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Articles 1 - 30 of 36
Full-Text Articles in Marine Biology
The Effect Of Post-Harvest Storage Temperature And Drying Method On The Pathogen Load Of Edible Kelp, Jessica Vorse
The Effect Of Post-Harvest Storage Temperature And Drying Method On The Pathogen Load Of Edible Kelp, Jessica Vorse
All Theses And Dissertations
The American seaweed industry is growing, primarily into the edible sector, and as a result, more seaweed products are available for human consumption. It is necessary to evaluate the safety of industry’s current post-harvest storage and processing methods to ensure the risk of foodborne pathogens on edible seaweed remains low. We evaluated the pathogen load of edible kelp post-harvest under three different storage temperatures (4˚C, 10˚C, 20˚C) and two different drying methods (air- and freeze-drying). The focal pathogens for this project were six of the most common food-associated pathogens in the United States: Listeria monocytogenes, Salmonella enterica, Staphylococcus aureus, pathogenic …
Climate-Driven Stock Shifts And Expansions In The U.S. Northeast Shelf: Identifying Challenges, Opportunities, And Barriers Through Fishermen And Manager Perspectives, Sophie A. Swetz
All Theses And Dissertations
Climate-driven warming in the U.S. Northeast Shelf (NES) has led to changes in the spatial distributions of many marine resources. Shifts and expansions of commercially important fish stocks pose major challenges to fishermen and fisheries managers in this region. American lobster (Homarus americanus) in the Gulf of Maine (GOM) is one of these impacted stocks and is projected to continue its shift towards more northern and offshore areas. Continued ocean warming could potentially reduce the GOM lobster stock by up to 60% over the next several decades. Given Maine’s reliance on its lobster fishery—which contributes over 80% of …
Possible Surf And Turf Mutualism: The Potential Of Yeast Grown From Maine Wood As Feed For Atlantic Salmon, Gina Scott
Possible Surf And Turf Mutualism: The Potential Of Yeast Grown From Maine Wood As Feed For Atlantic Salmon, Gina Scott
All Theses And Dissertations
With fed aquaculture expanding, challenges are being faced with increasing demands for protein for feed. Fishmeal as a protein is at high cost and low supply, and meals from terrestrial agriculture can impact fish health; both also generate environmental challenges. One potential alternative protein is yeast, which can be grown using waste softwood. Simultaneously, Maine forestry has lost buyers of waste wood with several paper mill closures. If yeast is produced as an alternative protein for fish feed using this wood, both Maine Atlantic salmon farming, Maine’s most valuable form of aquaculture, and Maine forestry could benefit. Environmental impact and …
The Waste Management Of Large-Scale Recirculating Aquaculture Systems And Potential Value-Added Products From The Waste Stream, Franco R. Pilone
The Waste Management Of Large-Scale Recirculating Aquaculture Systems And Potential Value-Added Products From The Waste Stream, Franco R. Pilone
All Theses And Dissertations
Recirculating Aquaculture Systems (RAS) is an emerging technology that is capturing the attention of many in aquaculture due to its ability to produce high-quality seafood using sustainable models. This study explored the waste management of RAS, specifically further treatment technologies, and the potential value-added products from the RAS waste stream that can be reused. Advanced, tertiary, or down-stream treatment technologies available for RAS were investigated through a literature review. Utilizing the constant comparative method and semistructured interviews with stakeholders in RAS, opinions and attitudes were collected about advanced treatment of RAS waste and reuse opportunities presented from value-added products generated …
Adding Value Through Sustainability: Incentivizing An Ecosystem Approach To Oyster Aquaculture In Maine, Samuel Feldman
Adding Value Through Sustainability: Incentivizing An Ecosystem Approach To Oyster Aquaculture In Maine, Samuel Feldman
All Theses And Dissertations
This study identified oyster farming practices that have the potential to increase the sustainability of Maine’s oyster industry while increasing its value. Practices aligned with the principles of the ecosystem approach to aquaculture were gleaned from semi-structured interviews and surveys of oyster farmers and their buyers. Themes from interview transcripts were developed using thematic analysis. Survey data was used to triangulate interview transcript data. As a result, sustainable oyster farming practices were identified that had direct and indirect connections to the value of Maine’s oysters. Practices with direct connections to increased oyster value included conducting and advertising actions of increased …
