Development of the pharyngeal dentition of two herbivorous halfbeaks (Teleostei : Hemiramphidae) and implications for the hemiramphid ontogenetic trophic shift

2008 ◽  
Vol 59 (2) ◽  
pp. 117 ◽  
Author(s):  
Ian R. Tibbetts ◽  
Ryan D. Day ◽  
Lee Carseldine
Keyword(s):  
Standard Length ◽  
Plant Material ◽  
Tooth Wear ◽  
Pharyngeal Tooth ◽  
Wear Area ◽  
Ecological Implications ◽  
Trophic Shift ◽  
Tooth Number ◽  
Almost All

Development of the pharyngeal dentition of two herbivorous halfbeaks, Hyporhamphus regularis ardelio (Whitley, 1931) and Arrhamphus sclerolepis krefftii (Steindachner, 1867), was examined quantitatively to assess features that might confer their ability to shift their diet from animal to plant material. Toothed area, tooth number, maximum tooth diameter and tooth wear area in both pharyngeal tooth pads of both taxa increased with ontogeny, whereas tooth density decreased. Comparing individuals of the two taxa at similar standard lengths indicated that A. sclerolepis krefftii showed hypertrophy of the majority of pharyngeal characters in relation to H. regularis ardelio of a similar standard length. That A. sclerolepis krefftii is more developmentally advanced than H. regularis ardelio in almost all dentigerous characters studied indicates that pharyngeal development may allow the former to commence herbivory at a smaller standard length than the latter species. The evolutionary and ecological implications of these findings are discussed in the context of a group of fishes that is overexploited worldwide.

Wood anatomy of the Mascarene Dombeyoideae: Systematic and ecological implications

IAWA Journal ◽  
2011 ◽  
Vol 32 (4) ◽  
pp. 493-519 ◽  
Author(s):  
Anaïs Boura ◽  
Timothée Le Péchon ◽  
Romain Thomas
Keyword(s):  
Evolutionary History ◽  
Wood Anatomy ◽  
Sister Group ◽  
Biological Data ◽  
Sister Group Relationship ◽  
Anatomical Features ◽  
Ecological Implications ◽  
History Of ◽  
Mascarene Islands ◽  
Almost All

The Dombeyoideae (Malvaceae) are one of the most diversified groups of plants in the Mascarene Islands. Species of Dombeya Cav., Ruizia Cav. and Trochetia DC. are distributed in almost all parts of the archipelago and show a wide diversity in their growth forms. This study provides the first wood anatomical descriptions of 17 out of the 22 Mascarene species of Dombeyoideae. Their wood anatomy is similar to that of previously described species: wide vessels, presence of both apotracheal and paratracheal parenchyma, and storied structure. In addition, we also found a second wood anatomical pattern with narrower vessels, high vessel frequency and thick-walled fibres. The two aforementioned wood patterns are considered in a phylogenetic context and used to trace the evolutionary history of several wood anatomical features. For example, the pseudoscalariform pit arrangement supports a sister group relationship between Trochetia granulata Cordem. and T. blackburniana Bojer ex Baker and may be a new synapomorphy of the genus Trochetia. Finally, wood variability is evaluated in relation to geographic, climatic and biological data. Despite the juvenile nature of some of the specimens studied, we discuss how the habit, but also factors related to humidity, influence the variability observed in the Mascarene Dombeyoideae wood structure.

Variation in the long-tailed field-mouse ( Apodemus sylvaticus (L.)) in the Channel Islands

1967 ◽  
Vol 166 (1005) ◽  
pp. 408-421 ◽  
Keyword(s):  
General Pattern ◽  
Tooth Wear ◽  
Foramen Magnum ◽  
Apodemus Sylvaticus ◽  
Channel Islands ◽  
Southern England ◽  
Channel Island ◽  
Canonical Variates ◽  
Pattern Of Variation ◽  
Almost All

Measurements of ten skull characters were made on each of 352 specimens of Apodemus sylvaticus (L.) and 37 specimens of A. flavicollis (Melch.). The latter were obtained from southern England and the former from five of the Channel Islands, two localities in southern England and one in northern France. The characters were greatest length, greatest width, interorbital breadth, cranial breadth, width of foramen magnum, length of maxillary tooth row, length of palatal foramen, distance between ventro-posterior processes of pterygoids, length of mesopterygoid fossa and minimum distance between first upper molars. The ages of the skulls were ascertained by means of a tooth-wear measurement. A regression adjustment was used to bring all the characters to a uniform age class. The sexes were separate throughout the analyses. The unadjusted and adjusted means have been calculated of each character for every locality. Appreciable variation occurs between the populations examined, with the females slightly smaller than the males but following the same general pattern of variation. An analysis into canonical variates was made with a view to accounting for the largest possible part of the variation between groups using a limited number of linear combinations of the original measurements. Almost all the variance was contained in the first four canonical variates and from these it appeared that the populations separated into three groups. The first contained the mainland mice from Hampshire, Cornwall and Cap Gris Nez, the second those from the Channel Islands and the third the collection of A. flavicollis. The analysis confirms that in the British Isles A. flavicollis is distinct from A. sylvaticus and that the Channel Island mice, although larger than the mainland A. sylvaticus , probably belong to that species. Differences between populations from the Channel Islands are small, although the mice from Herm and Sark are relatively large. It is possible that the Channel Island mice could have been derived from a common stock.

