The interplay of nested biotic interactions and the abiotic environment regulates populations of a hypersymbiont

AbstractDespite the enticing discoveries of chaos in nature, triggers and drivers of this phenomenon remain a classical enigma which needs irrefutable empirical evidence. Here we analyze results of the yearlong replicated mesocosm experiment with multi-species plankton community that allowed revealing signs of chaos at different trophic levels in strictly controlled abiotic environment. In mesocosms without external stressors, we observed the “paradox of chaos” when biotic interactions (internal drivers) were acting as generators of internal abiotic triggers of complex plankton dynamics. Chaos was registered as episodes that vanished unpredictably or were substituted by complex behaviour of other candidates when longer time series were considered. Remarkably, episodes of chaos were detected even in the most abiotically stable conditions. We developed the Integral Chaos Indicator to validate the results of the Lyapunov exponent analysis. These findings are essential for modelling and forecasting behaviour of a variety of natural and other global systems.

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Evidence of plant– arthropod interaction in the fossil assemblage from Pitsidia (Messara Basin, Crete, Greece; Upper Miocene)

Neues Jahrbuch für Geologie und Paläontologie - Abhandlungen ◽

10.1127/njgpa/2020/0872 ◽

2020 ◽

Vol 295 (2) ◽

pp. 101-115

Author(s):

Giannis Zidianakis ◽

Johanna Kovar-Eder ◽

Avraam Zelilidis ◽

George Iliopoulos

Keyword(s):

Fossil Record ◽

Biotic Interactions ◽

Natural Ecosystems ◽

Ecological Functions ◽

Abiotic Environment ◽

The Past ◽

Plant Fossil ◽

Plant Assemblage ◽

Different Types ◽

Herbivore Community

As major components of natural ecosystems, plants interact with the biotic and abiotic environment developing a spectrum of different responses at various biological levels. Such biotic interactions are detectible in the plant fossil record and provide an outline of ecological functions during the past. The recently described Late Miocene plant assemblage from Pitsidia in the Messara Basin was examined for arthropod mediated damage. Most of the damage was detected on abundant, more than 2.500 specimens, well-preserved material of Myrica lignitum foliage, providing a broad range of traces. Eighteen different types of leaf modifications were distinguished, with hole, margin, surface feeding, lamina distortion and possibly galls as the most common while mining and exophytic oviposition were rare. Among this damage, it appears that only a few represent host-specialist feeding. These findings could serve as a database for the component herbivore community on M. lignitum. Considerations of this insect damage regarding past habitats and vegetation at Pitsidia as well as on plant–arthropod co-association are discussed. Several forms of arthropod damage on other plant taxa in this assemblage are briefly mentioned.

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The Evolution and Fossil History of Sensory Perception in Amniote Vertebrates

Annual Review of Earth and Planetary Sciences ◽

10.1146/annurev-earth-082517-010120 ◽

2018 ◽

Vol 46 (1) ◽

pp. 495-519 ◽

Cited By ~ 5

Author(s):

Johannes Müller ◽

Constanze Bickelmann ◽

Gabriela Sobral

Keyword(s):

Social Communication ◽

Biotic Interactions ◽

Sensory Perception ◽

Crucial Importance ◽

Abiotic Environment ◽

Definitive Evidence ◽

Sensory Evolution ◽

History Of ◽

Selection For ◽

Niche Competition

Sensory perception is of crucial importance for animals to interact with their biotic and abiotic environment. In amniotes, the clade including modern mammals (Synapsida), modern reptiles (Reptilia), and their fossil relatives, the evolution of sensory perception took place in a stepwise manner after amniotes appeared in the Carboniferous. Fossil evidence suggests that Paleozoic taxa had only a limited amount of sensory capacities relative to later forms, with the majority of more sophisticated types of sensing evolving during the Triassic and Jurassic. Alongside the evolution of improved sensory capacities, various types of social communication evolved across different groups. At present there is no definitive evidence for a relationship between sensory evolution and species diversification. It cannot be excluded, however, that selection for improved sensing was partially triggered by biotic interactions, e.g., in the context of niche competition, whereas ecospace expansion, especially during the Mesozoic, might also have played an important role.

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Ancient symbiosis confers desiccation resistance to stored grain pest beetles

10.1101/182725 ◽

2017 ◽

Author(s):

Tobias Engl ◽

Nadia Eberl ◽

Carla Gorse ◽

Theresa Krüger ◽

Thorsten H. P. Schmidt ◽

...

Keyword(s):

Biotic Interactions ◽

Desiccation Resistance ◽

Oryzaephilus Surinamensis ◽

Stored Grain ◽

Ecological Traits ◽

Abiotic Environment ◽

Dry Conditions ◽

Stored Grain Pest ◽

Microbial Symbionts ◽

Cuticle Thickness

AbstractMicrobial symbionts of insects provide a range of ecological traits to their hosts that are beneficial in the context of biotic interactions. However, little is known about insect symbiont-mediated adaptation to the abiotic environment, e.g. temperature and humidity. Here we report on an ancient (~400 Mya) clade of intracellular, bacteriome-located Bacteroidetes symbionts that are associated withgrain and wood pest beetles of the phylogenetically distant families Silvanidae and Bostrichidae. In the saw-toothed grain beetle Oryzaephilus surinamensis, we demonstrate that the symbionts affect cuticle thickness, melanization and hydrocarbon profile, enhancing desiccation resistance and thereby strongly improving fitness under dry conditions. Together with earlier observations on symbiont contributions to cuticle biosynthesis in weevils, our findings indicate that convergent acquisitions of bacterial mutualists represented key adaptations enabling diverse pest beetle groups to survive and proliferate under the low ambient humidities that characterize dry grain storage facilities.

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