Investigating Larval Spillover From Oyster Aquaculture Through Geospatial Habitat Suitability Index Modeling: A Damariscotta River Estuary Case Study, Daniel F. Delago
Investigating Larval Spillover From Oyster Aquaculture Through Geospatial Habitat Suitability Index Modeling: A Damariscotta River Estuary Case Study, Daniel F. Delago
All Theses And Dissertations
The eastern oyster (Crassostrea virginica) supports the ecological function of estuarine ecosystems by creating biogenic reef habitat (Purchon, 2013), and positively influencing coastal biogeochemistry in intertidal, and subtidal environments (Humphries et al., 2016; Ray and Fulweiler, 2020). As anthropogenic impacts continue to influence the health of marine environments globally (Halpern et al., 2008), oyster reef restoration is gaining increased attention as a means of maintaining the function of estuarine systems (Beck et al, 2011). Shellfish aquaculture has gained increased attention, contributing 21% of all aquaculture production globally (FAO 2020). Shellfish aquaculture provides a suite of social-ecological benefits while …
Analyzing The Potential Of Bioelectrical Impedance Analysis In Identifying The Effects Of Freezing In Atlantic Sea Scallop Products (Placopecten Magellanicus), Joseph Ehrhard
All Theses And Dissertations
The sensitivity of bioelectrical impedance analysis (BIA) was investigated to assess the potential of identifying the effects of freezing in market-ready Atlantic sea scallops (Placopecten magellanicus). Measurements of resistance (R) and reactance (Xc) were recorded using a Certified Quality Reader (CQR) (Certified Quality Food Inc., Clinton Township, MI 48035) BIA device at 50kHz. Prior to investigating the effects of freezing on BIA measurements a standard operating procedure (SOP) was established to limit sources of error. BIA measurements were used in establishing an SOP which focused upon the preparation of samples through blot drying, as well as, proper orientation …
Adapting Biotoxin Monitoring For The Future: An Opportunity For A Harmful Algae Bloom (Hab) Network In Casco Bay, Maine, Zachary B. Gordon
Adapting Biotoxin Monitoring For The Future: An Opportunity For A Harmful Algae Bloom (Hab) Network In Casco Bay, Maine, Zachary B. Gordon
All Theses And Dissertations
Harmful Algae Blooms (HABs) related to marine biotoxins have considerable impacts on coastal communities and have been increasing in size and frequency globally. Maine is recognized as a leader in biotoxin management as it relates to bivalve shellfish, but it has been unclear how current management practices effect the growth of shellfish aquaculture and how they will adapt to future conditions. This research uses a collaborative approach to analyze the current state of biotoxin management in Maine. First, the current management practices in Maine were compared and contrasted with five other states dealing with similar issues. Then, the perspectives of …
Cultivating Cooperatives: Benefits And Challenges Of Co-Ops And Recommendations For Maine’S Emerging Aquaculture Industries, Phoebe Walsh
Cultivating Cooperatives: Benefits And Challenges Of Co-Ops And Recommendations For Maine’S Emerging Aquaculture Industries, Phoebe Walsh
All Theses And Dissertations
Two emerging Maine industries, kelp (Saccharina latissimi and Saccharina angustissima) and Atlantic sea scallop (Placopecten magellanicus) aquaculture, have enormous market, environmental, and social potential but are faced with challenges of small scale and limited operations, inadequate infrastructure, market visibility, and limited expertise. Because many industries, particularly the dairy industry, have benefited from the use of cooperatives (co-ops) to aggregate an extremely perishable product, quickly process and effectively market and distribute, this research explores the cooperative model as a potential tool for the nascent scallop and kelp industries. Aquaculture co-ops are new in Maine. The first, the …
Building Value Through Innovative Eucheuma Spp. Product Development: A Case Study With The Belize Women's Seaweed Farming Association, Bailey Moritz
Building Value Through Innovative Eucheuma Spp. Product Development: A Case Study With The Belize Women's Seaweed Farming Association, Bailey Moritz
All Theses And Dissertations
