User:Lbenedict/Siphonophorae/Bibliography

Annotated Bibliography, Lizzy

Dunn, C. W., Pugh, P. R., & Haddock, S. H. (2005). Molecular phylogenetics of the siphonophora (Cnidaria), with implications for the evolution of functional specialization. Systematic Biology, 54(6), 916–935. DOI:10.1080/10635150500354837


 * Describes the structure of siphonophores in depth, and also provides two possible evolutionary hypothesis for the diversity between species
 * Includes labeled diagrams that help with identifying structures
 * Zooids have specific functions that allow for processes such as feeding, defense mechanisms, locomotion and movement, excretion, and reproduction
 * Focused on the evolution of siphonophores, particularly if zooids have been gained or lost over the course of evolution
 * Were able to form conclusions about the appearance and evolution of certain traits
 * For example, they concluded that the short-stemmed morphology within the Codonophora has evolved multiple times
 * Generated phylogenetic trees describing the relationships between species
 * Evolutionary Hypotheses
 * 1. As time has gone on, there has been an increase in number of zooid types
 * 2. The last common ancestor had many types of zooids and the diversity seen today is due to loss of zooid types
 * The research done shows no evidence supporting hypothesis 1 and some evidence in support of hypothesis 2

Haddock, S. H. D., Dunn, C. W., Pugh, P. R., & Schnitzler, C. E. (2005). Bioluminescent and red-fluorescent lures in a deep-sea siphonophore. Science, 309(5732), 263. Retrieved from https://search.proquest.com/docview/213600804?accountid=9673


 * Think that siphonophores used bioluminescence as a mode of defense
 * Focused specifically on the genus Erenna to conduct their study
 * When young, the tentilla of organisms in the Erenna genus contain only bioluminescent tissue, but, as the organism ages, red fluorescent material is also present in these tissues
 * Also observed a unique flicking behavior that was associated with the tentilla
 * Concluded that Erenna uses their tentilla as a way to attract prey

Kuyper, D., Thibault, D., & Gibbons, M. J. (2020) Latitudinal changes in siphonophore assemblages across the Atlantic sector of the Southern Ocean. African Journal of Marine Science, 42(2), 209-219. DOI:10.2989/1814232X.2020.1774805


 * Due to their limited mobility, siphonophores can be used to help identify local oceanographic conditions throughout the ocean
 * Studied changes in diversity and abundance throughout different regions in the ocean
 * Data gathered showed that diversity was lowest in the Permanently Open Ocean Zone (POOZ), the Polar Frontal Zone (PFZ), and the Sub-Antarctic Zone (SAZ) and was high in the Sub-Tropical Convergence (STC); this means diversity increases when moving south to north
 * More siphonophores were captured in regions close to the Antarctic continent north, meaning abundance was high in these areas
 * The species present in abundance in the north and south varied from one another; these areas were found to have an average dissimilarity of 66.2%
 * 21 species were recorded, however, data was only taken to a depth of 300 meters
 * This is important because around Antarctica, some species have been observed at depths of 1000 meters, so this data is likely incomplete
 * Concluded that, in the Southern Ocean, factors such as chlorophyll concentration, surface temperature, surface salinity, and mixed layer depth impact siphonophore assemblages

Mapstone, G. (2014). Global diversity and review of Siphonophorae (Cnidaria: Hydrozoa). PloS one, 9(2), 1-37. DOI: 10.1371/journal.pone.0087737


 * This article covered many different topics regarding siphonophores, such as the history of their discovery, classification, and tentilla, but I chose to focus on the use of lures, a topic which has come up in multiple different articles I read
 * Thought this information could help supplement and provide updates to the article “Influence of siphonophore behavior upon their natural diets: evidence for aggressive mimicry”, which was written in 1980
 * As mentioned in the article by Purcell, Agalma okeni use their lure as a mimic device
 * Other siphonophores that use lures as a mimicry device include Athorybia rosacea, Athorybia lucida, Lychnafalma utricularia, and, due to their similar movements, possibly even Physophora hydrostatica
 * A. rosacea mimic fish larvae, A. lucida are thought to mimic larvacean houses, and L. utricularia mimic hydromedusa
 * Some siphonophores, specifically Resomia ornicephala uses light to attract prey
 * Though other species compete for the same food source, which is krill, R. ornicephala are thought to be successful in their hunting due to lures
 * The tentillum fluoresce green and blue
 * As mentioned in the article by Haddock, Erenna use red fluorescent lures
 * These lures attract prey, and it is thought that they might even be used to mimic a fish from the Cyclothone genus
 * I found this article particularly interesting because it mentioned many of the same organisms that I had seen throughout my other research

