The application of filtration theory to food gathering in Ordovician crinoids

2007 ◽  
Vol 81 (6) ◽  
pp. 1284-1300 ◽  
Author(s):  
James C. Brower
Keyword(s):  
Behavioral Changes ◽  
Filtration Theory ◽  
Upper Ordovician ◽  
Nutrient Contents ◽  
Particle Distributions ◽  
Wide Range ◽  
Ecological Patterns ◽  
Food Particles ◽  
Mean Size ◽  
Tube Feet

Food gathering of some adult Upper Ordovician crinoids was modeled by means of filtration theory. The arm-branching patterns of the 13 species examined range from nonpinnulate isotomous arms to uniserial and biserial arms with numerous pinnules. Most taxa are roughly equivalent with respect to ambient current velocities and the nutrient contents needed from seawater. Two species with extensively branched arms have markedly higher nutritional requirements at any one ambient current velocity. The results are somewhat correlated with environment in the form of differential current velocities, water flow patterns, and food abundance and composition. The data are generally compatible with filtration theory and the environmental distributions of many Ordovician and other Paleozoic crinoids, and they reveal that Upper Ordovician crinoids had at least partially developed the ecological patterns seen in later Paleozoic crinoids. Various morphological, physiological, and behavioral changes can be employed by crinoids to alter their nutritional balance. The size distributions of food particles that are caught by the crinoids are modeled. These food particle distributions for the Ordovician fossils resemble those of modern crinoids. Relative to the population of food items, the distributions of particles that are trapped are shifted towards larger items because the crinoid filtration nets are more efficient at catching larger particles. Crinoids with relatively open filtration nets and large food-catching tube feet are generalized and feed on a wide range of food particles of a relatively large mean size. The more specialized taxa with extensively branched arms bearing small and closely packed food-catching tube feet are restricted to a more narrow range of smaller food particles.

Paleoecology of suspension-feeding echinoderm assemblages from the Upper Ordovician (Katian, Shermanian) Walcott-Rust Quarry of New York

2011 ◽  
Vol 85 (2) ◽  
pp. 369-391 ◽  
Author(s):  
James C. Brower
Keyword(s):  
New York ◽  
Turbidity Currents ◽  
Maximum Height ◽  
Suspension Feeding ◽  
Upper Ordovician ◽  
Structure Comparison ◽  
Food Items ◽  
Wide Range ◽  
Soft Objects ◽  
Food Particles

The Walcott-Rust Quarry echinoderm fauna lived at the base of a carbonate ramp in moderately deep water (Benthic Assemblage 5 of Boucot and others) below wave base for all or most storms but within the photic zone. The inhabitants of the soft substrate were buried rapidly by distal carbonate turbidity currents or mudflows. Because of the episodic sedimentation, the organisms were opportunistic. The suspension-feeding echinoderms include nine crinoids, a rhombiferan, and a paracrinoid. They occur with a variety of filter-feeding bryozoan colonies, a few brachiopods, and numerous trilobites. Most suspension-feeding echinoderms were attached by small holdfasts to hard shelly substrates. Some of these substrates lay on the seafloor, whereas others may have been elevated when the larvae settled. Other types of holdfasts are distal stems that are tightly and permanently coiled around crinoid stems, open distal stem coils that lay on the substrate or were wrapped around soft objects, and recumbent stems running along the seafloor. The echinoderms occupied levels from the seafloor to almost a meter above it, whereas the bryozoans and brachiopods ranged from the seabed to a maximum height of about 10 cm. The sizes of the echinoderm food grooves and comparisons with their modern analogues along with filtration theory indicate that they ate food particles that were mostly larger than those taken by bryozoans. In general, the different taxa of suspension-feeding echinoderms living at the same elevation above the seafloor collected food particles of different maximum sizes and different mean sizes; however, they overlapped greatly with respect to smaller food items. The various crinoid species were able to feed at different ranges of ambient current velocities, which also tended to separate them ecologically. Crinoids having narrow food grooves were restricted to feeding on small food particles but they caught food items over a wide range of current velocities; the converse is also true, which suggests an evolutionary or behavioral tradeoff. As in most Ordovician crinoid communities, predation was comparatively low. Regenerated arms in crinoids reflect predation on about 1.8% of the individuals in the fauna and the most likely fossilized culprits are trilobites and straight nautiloids. Competition for space and attachment sites within and between species of the Walcott-Rust Quarry crinoid and rhombiferan assemblages does not seem to have been significant in regulating their ecological structure. Comparison with shallow-water crinoid assemblages of roughly the same age demonstrates that the Walcott-Rust Quarry faunas were less diverse and less complex. This could be caused by one or more of the following conditions that affected the Walcott-Rust fauna: lower average current velocities, the episodic sedimentological disturbances, higher suspended sediment content in the water, and softer substrates.