Seaweed aquaculture has been a successful supplemental livelihood in coastal communities worldwide, creating new income opportunities for women in particular. In most cases, raw or dried carrageenan-producing seaweed is sold into supply chains without local value addition taking place. Upgrading value chains can come in the form of new products, differentiation from existing products through marketing, or breaking into new markets. The research investigates the local market potential for value-added Belizean Eucheuma seaweed products and offers insights into a pathway forward for the Belize Women’s Seaweed Farming Association (BWSFA) to take advantage of these opportunities at an early stage of …
Can The Marsh Migrate? Factors Influencing The Growth Of Spartina Patens In Upland Soil, Tessa M. Dowling
Can The Marsh Migrate? Factors Influencing The Growth Of Spartina Patens In Upland Soil, Tessa M. Dowling
All Theses And Dissertations
Although high elevation salt marsh plants, such as Spartina patens (salt hay) can cope with accelerated sea level rise by migrating inland, it is not well known whether environmental factors, such as soil, plant litter, and salinity, will influence the ability of S. patens to colonize upland forest areas. For one growing season, I tested how S. patens vegetative growth (the final number of stems, aboveground stem biomass, and belowground rhizome biomass) and reproduction (presence of flowers) responded to upland or marsh soil, the presence or absence of plant litter, and 4.5ppt or 14.5ppt salinity levels. In order to determine …
Estimating The Post-Release Mortality Of Atlantic Cod (Gadus Morhua) In The Southern Gulf Of Maine Commercial Lobster Fishery, Brett Sweezey
Estimating The Post-Release Mortality Of Atlantic Cod (Gadus Morhua) In The Southern Gulf Of Maine Commercial Lobster Fishery, Brett Sweezey
All Theses And Dissertations
Atlantic cod, Gadus morhua, in the Gulf of Maine has experienced heightened fishing-induced mortality since the 1990s, leading to the lowest population abundances in recorded history. Unaccounted discard mortalities within Gulf of Maine commercial fisheries may be impairing recovery efforts in this and other cod populations. With over 4 million actively fished lobster traps, the Maine commercial lobster fishery has been suggested to be a significant contributor to cod mortality rates within this region. Therefore, the discard mortality rate of Atlantic cod captured by commercial lobster gear was examined to assess its potential influence on recovery efforts using acoustic …
Trophic Shifts Introduced To The Saco River Estuary By A Central Secondary Consumer, The Invasive European Green Crab (Carcinus Maenas), Andrew Paul Davidsohn
Trophic Shifts Introduced To The Saco River Estuary By A Central Secondary Consumer, The Invasive European Green Crab (Carcinus Maenas), Andrew Paul Davidsohn
All Theses And Dissertations
The European green crab (Carcinus maenus) is one of the most notorious invasive species found along the East coast of the United States. Green crabs were introduced to the US in the 1800s when they supposedly rode in ballast water across the Atlantic Ocean. Green crabs are native to the Atlantic coasts of Europe and Northern Africa. Once established on the Atlantic coast of North America, they started to migrate mostly north, and will continue to do so with warming waters due to climate change. (Glude 1955). Warmer winters will lead to greater crab egg survival, increasing the …
Examination Of Larval Transport, Distribution And Hybridization Patterns Of Two Blue Mussel Species Mytilus Edulis And M. Trossulus In Machias Bay, Maine, Elizabeth A. Prochaska
Examination Of Larval Transport, Distribution And Hybridization Patterns Of Two Blue Mussel Species Mytilus Edulis And M. Trossulus In Machias Bay, Maine, Elizabeth A. Prochaska
All Theses And Dissertations
Using an interdisciplinary approach, this study examined the population connectivity of the blue mussel Mytilus trossulus within Machias Bay, Maine, near its inshore southern boundary range. The Eastern Maine Coast Current (EMCC) flows southwestward along the northern Gulf of Maine coastline, just outside of Machias Bay and is a potential pathway for M. trossulus larvae. This study compared results to two historical studies that assayed M. trossulus and M. edulis species distributions to evaluate any temporal changes. Both similarities and differences were found in species composition in Machias Bay. Historical data suggested that the lower Machias Bay was supplied by …
Ichthyoplankton Distribution And Assemblage Within And Around The Saco River Plume, Tracey Bauer
Ichthyoplankton Distribution And Assemblage Within And Around The Saco River Plume, Tracey Bauer
All Theses And Dissertations
