Experimental results on larvae primed by turbulence and the effect on settlement size from Bodega Marine Lab in 2014 (Turbulence-spurred settlement project)

Website: https://www.bco-dmo.org/dataset/640538
Data Type: experimental
Version: 2016-03-15

Project
» Turbulence-spurred settlement: Deciphering a newly recognized class of larval response (Turbulence-spurred settlement)
ContributorsAffiliationRole
Gaylord, BrianUniversity of California-Davis (UC Davis-BML)Principal Investigator
Ferner, MatthewSan Francisco State University (SFSU)Co-Principal Investigator, Contact
Lowe, ChristopherStanford University - Hopkins (Stanford-HMS)Co-Principal Investigator
Copley, NancyWoods Hole Oceanographic Institution (WHOI BCO-DMO)BCO-DMO Data Manager


Dataset Description

Figure 8. Precompetent larvae primed by turbulence exposure settle at a smaller size. (a) Mean test area in 12-day-old juveniles (n=49) deriving from turbulence exposure (approx. 2 W kg−1 for 3 min) while precompetent, compared to 15-day-old competent juveniles (n =29) never exposed to turbulence. Shown are standard Tukey box plots with the dots as outliers. Representative 12-day-old turbulence-exposed juvenile (b) and 15-day-old control juvenile (c) from this experiment, photographed at the same magnification.
White dotted lines indicate the major and minor axes of the ellipses used to estimate cross-sectional test area. Note also the relatively shorter spines in (b), another indication of the precocious state of these turbulence-induced juveniles. Scale bars, 100μm. The effect size here (mean size on day 15−mean size on day 12) is 19 437 μm2.

See Hodin et al (2015) for full details.

Related Reference:
Hodin J, Ferner MC, Ng G, Lowe CJ, Gaylord B. 2015. Rethinking competence in marine life cycles: ontogenetic changes in the settlement response of sand dollar larvae exposed to turbulence. Royal Society Open Science. 2: 150114. doi: 10.1098/rsos.150114.

Related Datasets:
Turbulence settlement: fig.3
Turbulence settlement: fig.4-6_Batches A & B
Turbulence settlement: fig.4-6_Batch C
Turbulence settlement: fig.6b
Turbulence settlement: fig.7
Turbulence settlement: fig.8 bootstrap


Data Processing Description

BCO-DMO Processing:

- added conventional header with dataset name, PI name, version date, reference information
- renamed parameters to BCO-DMO standard
- replaced blank cells and hyphen with NA (not applicable) or nd (no data)


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Data Files

File
fig8a.csv
(Comma Separated Values (.csv), 6.56 KB)
MD5:dbb9b5cf2e1666845c43de67e5a6e943
Primary data file for dataset ID 640538

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Parameters

ParameterDescriptionUnits
setdescription of image: ruler; micrometer; 11-day juvenile with turbulence; 14-day juvenile with no turbulence unitless
num_juv_tmtidentification number of juvenile in treatment unitless
len1_umlength 1 of juvenile test micrometers
len2_umlength 2 of juvenile test micrometers
pixels1number of pixels for length 1 pixels
pixels2number of pixels for length 2 pixels
len1_mm_longlength 1 * 1000 (long format) millimeters
len2_mm_longlength 2 * 1000 (long format) millimeters
len1_mm_rndrounded length 1 millimeters
len2_mm_rndrounded length 2 millimeters
areaarea of juvenile test microns^2
um_per_pixelarea of juvenile test in pixels: (len1 /2)*(len2 /2)*PI pixels
commentcomment unitless


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Instruments

Dataset-specific Instrument Name
Generic Instrument Name
Camera
Dataset-specific Description
Leica (Solms, Germany) MC170 HD camera mounted on a Leica M125 dissecting microscope and a Leica DM1000 compound microscope
Generic Instrument Description
All types of photographic equipment including stills, video, film and digital systems.