Systematics and paleoecology of Haptocrinus buttsi, a new species of disparid crinoid from the Upper Ordovician Hatter Limestone of central Pennsylvania

2008 ◽  
Vol 82 (3) ◽  
pp. 576-584
Author(s):  
James C. Brower
Keyword(s):  
New Species ◽  
Energy Budget ◽  
Current Velocity ◽  
Filtration Theory ◽  
Upper Ordovician ◽  
Central Pennsylvania ◽  
Food Particles ◽  
A New Species

Three crinoids are known from the Upper Ordovician Hatter Limestone at Union Furnace in central Pennsylvania, i.e., Haptocrinus buttsi n. sp., an unknown crinoid with a lichenocrinid holdfast, and an indeterminate columnal that probably belongs to a crinoid. Two crowns enable H. buttsi n. sp. to be reconstructed. The animal lived about 70 cm above the seafloor and was attached to a strophomenid brachiopod with a lichenocrinid holdfast. Its endotomous arms formed an efficient filtration net that covered much of the water within its planar filtration fan. The application of filtration theory indicates that H. buttsi n. sp. could begin to feed at a comparatively low ambient current velocity and balance its energy budget. Like many other ramulate disparids, H. buttsi n. sp. mainly collected moderately small food particles. As a member of the Tornatilicrinidae, H. buttsi n. sp. is a relatively primitive disparid. Another crinoid taxon bears a longer and thinner stem and a different type of lichenocrinid holdfast cemented to the same strophomenid shell. A third species, most likely a crinoid, is represented by a single columnal. The fauna lived in a quiet water lagoonal area, which is an unusual habitat for Paleozoic crinoids.

Some disparid crinoids from the Upper Ordovician (Shermanian) Walcott-Rust quarry of New York

2008 ◽  
Vol 82 (1) ◽  
pp. 57-77 ◽  
Author(s):  
James C. Brower
Keyword(s):  
New York ◽  
Deep Water ◽  
Upper Ordovician ◽  
Food Items ◽  
Wide Range ◽  
Food Particles ◽  
Anal Sac ◽  
Long Stem ◽  
Distal Stem

locrinus trentonensis Walcott, 1883 is characterized by the widest food grooves and the largest covering plates of any of the Walcott-Rust Quarry crinoids, which indicates that the animal captured relatively large food particles with large and widely separated tubefeet. Although iocrinids are generally considered as primitive disparids, their anal sac is unique. the holdfasts of I. trentonensis consist of distal stem coils that are tightly wrapped around the columns of other crinoids. the relatively long column of Ectenocrinus simplex (Hall, 1847) was attached to a wide range of shelly substrates by a small irregular and somewhat lobate holdfast. Ectenocrinids ate much smaller food items that were collected by smaller and more tightly packed tubefeet. the ontogeny of E. simplex illustrates the differences between the food gathering systems of conspecific crinoids from shallow and deep water habitats. the calceocrinid Calceocrinus barrandii Walcott, 1883 lived with its long stem forming a runner along the seafloor. the crown was movably hinged to the basal circlet and the stem. Moderately wide food grooves were probably present.