A majority of research has focused on the importance of large river plumes for ichthyoplankton survival and recruitment. However, the impacts of smaller, more ephemeral river plumes, such as those commonly found in the Gulf of Maine, on ichthyoplankton are far less understood. The purpose of the current study was to use a small river plume located in the southern Gulf of Maine as a model system to increase our understanding of their effects on ichthyoplankton distribution and diversity, and determine what biotic and abiotic factors may be influencing any differences observed. Plankton tow sampling revealed that although ichthyoplankton abundance …
The Effects Of Triiodothyronine, Glucose, Alanine, And Iodide As Nutrients On The Survival And Successful Metamorphosis Of Aeolidiella Stephanieae Veligers, Bryan Tate
All Theses And Dissertations
During early life stages, nutrients are crucial to the proper development of larval marine invertebrates. Many such larvae are lecithotrophic and therefore do not actively feed; however, a large body of research has shown that lecithotrophic larvae take in dissolved organic material (DOM) including amino acids and sugars, contributing heavily to metabolic requirements. Another dissolved nutrient, iodine, is useful to marine invertebrates for the production of organic compounds. Some of these compounds (thyroid hormones, THs) are historically thought to be used almost exclusively by vertebrates, though studies have shown that THs are also useful to some marine invertebrates for developmental …
Transport Regimes And Spread Of The Common Reed, Phramites Australis, In The Saco River, Me, Usa, Michelle A. Slater
Transport Regimes And Spread Of The Common Reed, Phramites Australis, In The Saco River, Me, Usa, Michelle A. Slater
All Theses And Dissertations
Allee effects are important to species invasions because population growth may be limited by low outcrossing potential in newly founded populations leading to depressed levels of fitness. Non-native Phragmites australis (common reed) has been present in the United States for over 200 years, but has been slow to reach some areas, possibly owing to the Allee phenomenon, whereby young or isolated Phragmites patches with initially low genotypic richness are slow to recruit viable seedlings due to inbreeding, which limits the rate of patch expansion. In order to explore the importance of the Allee effect in a recently invaded system, the …
Grey (Halichoerus Grypus) And Harbor Seal (Phoca Vitulina) Bycatch And Depredation In New England Sink-Gillnet Fisheries, Laura N. Sirak
Grey (Halichoerus Grypus) And Harbor Seal (Phoca Vitulina) Bycatch And Depredation In New England Sink-Gillnet Fisheries, Laura N. Sirak
All Theses And Dissertations
Marine mammals interact with commercial fisheries via competition for resources, depredation (feeding on fish caught in gear), entanglement, and bycatch in fishing gear. In New England, gray seals (Halichoerus grypus) and harbor seals (Phoca vitulina) are often taken as bycatch in sink-gillnet fisheries and are believed to depredate fish in gillnets. As seal populations increase, interactions with fisheries are also likely to increase, affecting both seal stocks and the New England fishing industry. This study aims to understand seal bycatch in the New England sink-gillnet fisheries by identifying the spatial and temporal trends in bycatch as …
Ion Regulatory Capabilities Of The European Green Crab, Carcinus Maenas, Exposed To Low Salinity Environments: An Investigation Into The Physiological Differences Between Two Color Morphs Across Sex, Anthony Himes
All Theses And Dissertations
The European green crab, Carcinus maenas, is a highly invasive species found throughout the world with severe economic and ecological impacts on the regions it invades. This species occurs in two color morphs: green after molting and red after prolonged intermolt. Physiological variations between these two morphs are well documented across various environmental conditions, but little work has focused on female C. maenas. To assess if the variation between color morphs observed in males persists in females, red and green morphs of each sex were exposed to a constant low salinity environment. Constant low salinity exposure was chosen as it …
Species Identification And Phylogeny Of Phycinae Hakes And Related Gadoid Fishes, Laura Ann Whitefleet-Smith
Species Identification And Phylogeny Of Phycinae Hakes And Related Gadoid Fishes, Laura Ann Whitefleet-Smith
All Theses And Dissertations
The term hake refers to a number of species belonging to multiple families of fish in the suborder Gadoidei and includes two main groups: Phycinae hakes (family Gadidae) and Merluccius spp. hakes (family Merlucciidae). The use of the common name hake for this diverse group of fish prompts questions such as: how are these species related and how can they be differentiated? Chapter one details the development of the Rapid Gadoid Identification Assay (RaGIA) for molecular identification of 11 gadoid fishes (including six hakes) using Polymerase Chain Reaction Restriction Fragment Length Polymorphism (PCR-RFLP). RaGIA was used for species identification of …