Dataset-specific Instrument Name
Generic Instrument Name
Taylor–Couette system
Dataset-specific Description
To generate turbulence intensities (quantified in terms of the energy dissipation rate, in units of Wkg−1) ranging from those found in open ocean waters to those arising on wave-battered coasts, we employed a Taylor–Couette cell [29], an apparatus composed of two vertically oriented, coaxial cylinders separated by a 3.5mm gap that contains seawater (described in greater detail in [1]). We held the stationary inner cylinder, and thus the water in the gap, at 19–21◦C by means of a circulating water stream from a temperature-controlled water bath passing through the cylinder’s interior. During operation, the outer cylinder rotated at a prescribed speed causing relative motion between the cylinders and thereby shearing the seawater between them. At rotation speeds employed for testing sand dollar larvae, the sheared flow was turbulent [1]. [1]Gaylord B, Hodin J, Ferner MC. 2013 Turbulent shear spurs settlement in larval sea urchins. Proc. Natl Acad. Sci. USA 110, 6901–6906. (doi:10.1073/pnas. 1220680110)
Generic Instrument Description
An apparatus composed of two vertically oriented, coaxial cylinders separated by a gap that contains seawater. During operation, the outer cylinder rotates at a prescribed speed causing relative motion between the cylinders and thereby shearing the seawater between them.


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Deployments

Gaylord_Turb-Settlement

Website
Platform
lab Bodega Marine Laboratory
Start Date
2014-06-01
End Date
2014-08-31
Description
sand dollar settlement studies


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Project Information

Turbulence-spurred settlement: Deciphering a newly recognized class of larval response (Turbulence-spurred settlement)

Coverage: Northeast Pacific


Description from NSF award abstract:
With this award the investigators will explore a habitat-scale oceanographic process that has the potential to integrate studies of larval delivery with an understanding of how larvae respond to substrate-associated cues. This work will build on published and preliminary data indicating that turbulent shear characteristic of high-energy near shore environments primes larvae to initiate settlement and to transform into the juvenile stage. These prior findings suggest that: 1) Because turbulence intensity varies predictably as a function of the strength of wave breaking and other factors, turbulence could operate as an indicator for larvae of their approach to suitable habitat, providing a link between larger-scale dispersal phenomena, and near-bottom search and selection behaviors; and 2) The larval response to turbulence acts in an unprecedented fashion. In contrast to typical cues, turbulence does not induce settlement directly, but rather spurs otherwise "pre-competent" larvae that are refractory to chemical cues to become "competent", thereby causing them to acquire responsiveness to such cues and undergo settlement. The interdisciplinary team has combined expertise in larval biology, sensory ecology, and organism-flow interactions necessary to address this topic. They will employ a phylogenetically robust approach to explore the scope and adaptive significance of the turbulence response in a widespread and ecologically important class of organisms (echinoids; sea urchins and their relatives), and will determine whether the response is aligned with environmental conditions characteristic of these organisms' adult habitat. They will also test for ecologically important functional consequences of precocious, turbulence-induced settlement. This work will provide a detailed look at an entirely new class of settlement inducer, one with strong potential for changing current conceptualizations of dispersing larval stages, their ability to detect signatures of habitat across multiple scales, and the ways in which organism-level traits might influence population connectivity.

How organisms with dispersing life stages find their way back to adult habitat is a fundamental question in marine ecology. Considerable research has explored links between transport, delivery, settlement, and recruitment, with important advances in knowledge. However, a complete understanding of the larval recruitment process remains elusive. Standard tools for estimating dispersal (e.g., numerical circulation models) have limited spatial resolution, which prevents them from predicting at scales below a few hundred meters how larvae will interact with the shore. Studies investigating larval attachment have focused on chemical, tactile, or near-bottom hydrodynamic cues active across microns to centimeters. The novelty of the present project is that it will focus on processes at habitat scales -- between transport and settlement -- where there is a gap in the understanding of processes.

This project will provide a framework for integrating key concepts of propagule dispersal and settlement, two fundamental but largely disjunct themes in marine science. The understanding that will come from this study will provide key information for ecosystem based management of coastal marine resources. The investigators will develop a "Surfing to Settlement" virtual lab activity based on their research that will be incorporated into the VirtualUrchin web platform, a widely exploited educational resource at Stanford that gets thousands of unique users per month. Through connections to the San Francisco Bay National Estuarine Research Reserve, they will integrate the "Surfing to Settlement" activity into one of NERRs professional development workshops for central California educators, thus disseminating this resource to and gaining valuable feedback from dozens of teachers and thousands of students.



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Funding

Funding SourceAward
NSF Division of Ocean Sciences (NSF OCE)
NSF Division of Ocean Sciences (NSF OCE)
NSF Division of Ocean Sciences (NSF OCE)

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