The Histology and Activities of the Tube-Feet of Antedon Bifida

1960 ◽  
Vol s3-101 (54) ◽  
pp. 105-117
Author(s):  
DAVID NICHOLS
Keyword(s):  
Hydrostatic Pressure ◽  
Basic Structure ◽  
Vascular Canal ◽  
Food Particles ◽  
Tube Feet

The histology of the tube-feet and adjacent parts of the water-vascular canal of the crinoid Antedon bifida is described. The tube-feet possess the same basic structure as other, better-known tube-feet; here, however, they are adapted to collect food particles. They shoot out mucus by means of special muscle-operated glands and bend rapidly inwards to waft the mucus with entrapped particles into the food-grooves. The protraction of the tube-feet is probably brought about by a mechanism very similar to the ampulla system, of other extensile tube-feet, but here the contraction of restricted portions of the water-vascular canal provides the necessary hydrostatic pressure.

scholarly journals A 15 million-year long record of phenotypic evolution in the heavily calcified coccolithophore <i>Helicosphaera</i> and its biogeochemical implications

2020 ◽  
Author(s):  
Luka Šupraha ◽  
Jorijntje Henderiks
Keyword(s):  
Cell Size ◽  
Resource Limitation ◽  
Tropical Indian Ocean ◽  
Adaptive Strategies ◽  
Cellular Level ◽  
Phenotypic Evolution ◽  
Environmental Forcing ◽  
Modern Species ◽  
Wide Range ◽  
Mean Size

Abstract. The biogeochemical performance of coccolithophores is defined by their overall abundance in the oceans, but also by a wide range in cell size, degree of calcification and carbon production rates between different species. Species’ sensitivity to environmental forcing has been suggested to relate to their cellular PIC : POC ratio and other physiological constraints. Understanding both the short and longer-term adaptive strategies of different coccolithophore lineages, and how these in turn shape the biogeochemical role of the group, is therefore crucial for modeling the ongoing changes in the global carbon cycle. Here we present data on the phenotypic evolution of a large and heavily-calcified genus Helicosphaera (order Zygodiscales) over the past 15 million years (Ma), at two deep-sea drill sites from the tropical Indian Ocean and temperate South Atlantic. The modern species Helicosphaera carteri, which displays eco-physiological adaptations in modern strains, was used to benchmark the use of its coccolith morphology as a physiological proxy in the fossil record. Our results show that, on the single-genotype level, coccolith morphology has no correlation with physiological traits in H. carteri. However, significant correlations of coccolith morphometric parameters with cell size and physiological rates do emerge once multiple genotypes or closely related lineages are pooled together. Using this insight, we interpret the phenotypic evolution in Helicosphaera as a global, resource limitation-driven selection for smaller cells, which appears to be a common adaptive trait among different coccolithophore lineages, from the warm and high-CO2 world of the middle Miocene to the cooler and low-CO2 conditions of the Pleistocene. However, despite a significant decrease in mean size, Helicosphaera kept relatively stable PIC : POC (as inferred from the coccolith aspect ratio) and thus highly conservative biogeochemical output on the cellular level. We argue that this supports its status as an obligate calcifier, like other large and heavily-calcified genera such as Calcidiscus and Coccolithus, and that other adaptive strategies, beyond size-adaptation, must support the persistent, albeit less abundant, occurrence of these taxa. This is in stark contrast with the ancestral lineage of Emiliania and Gephyrocapsa, which not only decreased in mean size but also displayed much higher phenotypic plasticity in degree of calcification while becoming globally more dominant in plankton communities.

