp. 221-231 ◽

Cited By ~ 7

Author(s):

W.H.O. Ernst

Keyword(s):

Life Forms ◽

80Th Birthday ◽

Senecio Sylvaticus ◽

Selection Of

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Reflection

10.1093/oso/9780190087265.003.0016 ◽

2021 ◽

pp. 317-325

Author(s):

Alison Hanson ◽

Rafael Yuste

Keyword(s):

Nervous System ◽

Neuronal Activity ◽

Default Mode Network ◽

External Environment ◽

Life Forms ◽

Emergent Property ◽

The Self ◽

Living Systems ◽

Spontaneous Neuronal Activity ◽

Prevailing View

A prevailing view considers the self a property of only the most evolutionarily advanced animals. We propose that a “protoself’ is already present in simple life forms and may be an inherent aspect of all living systems. A separation of the “self” from the “outside” world allows organisms to model the external environment and to act on it. The appearance of the nervous system in larger organisms, initially necessary for speed, enabled the generation of more sophisticated models of the environment and the organism that could be harnessed for more accurate predictions of the future. Spontaneous neuronal activity, such as the default mode network which is prevalent in humans, may serve as an integrator of the model, physically implementing the self as an emergent property.

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Predicting evolution in diverse communities

The Evolutionary Biology of Species ◽

10.1093/oso/9780198749745.003.0009 ◽

2019 ◽

pp. 167-188

Author(s):

Timothy G. Barraclough

Keyword(s):

Microbial Community ◽

Ecosystem Functioning ◽

Evolutionary Dynamics ◽

Control Measures ◽

Living Systems ◽

Human Populations ◽

Focal Species ◽

Diverse Communities ◽

Challenges And Opportunities ◽

Disease Agent

Following the outline of basic theory and evidence in chapters 7 and 8, this chapter sets the challenge of attempting to predict evolutionary dynamics in realistically diverse communities. Many challenges and opportunities facing human populations rely on being able to predict living systems. Even when a single focal species such as a pest or disease agent is of particular concern, its dynamics and responses to control measures always depend on interactions with a diverse set of other species. Even when the focus is on whole-ecosystem functioning, that depends on trait responses of constituent species. The chapter outlines several case studies where a multispecies evolutionary approach is required, including managing marine fisheries, controlling crop pests, and managing human microbiomes for improved health. To illustrate possible ways forwards, a model of evolution in a microbial community is presented, and possible methods for tracking evolution in diverse communities are discussed.

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Aggression in female mammals: Is it really rare?

Behavioral and Brain Sciences ◽

10.1017/s0140525x9926181x ◽

1999 ◽

Vol 22 (2) ◽

pp. 218-218 ◽

Cited By ~ 2

Author(s):

Paul F. Brain

Keyword(s):

Sexual Dimorphism ◽

Short Duration ◽

Physical Aggression ◽

Animal Studies ◽

Human Values ◽

Sexual Competition ◽

Laboratory Rodents ◽

Selection Of

The view that female mammals are more docile appears to arise in part from imposing human values on animal studies. Many reports of sexual dimorphism in physical aggression favouring the male in laboratory rodents appear to select circumstances where that expectation is supported. Other situations that favour the expression of conflict in females have been (until recently) relatively little studied. Although female rodents generally do not show the “ritualised” forms of conflict that characterise male sexual competition, they can use notably damaging strategies (especially if they are of short duration). Such considerations might weigh in the selection of strategies by our own species.

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General discussion after session V

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1988.0073 ◽

1988 ◽

Vol 325 (1587) ◽

pp. 611-618 ◽

Cited By ~ 1

Keyword(s):