Trophic shifts in three subtropical Australian halfbeaks (Teleostei:Hemiramphidae)

2005 ◽  
Vol 56 (6) ◽  
pp. 925 ◽  
Author(s):  
Ian R. Tibbetts ◽  
Lee Carseldine
Keyword(s):  
Standard Length ◽  
Trophic Status ◽  
Marine Species ◽  
Filamentous Algae ◽  
Ontogenetic Shift ◽  
Nutrient Requirements ◽  
Trophic Shift ◽  
Gut Fullness ◽  
Trophic Shifts ◽  
Zostera Capricorni

To elucidate the trophic status of hemiramphids, the diets of three species from subtropical south-east Queensland were investigated. All undergo a marked ontogenetic trophic shift from an animal to plant diet, which occurred between 50 and 70 mm standard length (Ls) for Arrhamphus sclerolepis krefftii (freshwater) and between 80 and 110 mm Ls for both Hyporhamphus regularis ardelio and H. quoyi (both marine). After the ontogenetic shift, the diet of A. sclerolepis krefftii is dominated by filamentous algae, whereas the diet of the two marine species is dominated by Zostera capricorni. The two marine species feed mainly during the day, with gut fullness dropping markedly after dusk. Neither showed evidence of a diel trophic shift between herbivory and carnivory that has been reported for other hemiramphids. The lack of diel trophic switching in these subtropical hemiramphids may suggest that latitudinal effects on daylength and/or water temperature may influence the extent to which hemiramphids switch periodically to animal prey from an otherwise essentially herbivorous diet in order to balance their nutrient requirements.

6. Reef fish and other major predators

2021 ◽  
pp. 68-84
Author(s):  
Charles Sheppard
Keyword(s):  
Plant Material ◽  
Nitrogen Isotope ◽  
Algal Turf ◽  
Bare Rock ◽  
Geographical Patterns ◽  
Turf Algae ◽  
Reef Degradation ◽  
Almost All ◽  
Total Species ◽  
Plankton Feeders

Fish, like corals, have geographical patterns across regions and across individual reefs, being structured in the latter case by wave energy and depth. The thousands of species show a variety of feeding patterns. Detritus feeders are very abundant, feeding on the detritus on the seabed, especially in the fine, filamentous algal turf on apparently bare rock. Plankton feeders are common also, and herbivorous fishes show a large abundance, perhaps a quarter of the total species present, cropping algae that otherwise would grow unchecked and smother coral. Since turf algae also contain many micro-species and detritus, most herbivores also ingest much food other than simple plant material. Carnivores range from extreme specialists, such as polyp-picking butterflyfish, to generalists. Sharks and barracuda only consume other fish and generally are at the top of their food chains. The complicated ecological structure of the food webs can be clarified by analysing nitrogen isotope ratios in their tissues. Other important coral carnivores include the crown of thorns starfish, which can remove almost all living coral on a reef when it develops into plagues. Overfishing by humans greatly disturbs the equilibrium of a reef, and this is increasingly causing reef degradation.

scholarly journals Variabilitas Genetik dan Fenotipik Karakter Pertumbuhan dan Komponen Pertumbuhan Benih Hasil Perbanyakan Vegetatif Klon-klon Teh yang Diperoleh melalui Persilangan Buatan

Jurnal Agro ◽  
10.15575/158 ◽  
2015 ◽  
Vol 2 (1) ◽  
pp. 10-14
Author(s):  
Heri Syahrian Khomaeni ◽  
Vitria Puspitasari Rahadi ◽  
Endi Ruhaendi ◽  
Budi Santoso
Keyword(s):  
Vegetative Propagation ◽  
Plant Material ◽  
Phenotypic Variability ◽  
Block Design ◽  
Dry Weight ◽  
Tea Plant ◽  
Root Dry Weight ◽  
Randomized Block Design ◽  
Almost All ◽  
Growth Ability