Maturation thermique et histoire de l'enfouissement et de la génération des hydrocarbures du bassin de l'archipel de Mingan et de l'île d'Anticosti, Canada

1990 ◽  
Vol 27 (6) ◽  
pp. 731-741 ◽  
Author(s):  
Rudolf Bertrand
Keyword(s):  
Carbonate Platform ◽  
Burial History ◽  
Upper Ordovician ◽  
Southeastern Part ◽  
Middle Ordovician ◽  
Oil Generation ◽  
Wide Range ◽  
History Of ◽  
Anticosti Island ◽  
Depth Of Burial

Carbonate platform sequences of Anticosti Island and the Mingan Archipelago are Early Ordovician to Early Silurian in age. With the exception of the Macasty Formation, the sequences are impoverished in dispersed organic matter, which is chiefly composed of zooclasts. Zooclast reflectances suggest that the Upper Ordovician and Silurian sequences outcropping on Anticosti Island are entirely in the oil window but that the Lower to Middle Ordovician beds of the Mingan Archipelago and their stratigraphic equivalents in the subsurface of most of Anticosti Island belong to the condensate zone. Only the deeper sequences of the southwestern sector of Anticosti Island are in the diagenetic dry-gas zone. The maximum depth of burial of sequences below now-eroded Silurian to Devonian strata increases from 2.3 km on southwestern Anticosti Island to 4.5 km in the Mingan Archipelago. A late upwarp of the Precambrian basement likely allowed deeper erosion of the Paleozoic strata in the vicinity of the Mingan Archipelago than on Anticosti Island. Differential erosion resulted in a southwestern tilting of equal maturation surfaces. The Macasty Formation, the only source rock of the basin (total organic carbon generally > 3.5%, shows a wide range of thermal maturation levels (potential oil window to diagenetic dry gas). It can be inferred from the burial history of Anticosti Island sequences that oil generation began later but continued for a longer period of geologic time in the northeastern part than in the southeastern part of the island. Oil generation was entirely pre-Acadian in the southern and western parts of Anticosti Island, but pre- and post-Acadian in the northern and eastern parts.

Hybocrinid and disparid crinoids from the Middle Ordovician (Galena Group, Dunleith Formation) of northern Iowa and southern Minnesota

1992 ◽  
Vol 66 (6) ◽  
pp. 973-993 ◽  
Author(s):  
James C. Brower
Keyword(s):  
Multivariate Statistics ◽  
Supply Rate ◽  
Middle Ordovician ◽  
Crown Volume ◽  
Food Particles ◽  
Attachment Device ◽  
Short Covering ◽  
Tube Feet

Four hybocrinid and disparid crinoids from the Middle Ordovician Dunleith Formation (Galena Group) of northern Iowa and southern Minnesota are described: Hybocrinus conicus Billings, Ohiocrinus levorsoni n. sp., Caleidocrinus (Huxleyocrinus) gerki n. sp., and Ectenocrinus simplex (Hall). The first three taxa are rare. Ectenocrinus simplex is an abundant and protean form ranging from the Shermanian to the Maysville and from the Appalachians to the Midcontinent. One Middle Ordovician specimen from the Dunleith is a complete small adult with stem and a lichenocrinid holdfast. The column was largely upright with the crown located about 25 cm above the seafloor. The Middle Ordovician crinoids differ somewhat from the later Cincinnatian material where only young E. simplex exhibit lichenocrinid holdfasts. Older crinoids became detached and were eleutherozoic well before the column was 25 cm long. Thus, the Cincinnatian individuals lost the attachment device earlier during ontogeny than their ancestors in the Middle Ordovician. Unlike most associated crinoids, E. simplex formed a roughly conical filtration net. The arms of E. simplex are extensively branched. Ten main arms bear unbranched ramules on alternate brachials, and the arm structure converges on the pinnulate pattern. Narrow food grooves and short covering plates are present. Analogies with living crinoids indicate that small food particles were caught by small and close-spaced tube-feet. The formation of new plates and ramules at the arm tips increases the size of the food-gathering system throughout ontogeny. The food-gathering capacity comprises the number of food-catching tube-feet times the width of the food grooves, and it measures the number and size of food particles that can be caught. Both size and capacity of the food-gathering system are positively allometric compared to crown volume and the amount of tissue that must be nourished. This is mainly caused by the addition of new ramules at the arm tips, which generates an exponentially increasing plate supply rate. Examination of numerous specimens from various geographic and stratigraphic horizons with multivariate statistics shows that the species was homogeneous throughout its range aside from the differences in living habits mentioned above.