Application Of A Bioenergetics Framework For Assessing Sub-Lethal Effects Of Pollutants In The Freshwater Mussel Elliptio Complanata, Christopher G. Goodchild
Application Of A Bioenergetics Framework For Assessing Sub-Lethal Effects Of Pollutants In The Freshwater Mussel Elliptio Complanata, Christopher G. Goodchild
All Theses And Dissertations
Although biomarkers are frequently used to assess sublethal effects of contaminants, a lack of mechanistic linkages to higher-level effects limits the predictive power of biomarkers. Bioenergetics has been proposed as a framework for linking cellular effects to whole-animal effects. We investigated sublethal effects of exposure to wastewater treatment facility effluent in freshwater mussels in situ, thereby capturing ecologically relevant exposure conditions. Our study focused on the energetic biomarker AMP-activated protein kinase (AMPK), while also considering more traditional biomarkers like heat shock proteins (HSP70), and antioxidant enzymes (i.e., superoxide dismutase (SOD), glutathione-S-transferase (GST)). We examined biomarkers at mRNA and protein levels. …
The Saco River Plume: A Discussion Of The Near-Field Dynamics, Barbara A. Fortier
The Saco River Plume: A Discussion Of The Near-Field Dynamics, Barbara A. Fortier
All Theses And Dissertations
This study focused on the freshwater discharge plume from the Saco River in southwestern Maine to determine the mechanisms responsible for the largest impacts on the near-field dynamics in this region. We examined the forcing factors that tended to increase the plume's spatial extent upshelf of the river mouth. Salinity, temperature, and density data were collected during cruises from May through November 2010 and by two surface moorings deployed upshelf of the Saco River mouth. We found a distinct variation in the latitude of the upshelf boundary of the plume during and after periods of high discharge. Furthermore, we found …
East Coast Salt Marsh Response To Sea Level Rise: Microbial Community Function And Structure, Matt R. Simon
East Coast Salt Marsh Response To Sea Level Rise: Microbial Community Function And Structure, Matt R. Simon
All Theses And Dissertations
Coastal salt marshes are under stress from anthropogenic climate change-induced sea level rise (SLR). Sediment microbial decomposition is a major driver of marsh subsidence and any impact of SLR on this biotic process would have a direct effect on marsh surface elevation relative to sea level. Furthermore, sensitivity to SLR of microbial community composition may play a role in the functional response. I collected sediment from six coastal marshes on the United States Atlantic East coast, exposed it to simulated sea level rise and measured total respired carbon over a three week period. My results indicated that SLR caused a …
The Effect Of Ph On The Metal Binding Capabilities Of Exopolymeric Substances From A Marine Benthic Diatom, Vanessa O'Donnell
The Effect Of Ph On The Metal Binding Capabilities Of Exopolymeric Substances From A Marine Benthic Diatom, Vanessa O'Donnell
All Theses And Dissertations
The marine sediment-water interface is a dynamic microenvironment containing diatoms, which produce exopolymeric substance (EPS). EPS has various functions for individual cells and for marine ecosystems. EPS substance is a species-specific composition that has strong absorptive qualities and is able to bind metals from even a very dilute aqueous solution. As industrially derived metals tend to accumulate in marine mudflats, where diatoms are the major EPS producing organisms, it is important to determine how marine benthic diatom EPS will bind with metals. To address the metal binding properties of diatom EPS, Cylindrotheca closteriums’ EPS was isolated by tangential flow filtration, …
Validating The Use Of Sex Steroid Hormones Extracted From The Skeletal Muscle Tissue Of The Atlantic Sharpnose Shark (Rhizoprionodon Terraenovae), Spiny Dogfish (Squalus Acanthias), And The Little Skate (Leucoraja Erinacea) To Assess Reproductive Status In Elasmobranch Fishes, Bianca Prohaska
All Theses And Dissertations
Currently, circulating concentrations of plasma steroid hormones are used as one means to assess reproductive maturity and reproductive cycles in elasmobranchs. However, obtaining blood non-lethally from large and/or endangered species can be problematic because of difficulties involved with specimen handling. Thus, there is a need to develop new approaches and techniques to study the reproductive biology of elasmobranchs. Previous work conducted on other classes of vertebrates has demonstrated that steroid hormones can be successfully extracted from muscle tissue. The process of collecting muscle tissue samples is quick, minimally invasive, and may be conducted without removing the animal from the water, …
