bioRxiv Science⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2023.05.31.543056

Growth dynamics and genetic variation in attached and free-living populations of the filamentous brown seaweed, Pilayella littoralis

Miller, S. L.·Wilce, R. T.
View original source ↗Export metadata ↓

Abstract

We used common garden growth experiments to study genetic variation among geographic isolates (Greenland, Massachusetts, and Connecticut, USA) of the filamentous brown seaweed Pilayella littoralis, including the free-living form unique to Nahant Bay, Massachusetts. Ecotypic variation for temperature growth maximum was demonstrated for a west Greenland isolate (10{degrees} C versus 15{degrees} C for other attached isolates) and between Nahant Bay attached (narrower phenotypic plasticity) and free-living forms (broader phenotypic plasticity) of the species. Morphological and reproductive characteristics of attached and free-living isolates remained distinctive under identical culture conditions after four years. The attached forms were characteristically cabled, twisted, and clumped; unilocular reproductive cells were common and plurilocular reproductive cells were present. The free-living form was characteristically loosely branched and ball-like; only vegetative reproduction occurred, with a few unilocular reproductive cells observed in one experiment. Free-living and attached isolates cultured using no water movement and turbulent conditions to mimic surf and surge conditions did not develop forms that resembled each other after eight months. We additionally used starch gel electrophoresis to study genetic variability in attached and free-living forms of P. littoralis from Nahant Bay. Free-living and attached populations were not different at the isozyme level because a limited number of isozymes were resolved (six out of 39 enzymes tested). One isozyme (PGI) was polymorphic, with two alleles present. The two alleles shared in the attached and free-living populations suggest that the free-living form is not one large identical clone. For attached and free-living P. littoralis, both transplant and growth studies in the laboratory provide convincing evidence of ecotypic differentiation.

Explore related subjects

ecologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Miller, S. L., Wilce, R. T.. 2023-06-04. Growth dynamics and genetic variation in attached and free-living populations of the filamentous brown seaweed, Pilayella littoralis. https://doi.org/10.1101/2023.05.31.543056

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related preprints

bioRxiv2026

Operationalising the context in regenerative agriculture: decision-making and farm variability

Soil degradation is a widespread challenge that requires a broad response at the individual farm level. To ensure effectivity, the practices should be tailored to the farm context: land manager objectives and farm specific challenges. These have however been difficult to quantify. Here we demonstrate that a workable farm context can be created based on a value survey, open satellite and soil data, and published models for vegetation gross primary productivity and soil erosion. Based on the findings, despite individual differences, farmers value profitability and operational efficiency, but also biodiversity and soil health. At least the regenerative farmers surveyed also value working for the greater good more than maintaining tradition or power. In spite of wide differences in farm production orientation, we also found that each farm also had a broad variation in individual fields GPP. Most fields have a stable GPP level, which is either high or low, and that there is a 2-3-fold difference between the weakest and best producing fields indicating the potential for improving GPP by improving the growing conditions on currently weak fields. In addition, soil loss was found to be highly concentrated in critical source areas, where 10% of the field area contributed to 50% of the soil loss. Overall, open data can be linked to modelling workflows to rapidly produce a decision-making context for farmers. This facilitates benchmarking and co-learning as well as enables land managers and advisors to identify the farm context for planning effective responses to soil degradation.

ecology↗
bioRxiv2026

Fly, land, listen: Autonomous intermittent locomotion enables scalable low-noise drone ecoacoustic surveys

Ecoacoustic monitoring is enabling scientists and land managers to monitor and manage biodiversity more effectively and cost-efficiently in the face of human pressures and rapidly changing climates. Currently, most ecoacoustic surveys use manually deployed static sensors to record data, limiting the scale and reach of surveying efforts. Here we present a proof-of-concept autonomous drone platform that can use intermittent locomotion to conduct ecoacoustic surveys using an onboard sensor. Our custom prototype is able to fly, navigate, and avoid obstacles autonomously, land at a pre-determined location, record audio from an onboard microphone whilst static, before taking off and moving to the next sampling site. Autonomous navigation and operation enable greater sampling flexibility, reach, and scalability. Furthermore, by recording audio only whilst landed, noise from the drone's rotors does not mask signals or disturb animals, simplifying signal processing and downstream ecological analyses. We conducted trials in a scrubland habitat at the Knepp Estate in West Sussex, where our prototype demonstrated successful autonomous navigation and obstacle avoidance. Furthermore, we found that avian biodiversity data collected from the drone platform was comparable to that from traditional static acoustic sensor deployments, and that vocalisation patterns were not significantly impacted by the noise of the drone arriving or leaving a site. While scaled deployments of our technology would require further technical and regulatory challenges to be solved, our first demonstration of autonomous intermittent robotics-assisted ecoacoustic surveys lays the foundations for more cost-effective and far-reaching biodiversity surveys, with transformative potential for conservation, agricultural management, biosecurity, and more.

ecology↗
bioRxiv2026

Do higher-order moments improve inference of population dynamics?

Fitting mathematical models of population dynamics to microbial time-series data allows us to estimate the ecological processes and interactions taking place in the microbiome. Repeated experiments of microbial systems yield replicates which slightly differ from each other. Some of this variability arises due to the fact that births and deaths occur at random. Most prior work focuses on fitting a deterministic mathematical model to the average across replicates. We use a stochastic model to fit the variability to the observed variability across replicates. Using a simulation-driven approach, we study the conditions under which our approach allows us to infer a larger fraction of ecological parameters correctly. We observe a substantial improvement in parameter inference. Lastly, our Bayesian approach not only allows us to incorporate prior information about the system, but also provides a distribution of parameters which conveys some idea of the uncertainty of the estimates.

ecology↗