Pagès, F., Gili, J. (1991). Vertical distribution of epipelagic siphonophores at the confluence between Benguela waters and the Angola Current over 48 hours. Hydrobiologia, 216-217(1), 355-362. DOI:10.1007/BF00026486


 * Previous studies have found that the existence of boundaries between water masses has an impact on siphonophore migration
 * This study was performed off the coast of Namibia, as a distinct boundary is present there
 * Both temperature and salinity impacted vertical migration
 * Above 40 meters, most of the organisms were in an asexual stage, but below 40 meters, the organisms were found in both asexual and sexual stages
 * These results suggest that the less deep, warmer waters are more ideal for spawning
 * Of the species observed, the only ones found in both regions were C. appendiculata, S. gracilis, and A. okeni
 * This data suggests that that these are the only species to have migratory behavior
 * Seems as if C. appendiculata and A. okeni travelled to the surface at night, back lack of downward migration the next day suggests that they remained closer to the surface, with thermocline acting as a boundary
 * Concluded that vertical migration and differences are due to two populations, vertical migration by species such as C. appendiculata and A. okeni, and differences in patch size

Purcell J. E. (1980). Influence of siphonophore behavior upon their natural diets: evidence for aggressive mimicry. Science, 209(4460), 1045-1047. DOI:10.1126/science.209.4460.1045


 * Siphonophores are non-visual
 * They have adapted their feeding mechanisms in a way to both protect themselves from predators via avoidance and escape mechanisms, and to counteract the avoidance and escape mechanisms expressed in their prey
 * Diets varied between siphonophore species, and these differing diets were linked back to differing swimming behaviors
 * Strong swimming siphonophores with small gastrozooids feed primarily on small copepods
 * They change locations to encounter prey in higher densities
 * Weak swimming siphonophores with large gastrozooids feed on larger prey
 * Some species may attract prey by mimicking small zooplankton to attract both predators of and members of the organisms they are mimicking
 * This is sometimes done through the use of lures
 * However, siphonophores with large gastrozooids eat large prey, regardless of their swimming behaviors

Sutherland, K. R., Gemmell, B. J., Colin, S. P., & Costello, J. H. (2019). Propulsive design principles in a multi-jet siphonophore. Journal of Experimental Biology, 222(6), 1-8. DOI:10.1242/jeb.198242


 * The coordination of swimming units, called nectophores, on N. bijuga allow for many types of swimming, including forward and reverse, and help with DVM
 * Studied how the velum, a thin band of tissue around the get opening, influences swimming proficiency in N. bijuga
 * Found that the velum became smaller and more circular when the organisms were actually propelling forward and that the velum became larger during refill times
 * Velum positioning also changed from curving downward during jetting to moving inside the nectophore during refill
 * N. bijuga travelled further than expected from the refills, due to high-pressure

--

Annotated Bibliography (Antonia Israel R)

Haddock, Steven H. D., Dunn, Casey W., Pugh, Philip R., Schnitzler, Christine E. (2005). Bioluminescent and Red-Fluorescent Lures in a Deep-Sea Siphonophore. Science, vol. 309, p. 263. DOI: 10.1126/science.1110441


 * Most siphonophores are bioluminescent, and they often use this chemically-induced light as a defensive strategy against predators. Siphonophores are also effective predators themselves, yet they are extremely fragile.
 * Data was collected from three siphonophores belonging to the genus, Erenna, at depths between 1,600 - 2,300 meters. It revealed that Erenna feeds on fish, and researchers hypothesize that this non-visual species does so by emitting red-fluorescence in their tentilla along with a flicking pattern to lure fish.
 * There is a view that deep-sea organisms cannot detect long wavelengths (red light has a wavelength of 680 nm). If this is the case, then it is not possible for the fish to be lured by Erenna and there must be another explanation. However, the deep-sea remains largely unexplored and we should not discard red-light sensitivity.