Assessing The Habitat Use, Diet, And Sex Ratios Of Atlantic (Acipenser Oxyrinchus) And Shortnose Sturgeon (Acipenser Brevirostrum) In The Saco River, Me, Caitlyn Little
All Theses And Dissertations
Due to the questionable status of sturgeon populations along the east coast of the United States, there has been considerable research focus on these species in recent years. Previous studies have overlooked the Saco River as an important habitat for sturgeon in the Gulf of Maine. However, the incidental capture of a sturgeon in the Saco River in the fall of 2007 raised questions about the presence of this species and the role that the Saco River might play in the life cycle of these fish. The goals of this thesis were to evaluate the utilization of this habitat by …
Consumptive And Non-Consumptive Effects Of Predatory Fishes On Lobster In Southern Maine, Erin B. Wilkinson
Consumptive And Non-Consumptive Effects Of Predatory Fishes On Lobster In Southern Maine, Erin B. Wilkinson
All Theses And Dissertations
The American lobster, Homarus americanus, is an important consumer in the Gulf of Maine benthic community and supports the most valuable fishery in New England. Many fish predators that feed on juvenile lobster are found in the Gulf of Maine, but their abundance has varied over the previous decades. For example, striped bass, Morone saxatilis, have recovered from near extinction to become a viable recreational fishery on the east coast, and previous work examining the gut contents of striped bass found that juvenile lobsters were a large component of their diet during the summer in Massachusetts. However, striped …
Assessing The Variability In Distribution Of Four Shark Species Within The Mississippi Sound, Daniel Crear
Assessing The Variability In Distribution Of Four Shark Species Within The Mississippi Sound, Daniel Crear
All Theses And Dissertations
Global declines in shark populations have been observed, including several species indigenous to the northwest Atlantic Ocean and the Gulf of Mexico (GOM). Attributing to these declines is a lack of abundance and distribution data of early life stages, particularly within essential habitats such as nursery grounds. Previous research has defined the Mississippi Sound as a multispecies shark nursery, therefore determining how abundance and distribution patterns change will aid in verifying where these species are throughout the year within this shark nursery. Thus, the objectives of the current study were to describe the variability in distributions of four shark species …
Two- And Three-Dimensional Photogrammetric Mass Estimation Techniques For Two Phocid Species: Halichoerus Grypus And Phoca Vitulina Concolor, Jennifer Harris
Two- And Three-Dimensional Photogrammetric Mass Estimation Techniques For Two Phocid Species: Halichoerus Grypus And Phoca Vitulina Concolor, Jennifer Harris
All Theses And Dissertations
Collecting mass measurements of seals is a common technique used to determine health. To determine the mass of Western North Atlantic Grey seal (Halichoerus grypus) and Atlantic Harbor seal (Phoca vitulina concolor) pups, a researcher must physically measure each animal. This produces stress for both pups and their mothers. Photogrammetric analysis (PGA) (evaluating photographs to obtain characteristics of a subject) has been used to determine physical measurements in a number of marine mammals. The purpose of this study was to develop a nonintrusive method for determining the mass of grey and harbor seal pups. Through this …
Invertebrate Zooid Polymorphism: Hydractinia Polyclina And Pagurus Longicarpus Interactions Mediated Through Spiralzooids, Charlotte M. Regula-Whitefield
Invertebrate Zooid Polymorphism: Hydractinia Polyclina And Pagurus Longicarpus Interactions Mediated Through Spiralzooids, Charlotte M. Regula-Whitefield
All Theses And Dissertations
Evaluating the net interaction between symbionts can be challenging when one participant is a colonial animal with polymorphic zooids, because each zooid type has unique functions. The colonial hydroid Hydractinia polyclina has three distinct zooid types, each of which contributes particular components to the interaction with host hermit crabs. Of these three zooid types, the function of spiralzooids is not well understood. Previously, spiralzooids have been proposed to contribute a strong negative interaction component by directly reducing their host hermit crab’s reproductive output. However, this hypothesis is not supported by past or current data. I propose that spiralzooids instead function …