Cupulocrinid crinoids from the Middle Ordovician (Galena Group, Dunleith Formation) of northern Iowa and southern Minnesota

1992 ◽  
Vol 66 (1) ◽  
pp. 99-128 ◽  
Author(s):  
James C. Brower
Keyword(s):  
Niche Differentiation ◽  
Upper Ordovician ◽  
Average Width ◽  
Positive Allometry ◽  
Middle Ordovician ◽  
Surrogate Variable ◽  
Crown Volume ◽  
Food Particles ◽  
Anal Sac ◽  
Food Groove

Two cupulocrinids,Cupulocrinus crossmanin. sp. andPraecupulocrinus conjugans(Billings) n. gen., are known from the Middle Ordovician (Galena Group, Dunleith Formation) of northern Iowa and southern Minnesota. Various morphologic and ontogenetic features demonstrate thatPraecupulocrinusis more primitive thanCupulocrinus. The two species commonly occur together. In addition, both taxa coexisted at similar levels with stem lengths ranging from about 1.5 cm in juveniles to 15 cm in adults. Relatively complete growth sequences illustrate growth and variation and show how two related crinoids subdivided feeding niches. The crown volume provides a satisfactory surrogate variable for the size of the animal. The food-gathering system of the cupulocrinids is mainly augmented by the addition of new plates at the ends of the arms. The number of plates in the arms and the arm length exhibit positive allometry relative to crown volume, largely due to development of new branches at the arm tips. The food-gathering capacity equals the number of food-catching tube-feet multiplied by the average width of the food grooves. Food-gathering capacity is also positively allometric with respect to crown volume and the amount of tissue that must be supplied with food. Consequently, the ratio of food-gathering capacity:crown volume is either constant or declines slightly with increasing size and age. The food groove width increases throughout ontogeny so adult crinoids ate larger food particles than juveniles.Praecupulocrinus conjugans(Billings) n. gen. has more narrow food grooves thanCupulocrinus crossmanin. sp. of comparable size and age, which suggests niche differentiation based on food-particle size. The arm and tube-foot geometry indicates that both cupulocrinids utilized the same type of suspension feeding.The morphology of the anal sac and the lack of “patelloid” processes in the arms indicate thatCupulocrinus sepulchrumRamsbottom from the Upper Ordovician of Scotland belongs toDendrocrinus.

scholarly journals Changes of Nutrient Contents in Tomato Fruits Under The Influence of Increasing Intensity of Manganese Nutrition

2014 ◽  
Vol 21 (2) ◽  
pp. 297-307 ◽  
Author(s):  
Tomasz Kleiber
Keyword(s):  
Chemical Composition ◽  
Lycopersicon Esculentum ◽  
Plant Nutrition ◽  
Nutritive Value ◽  
Manganese Sulfate ◽  
Tomato Fruits ◽  
Nutrient Contents ◽  
Wide Range ◽  
Macro And Micronutrients ◽  
Manganese Nutrition