Origin Of Life ◽

Time Perspective ◽

Applied Mathematics ◽

Building Blocks ◽

Living Systems ◽

Organic Chemical ◽

General Terms ◽

The Earth ◽

The Origin Of Life ◽

Emergence Of Life

N. C. Wickramasinghe ( Department of Applied Mathematics and Astronomy, University College, Cardiff, U. K. ). The question of the origin of life is, of course, one of the most important scientific questions and it is also one of the most difficult. One is inevitably faced here with a situation where there are very few empirical facts of direct relevance and perhaps no facts relating to the actual transition from organic material to material that can even remotely be described as living. The time perspective of events that relate to this problem has already been presented by Dr Chang. Uncertainty still persists as to the actual first moment of the origin or the emergence of life on the Earth. At some time between 3800 and 3300 Ma BP the first microscopic living systems seem to have emerged. There is a definite moment in time corresponding to a sudden appearance of cellular-type living systems. Now, traditionally the evolution of carbonaceous compounds which led to the emergence of life on Earth could be divided into three principal steps and I shall just remind you what those steps are. The first step is the production of chemical building blocks that lead to the origin of the organic molecules necessary as a prerequisite for the evolution of life. Step two can be described in general terms as prebiotic evolution, the arrangement of these chemical units into some kind of sequence of precursor systems that come almost up to life but not quite; and then stage three is the early biological evolution which actually effects the transition from proto-cellular organic-type forms into truly cellular living systems. The transition is from organic chemistry, prebiotic chemistry to biochemistry. Those are the three principal stages that have been defined by traditional workers in the field, the people who, as Dr Chang said, have had the courage to make these queries and attempt to answer them. Ever since the classic experiments where organic materials were synthesized in the laboratory a few decades back, it was thought that the first step, the production of organic chemical units, is important for the origin of life on the Earth, and that this had to take place in some location on the Earth itself.

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Random Models in Paleobiology

Short Courses in Paleontology ◽

10.1017/s2475263000002154 ◽

1991 ◽

Vol 4 ◽

pp. 123-135

Author(s):

Philip W. Signor

Keyword(s):

Everyday Life ◽

Morphological Variation ◽

Fossil Record ◽

Vast Number ◽

Subjective Judgment ◽

Random Models ◽

Selection Of

The fossil record is replete with patterns. Nearly two centuries of intensive paleontological research has produced a vast number of apparent patterns: stratigraphic and temporal distributions of taxa, paleogeographic distributions, paleoecological relationships, patterns of co-occurrence, morphology and morphological variation, and so forth. Many of these patterns reflect the interplay of important intrinsic processes operating within the biosphere and extrinsic influences acting from without. Others, however, follow from the ordinary processes of everyday life and require no special explanation. How, then, are inquiring paleontologists to separate meaningful patterns from the meaningless? For the most part, the selection of patterns appropriate for further study and explication has remained a matter of subjective judgment.

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The Weevil Fauna Preserved in Burmese Amber—Snapshot of a Unique, Extinct Lineage (Coleoptera: Curculionoidea)

Diversity ◽

10.3390/d11010001 ◽

2018 ◽

Vol 11 (1) ◽

pp. 1 ◽

Cited By ~ 12

Author(s):

Dave Clarke ◽

Ajay Limaye ◽

Duane McKenna ◽

Rolf Oberprieler

Keyword(s):

New Species ◽

Light Microscopy ◽

Fossil Record ◽

Ct Scanning ◽

High Magnification ◽

New Genera ◽

Burmese Amber ◽

Critical Gap ◽

Selection Of

Only a few weevils have been described from Burmese amber, and although most have been misclassified, they show unusual and specialised characters unknown in extant weevils. In this paper, we present the results of a study of a much larger and more diverse selection of Burmese amber weevils. We prepared all amber blocks to maximise visibility of structures and examined these with high-magnification light microscopy as well as CT scanning (selected specimens). We redescribe most previously described taxa and describe 52 new species in 26 new genera, accompanied by photographs. We compare critical characters of these weevils with those of extant taxa and outline the effects of distortion on their preservation and interpretation. We conclude that only two weevil families are thus far represented in Burmese amber, Nemonychidae and a newly recognised family, Mesophyletidae, which appears closely related to Attelabidae but cannot be accommodated in this family. The geniculate antennae and long rostrum with exodont mandibles of most Mesophyletidae indicate that they were highly specialised phytophages of early angiosperms preserved in the amber, likely ovipositing in flowers or seeds. This weevil fauna appears to represent an extinct mid-Cretaceous ecosystem and fills a critical gap in the fossil record of weevils.

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