Search bioRxiv⌕ Search
Home/Archive/bioRxiv

bioRxiv · 10.1101/2024.10.02.616299

Influence of Shading on the Behavioral Ecology of a Caribbean Alcyonacean Octocoral, Briareum asbestinum, in the Florida Keys, United States

Draud, S. L.·Hoeksema, J. D.·Draud, M. J.
View original source ↗Export metadata ↓

Abstract

Using a restricted set of behavioral responses, corals must obtain sufficient light to maximize photosynthesis while simultaneously avoiding predation and molecular damage from UV radiation. This study investigates the polyp behavioral response of the Caribbean octocoral Briareum asbestinum to shading, and how this response influences reactions to a simulated predator cue. In experiment I, we measured changes in polyp extension before and after a shade structure was placed over colonies on a shallow patch reef in the Florida Keys. In experiment II, changes in polyp extension were measured following a simulated predator cue for both shaded and un-shaded colonies. Experiment I demonstrates that B. asbestinum possesses a mechanism for detecting changes in light intensity and responds by manipulating the extension of its polyps. Following polyp retraction due to a predator cue in experiment II, the temporal pattern of polyp re-extension differed between shaded and non-shaded colonies, and at the end of the observation period, shaded colonies had a greater proportion of extended polyps than non-shaded colonies, consistent with the results of experiment I. This research provides novel and valuable insights into the behavior of a common and important Caribbean octocoral and will serve as a foundation for future research pertaining to the physiological processes involved.

Explore related subjects

zoologyPreprint

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Draud, S. L., Hoeksema, J. D., Draud, M. J.. 2024-10-03. Influence of Shading on the Behavioral Ecology of a Caribbean Alcyonacean Octocoral, Briareum asbestinum, in the Florida Keys, United States. https://doi.org/10.1101/2024.10.02.616299

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

KEEP EXPLORING

Related preprints

bioRxiv2026

Bill colour outperforms iris colour for sexing in Starlings Sturnus vulgaris in breeding condition

Reliable morphological criteria for sexing birds without the need for invasive procedures are scientifically and ethically valuable. Smith et al (2005) reported that iris colour assigns the genetic sex of Starlings Sturnus vulgaris with 98% accuracy, and bill base colour with 100% accuracy when birds are in breeding condition, but these figures have not been tested independently. We applied their criteria to 31 captive Starlings in breeding condition, using three observers blind to genetic sex, two of them new to Starling sexing. Bill base colour correctly predicted genetic sex for all 29 birds scored, with complete observer agreement. Mean iris score was correct for 27 of 31 (87.1%), fewer than the 94 of 96 reported by Smith et al (2005) for birds in breeding condition (Fisher exact test, P = 0.031), although with so few errors in either study this comparison is imprecise. Observer agreement was high, so these errors reflect iris colouration conflicting with genetic sex rather than inconsistent scoring; bill base colour was correct for all four misassigned birds. Body mass and tarsus length classified 77% and 58% of birds correctly, their published thresholds missing in opposite directions. We conclude that bill base colour should be the primary criterion for sexing Starlings in breeding condition; the accuracy of iris colour should not be assumed to be 98%.

zoology↗
bioRxiv2026

Comparing the Influence of Habitat Configuration on Population Connectivity and Genetic Structure Using Congeneric Species Across Multiple Taxa

Abstract Habitat configuration influences population connectivity and, consequently, genetic structure. River networks provide heterogeneous, hierarchically arranged environments that shift drastically from upstream to downstream. We compared congeneric species across Ephemeroptera, Plecoptera, and Trichoptera, emphasizing longitudinal replacement (upstream to downstream) and the rarely studied wet rock (hygropetric) habitats. We surveyed six rivers on the Muroto Peninsula, Japan, qualitatively sampling aquatic insects at 63 sites. Cluster analysis based on the environmental data classified surveyed sites into four clusters. We analyzed a total of 10 species from four genera that exhibit longitudinal replacement patterns within genera. Genetic analyses based on the mitochondrial cytochrome c oxidase subunit I region revealed that upstream species showed higher genetic diversity than downstream species. In contrast, species adapted to hygropetric exhibited the lowest genetic differentiation among all habitat types. A novel contribution of this study is the inclusion of hygropetric species. The surprisingly low differentiation in hygropetric species suggests high connectivity, similar to lentic species. By comparing congeneric taxa across orders within environmentally similar rivers, we reduce phylogenetic and environmental confounds, strengthening inference that habitat configuration and dispersal traits jointly shape genetic structure. These findings provide a new perspective on riverine spatial ecology and underscore the importance of microhabitat-aware comparisons for evolutionary inference.

zoology↗
bioRxiv2026

Late lactation represents the main window for sow-to-piglet transmission of persistent gut strains

The gut microbiota plays a key role in piglet health, and maternal microbial transmission may represent a promising lever to shape early-life microbiota and prevent post-weaning digestive disorders. This study aimed to better characterize sow-to-piglet microbiota transmission and persistence using a long-read metabarcoding approach targeting the 16S-ITS-23S region. Fecal samples (n = 204) were collected from 17 families, a family being as sow and three of her piglets, at multiple stages: late gestation (G110), early (L6) and late lactation (L28) for sows; early lactation (L6), late lactation (L28), and 5 days post-weaning for piglets. To approximate strain-level resolution, a putative strain (PS) approach was developed by clustering ASVs (n = 6064) affiliated with the same species based on abundance covariance (r > 0.9), resulting in 4857 PS. Piglet microbiota progressively diversified during lactation and converged toward that of sow. In sows, 27 {+/-} 6% of PS were persistent from late gestation to late lactation. In piglets, only 4.2 {+/-} 2.5% of PS persisted from d6 to 5 days post-weaning. Persistent PS in piglets were mainly affiliated with Limosilactobacillus reuteri and Lactobacillus amylovorus followed with Holdemanella porci and H. biformis, Lentihominibacter hominis and Dorea formicigenerans. Shared PS were significantly higher within families than between unrelated pairs (p < 0.05). Maternal transmission peaked at the end of lactation (35 {+/-} 7% at L28). Persistent transmitted PS represented 2.7 {+/-} 1.6% (d6-post-weaning) and 15.4 {+/-} 5.6% (d28-post-weaning). Early-transmitted persistent PS were mainly affiliated with Limosilactobacillus reuteri, Lactobacillus amylovorus, and Paraeggerthella hominis, whereas late-transmitted persistent PS were associated with Prevotella spp., Sphaerochaeta globosa, and Bariatricus comes. These findings highlight the significance of maternal transmission in shaping the post-weaning microbiota and identify late lactation as a critical window for microbiota transfer.

zoology↗