Abstract The aim of conducted in years 2008-2012 studies was to assess the efficiency of application of increasing manganese levels on the nutritive value of tomato fruits (Lycopersicon esculentum Mill. cvs. ‘Alboney F1’ and ‘Emotion F1’), expressed in the contents of macro- and micronutrients. Plants were grown in rockwool with application of nutrient solution characterized the following chemical composition (in [mg dm–3]): N-NH4 2.2, N-NO3 - 230, P - 50, K - 430, Ca - 145, Mg - 65, Cl - 35, S-SO4 - 120, Fe - 2.48, Zn - 0.50, Cu - 0.07, pH -5.50, EC - 3.00 mS cm–1. The following manganese plant nutrition levels were examined (in mg Mn · dm–3): 0.06 (control), 0.3, 0.6, 1.2 (Experiment I), 2.4, 4.8, 9.6 and 19.2 (Experiment II); (denoted as Mn-0, Mn-0.3, Mn-0.6, Mn-1.2, Mn-2.4, Mn-4.8, Mn-9.6; Mn-19.2). The source of manganese was manganese sulfate (MnSO4 · H2O, 32.3% Mn). The nutritive value of tomato fruits changed significantly under the influence of the application of wide range of manganese concentrations. It was found a significant reduction of the content of phosphorus (Exp. I, II), potassium (Exp. II), calcium (Exp. I, II) and magnesium (Exp. I, II). Manganese influence on the decreasing content of other metallic micronutrients (Fe, Zn, Cu) in fruits. Cultivar had a significantly influence on the content of: nitrogen (except Mn-2.4, Mn-4.8, Mn-9.6), potassium (in Exp. II, except Mn-4.8), calcium (except for Mn-0.6, Mn-2.4), magnesium (except Mn-0.3 and Mn-2.4), iron (except Mn-1.2), manganese and zinc (except control combination) and copper (except Mn-0.6 and Mn-1.2). The highest contents of N, Ca and Mg in fruits were recorded for the application of Mn-0, while for P and K - at 0.3 mg Mn dm–3, whereas it was lowest for all these nutrients (except N) in the case of Mn-19.2 (Exp. II). The reduction of nutrient contents amounted to (% changes: from the lowest content to the highest content): N (11.3), P (48.1), K (24.8), Ca (75.4), Mg (57.5), Fe (59.2), Zn (65.4) and Cu (43.7).

Different types of cirral activity of barnacles

1961 ◽  
Vol 243 (705) ◽  
pp. 271-307 ◽  
Keyword(s):  
Direct Observation ◽  
Laboratory Experiments ◽  
Full Range ◽  
Rhythmic Activity ◽  
Mantle Cavity ◽  
Body Fluids ◽  
Rhythmic Movements ◽  
Wide Range ◽  
Different Types ◽  
Food Particles

From direct observation and from cinematographic records five different types of cirral activity have been recognized in sessile barnacles. They are, arranged in increasing degree of muscular and cirral movement: (1) testing, in which the valves hardly open and the cirri are not protruded; (2) pumping, in which strong rhythmic movements of the operculum occur, but the cirri are protruded only slightly, and not extended; (3) normal beat, a development of pumping, but with the cirri fully extended and withdrawn in rhythm with the opercular movements; (4) fast beat, with less opercular movement, but strong and fast rhythmic cirral movements; (5) extension, in which the cirri are held outside the shell for varying periods without rhythmic movements. Stalked barnacles show simpler cirral activity, without regular rhythmic movements. The internal current which passes through the mantle cavity during normal beat and pumping in sessile species is considered to be primarily respiratory. The flow is shown to be sufficient for this purpose, and the energy expended in driving it through is calculated to be comparatively small. Further respiratory exchange of importance in fast beat and extension takes place via the larger cirri, which are distended and emptied of body fluids during cirral activity. In laboratory experiments under various conditions the balanoids alone showed the full range of movements. The Chthamalidae showed less rhythmic activity and no fast beat, while the stalked barnacles relied mainly on extension. These differences limit the habitats available to the latter groups, as compared with the Balanidae. Micro-feeding, with the smaller cirri used as a filter, can take place during pumping and normal beat, but is less efficient, to judge from rates of filtration, than captorial feeding on larger particles, when the larger cirri are employed. Fast beat is particularly well adapted to captorial feeding in still water, extension to captorial feeding in moving water. A wide range of food particles was found to be ingested, of sizes varying from a few microns to several millimetres; proteinaceous materials, such as planktonic animals and chopped lamellibranch muscle were most readily utilized, phytoplankton less so, while pure fats and starches passed unchanged through the gut. The interrelationship of cirral movements, feeding, and respiratory exchange is traced through the possible course of evolution of cirripedes, to the culmination in the most highly developed group, the Balanidae.

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