data analysis

Story behind the paper: Optimal stock-enhancement of a spatially distributed renewable resource

When the watering can principle is not a good idea to manage your ecosystem

Shape matters: the relationship between cell geometry and diversity in phytoplankton

We analyse data on marine unicellular phytoplankton, exhibiting an astounding diversity of cell sizes and shapes. We quantify the variation in size and shape and explore their effects on taxonomic diversity. We find that cells of intermediate volume exhibit the greatest shape variation, with shapes ranging from oblate to extremely elongated forms, while very small and large cells are mostly compact. We show that cell shape has a strong effect on phytoplankton diversity, comparable in magnitude to the effect of cell volume, with both traits explaining up to 92% of the variance in phytoplankton diversity. Species richness decays exponentially with cell elongation and displays a log-normal dependence on cell volume, peaking for compact cells of intermediate volume.

Power-law distribution in the number of confirmed COVID-19 cases

COVID-19 is an emerging respiratory infectious disease caused by the coronavirus SARS-CoV-2. It was first reported on in early December 2019 in Wuhan, China and within three months spread as a pandemic around the whole globe. Here, we study …

New Publication: Shape matters: cell geometry determines phytoplankton diversity

Exploring the shape-diversity relationship in phytoplankton

Long-term cyclic persistence in an experimental predator–prey system

Predator–prey cycles rank among the most fundamental concepts in ecology, are predicted by the simplest ecological models and enable, theoretically, the indefinite persistence of predator and prey. However, it remains an open question for how long cyclic dynamics can be self-sustained in real communities. Field observations have been restricted to a few cycle periods and experimental studies indicate that oscillations may be short-lived without external stabilizing factors. Here we performed microcosm experiments with a planktonic predator–prey system and repeatedly observed oscillatory time series of unprecedented length that persisted for up to around 50 cycles or approximately 300 predator generations.

New Publication in Nature: Long-term cyclic persistence in an experimental predator-prey system.

Realization of the longest known predator-prey time series

Length–volume relationship of lake phytoplankton

The shapes of phytoplankton units (unicellular organisms and colonies) are extremely diverse, and no unique relationship exists between their volume, V, and longest linear dimension, L. However, an approximate scaling between these parameters can be …

A periodic Markov model to formalize animal migration on a network

Regular, long-distance migrations of thousands of animal species have consequences for the ecosystems that they visit, modifying trophic interactions and transporting many non-pathogenic and pathogenic organisms. The spatial structure and dynamic …

The marine bacterium Phaeobacter inhibens secures external ammonium by rapid buildup of intracellular nitrogen stocks

Reduced nitrogen species are key nutrients for biological productivity in the oceans. Ammonium is often present in low and growth-limiting concentrations, albeit peaks occur during collapse of algal blooms or via input from deep sea upwelling and …

Biodiversity change is uncoupled from species richness trends: Consequences for conservation and monitoring

1. Global concern about human impact on biological diversity has triggered an intense research agenda on drivers and consequences of biodiversity change in parallel with international policy seeking to conserve biodiversity and associated ecosystem …