Purcell, Jennifer E. (1980). Influence of Siphonophore Behavior upon Their Natural Diets: Evidence for Aggressive Mimicry. Science, vol. 209, pp. 1045-1047. DOI: 10.1126/science.209.4460.1045


 * The diets of siphonophore species within 11 genera were studied at depths between 0 - 25 m. In general, the diets of strong swimming species consist of small prey while the diets of weak swimming species consist of larger prey.
 * Strong swimmers change locations often in order to encounter high-density prey.
 * Weak swimmers are relatively inactive, lowering their chances of encountering prey while simultaneously saving energy.
 * Species with large gastrozooids consume a broad range of prey sizes.
 * To capture prey, siphonophores use their tentacles as “webs” that prey swim into. Within the tentacles, there are millions of toxic nematocysts (specialized cells in the tentilla) that sting and paralyze their prey.
 * Two siphonophore species attract relatively large prey by mimicking small zooplankton. These species possess nematocyst batteries that help deceive and poison the prey.

Palma, Sergio, Cabello, Fabiola, Silva, Nelson, Canepa, Antonio (2017). Siphonophores of the Chiloé Inland Sea: biodiversity, spatial distribution, and environmental association. Marine Biodiversity vol. 48, pp. 1731-1742. DOI: 10.1007/s12526-017-0662-y.


 * For this study, nine siphonophore species were identified in the Chiloé Inland Sea. The purpose was to study their abundance, distribution, and ecological impact in the area.
 * In general, siphonophore densities are most concentrated in the north micro basin, which contains estuarine waters (which according to the text consist of “greater vertical stratification, lower temperatures and salinity, and a higher concentration of dissolved oxygen”) at depths of 0 - 50 m. In the south micro basin, they are mostly found at depths > 50 m.
 * Siphonophores are predators with important ecological roles. According to the text, they consume a wide range of prey including zooplankton, which may be of commercial interest. As an example, Muggiaea atlantica has negative effects on salmon farming.
 * In Chile, siphonophores have been studied extensively in regards to their taxonomy and the distribution of the most abundant and the most ecologically important species. 55 out of 175 siphonophore species have been observed along the Chilean coast, and 15 have been observed in the Chiloé Inland Sea.

Araya, Juan Francisco, Aliaga, Juan Antonio, Esther Araya, Marta (2016). On the distribution of Physalia physalis (Hydrozoa: Physaliidae) in Chile. Marine Biodiversity vol. 46 pp. 731-735. DOI: 10.1007/s12526-015-0417-6


 * Several colonies of Physalia physalis, otherwise known as the Portuguese Man o’ War, washed ashore in the Atacama Region of Chile in 2015. This abundance likely occurred due to El Niño Southern Oscillation events, and it incentivized a study of the species based on new findings.
 * This species is mostly found in tropical and subtropical regions, where the ocean is warm.
 * Physalia physalis is almost transparent, it floats in the surface of the ocean because of its air bladder, and it is able to navigate because of its erectile sailing crest. This species has thin tentacles, dactylozooids, that according to the text are “capable of discharging thousands of cnidae, which depend on mechanical and chemical stimuli, producing acute envenoming in humans and even death caused by vasomotor dysfunction and collapse”.

Costello, John H., Colin, Sean P., Gemmell, Brad J., Dabiri, John O., Sutherland, Kelly R. (2015). Multi-jet propulsion organized by clonal development in a colonial siphonophore. Nature Communications, vol. 6, 8185. DOI: 10.1038/ncomms9158


 * Siphonophores are unique in the sense that they are made up of clonal individuals, or nectophores, that form by budding and are genetically equal. Nectophores join in a complex aggregate colony organization.
 * For this study, the nectophores of the species Nanomia bijuga were observed. In general, young and weak nectophores “dominate torque production for turning” while older and more powerful nectophores “contribute predominantly to forward thrust production”. Every individual is key to the movement of the aggregate colony, and understanding their organization may allow us to make advances in our own multi-jet propulsion vehicles.
 * The nectophores of Nanomia bijuga allow for the species to swim forwards and reverse, to spiral and contract, and to swim in many other complex ways. Nanomia bijuga practices vertical migration every day, as it remains in the deep during the day but rises during the night.
 * According to this text, the aggregate colony organization of siphonophores is an evolutionary advantage. It has allowed for the organism to grow extensively. Additionally, if and when individual nectophores suffer damage, their role is bypassed by other nectophores (even when every nectophore - weak or powerful - is essential to the mechanism of swimming).

Mapstone, Gillian M. (2014). Global Diversity and Review of Siphonophorae (Cnidaria: Hydrozoa). Public Library of Science, vol. 9, 2. DOI: 10.1371/journal.pone.0087737


 * This 37-page paper is a summary of the history of siphonophores. The author aims to cover the first discovery of siphonophores in 1785 (Physalia physalis) until the most recent findings, which includes their overall distribution, abundance, and body-plans (e.g. their tentilla can incorporate toxic nematocysts and/or serve as lures that emit red-fluorescence).
 * There is no fossil record of siphonophores, even when they have evolved and developed for an extensive period (its phylum, Cnidaria, dates back to 640 million years).
 * Smaller species live in the epipelagic zone where they mostly feed on zooplankton, while larger species live in the mesopelagic zone where they mostly feed on larger prey. They hunt by casting “webs” with their tentacles that essentially traps and poisons prey.
 * 91% of siphonophores are bioluminescent, though most use this for defensive purposes. However, the tentilla of some larger deep-sea siphonophores emit bioluminescence. This light attracts prey as it may resemble smaller organisms such as zooplankton and copepods. For example, the species Erenna resides between 1600 - 2300 m, and it has adapted in a way that allows it to produce red-fluorescence in a rhythmic pattern that attracts deep-sea fish.
 * This paper includes a variety of pictures, diagrams, charts and phylogenetic trees that are useful to further understand the nature of siphonophores.

Annotated Bibliography (Joshua Kim)


 * 1) Damian-Serrano, A., Haddock, S. H., & Dunn, C. W. (2020). Shaped to Kill: The Evolution of Siphonophore Tentilla for Specialized Prey Capture. BioRxiv; Cold Spring Harbor, Volume (Version 1), doi: http://dx.doi.org/10.1101/653345

-Evolution has made it so that there are organisms that all are functional parts in one big system (siphonophore)

-Living in the pelagic zone, siphonophores catch prey using netlike tentacles with venomous cells in the tentacle net

-The morphology of the siphonophore depends on the type of prey they feed on

-Study was done to test morphology of tentacles and analyze evolutionary relationships in morphology

-Evolution is important to see how these siphonophores evolved around their prey’s evolutions and how evolution may rely on the food web


 * 1) Kuyper, D., Thibault, D., Gibbons, MJ. (2020). Latitudinal changes in siphonophore assemblages across the Atlantic sector of the Southern Ocean. African Journal of Marine Science; Grahamstown, Volume 42, 209-219, doi: http://dx.doi.org/10.2989/1814232X.2020.1774805

-Taking a look at old samples collected in 1993 near SANAE in Antarctica

-Results on structure were influenced by too many factors

-Using siphonophores can help measure water mass and movement, but it has not been used yet

-The taxon could represent something else so the study was inconclusive

-The study shows that old samples of plankton could still be useful today


 * 1) Madinand L.P., Harbison G.R.(2001). Gelatinous Zooplankton. Encyclopedia of Ocean Sciences, Volume (Second Edition), 9-19, doi: https://doi.org/10.1016/B978-012374473-9.00198-3

-After study of four seasons in the Algerian coast, it was found that spring brought the most diversity and most organism abundance during the warmer seasons

-Gelatinous zooplankton that are mostly made of water

-Organisms from many different phyla evolved independently to become zooplankton

-The diversity of gelatinous zooplankton shows that they all evolved in similar environments

-The gelatinous body plan was a good evolutionary tactic because it allowed for flexibility when catching prey

-Gelatinous adaptations are based on habitat


 * 1) Pugh, Philip R. (2014). Siphonophora. AccessScience, doi: https://doi.org/10.1036/1097-8542.625800

-siphonophores are complex animals that come in colonies

-their individual components are diverse which make their overall survival dependent on each other in the colony

-They do not exhibit alternation of generations like most other hydrozoans but instead bud off to reproduce

-Most siphonophores live in water and there are three major types: cystonects, physonects, and calycophorans (recent studies have found that it is more complicated than subjecting them into three separate types)


 * 1) T. D. O’Hara, Williams, A, Ahyong, S T, Alderslade, P, Alvestad, T. (2020) et al.Marine Biodiversity Records. London, Volume. 13, 1-27. doi:10.1186/s41200-020-00194-1

-Collections of specimen of the sea floor in eastern Australia has proved to help with further research

-Study done to collect samples from 2500-4000 m in depth around the western boundary of Tasman Sea

-Got 25,710 specimen and were only able to describe 42% of the collected samples

-The results will help start for future research ecologically, biogeographically, phylogenetically, and taxonomically