Perbanyakan tanaman teh dengan menggunakan setek satu daun saat ini merupakan cara yang umum untuk memenuhi kebutuhan bahan tanaman dalam jumlah yang banyak dengan waktu yang singkat. Salah satu syarat dalam perakitan klon teh unggul baru adalah kemudahan klon tersebut untuk diperbanyak secara vegetatif. Hal ini dikarenakan klon yang mudah diperbanyak secara vegetatif lebih disukai oleh para pekebun. Salah satu pengujian yang harus dilakukan dalam proses pemuliaan tanaman teh adalah uji perbanyakan vegetatif pada kandidat klon unggul baru. Penelitian ini bertujuan untuk mengetahui variabilitas kemampuan pertumbuhan dan beberapa komponen pertumbuhan benih setek dalam uji perbanyakan vegetatif. Penelitian dilaksanakan di Persemaian Pemuliaan Kebun Percobaan Pusat Penelitian Teh dan Kina Gambung. Percobaan menggunakan Rancangan Acak Kelompok (RAK) dengan 19 klon sebagai perlakuan yang diulang tiga kali, setiap perlakuan ditanam 52 benih setek. Hasil penelitian menunjukkan bahwa hampir seluruh variabilitas genetik pada karakter yang diamati tergolong dalam kategori luas, kecuali untuk karakter panjang akar, dan berat kering akar. Variabilitas fenotipik menunjukkan bahwa hampir seluruh karakter yang diamati tergolong dalam kategori luas, kecuali berat kering akar. Currently, propagation of tea plant using one leaf is a common way to fulfil the need of plant material in large quantity also short in time. One of requirements in assembling new superior tea clone is the easy of clone to be propagated vegetatively. Clone which is easy to propagate in vegetative way is apt more by the gardeners. One required test on tea plant breeding process is vegetative propagation test of new superior clone candidates. This research aimed to determine variability of growth ability and several growth components of cutting seed in vegetative propagation. The research was carried out in Breeding Nursery, Experimental Field of Tea and Cinchona Research Institute Gambung. The trial was set in Randomized Block Design (RBD) with 19 clones as the treatment which was repeated three times, each treatment consisted of 52 cutting seeds. The result showed that almost all genetic variability of characters observed were included to wide category, except for root length and root dry weight characters. Phenotypic variability showed that nearly all characters observed were comprised to wide category, except root dry weight.

scholarly journals Mechanical modelling of tooth wear

2016 ◽  
Vol 13 (120) ◽  
pp. 20160399 ◽  
Author(s):  
Aleksis Karme ◽  
Janina Rannikko ◽  
Aki Kallonen ◽  
Marcus Clauss ◽  
Mikael Fortelius
Keyword(s):  
Plant Material ◽  
Tooth Wear ◽  
Tissue Loss ◽  
Dental Tissue ◽  
Direct Transformation ◽  
Computed Tomography Scanning ◽  
Height Change ◽  
The Mean ◽  
Tomography Scanning

Different diets wear teeth in different ways and generate distinguishable wear and microwear patterns that have long been the basis of palaeodiet reconstructions. Little experimental research has been performed to study them together. Here, we show that an artificial mechanical masticator, a chewing machine, occluding real horse teeth in continuous simulated chewing (of 100 000 chewing cycles) is capable of replicating microscopic wear features and gross wear on teeth that resemble wear in specimens collected from nature. Simulating pure attrition (chewing without food) and four plant material diets of different abrasives content (at n = 5 tooth pairs per group), we detected differences in microscopic wear features by stereomicroscopy of the chewing surface in the number and quality of pits and scratches that were not always as expected. Using computed tomography scanning in one tooth per diet, absolute wear was quantified as the mean height change after the simulated chewing. Absolute wear increased with diet abrasiveness, originating from phytoliths and grit. In combination, our findings highlight that differences in actual dental tissue loss can occur at similar microwear patterns, cautioning against a direct transformation of microwear results into predictions about diet or tooth wear rate.

Habitat Association of Klebsiella Species

1985 ◽  
Vol 6 (2) ◽  
pp. 52-58 ◽  
Author(s):  
Susan T. Bagley
Keyword(s):  
Drinking Water ◽  
Gastrointestinal Tract ◽  
Surface Waters ◽  
Industrial Effluents ◽  
Opportunistic Pathogen ◽  
Habitat Associations ◽  
Habitat Association ◽  
Klebsiella Species ◽  
Almost All ◽  
Polluted Waters

AbstractThe genus Klebsiella is seemingly ubiquitous in terms of its habitat associations. Klebsiella is a common opportunistic pathogen for humans and other animals, as well as being resident or transient flora (particularly in the gastrointestinal tract). Other habitats include sewage, drinking water, soils, surface waters, industrial effluents, and vegetation. Until recently, almost all these Klebsiella have been identified as one species, ie, K. pneumoniae. However, phenotypic and genotypic studies have shown that “K. pneumoniae” actually consists of at least four species, all with distinct characteristics and habitats. General habitat associations of Klebsiella species are as follows: K. pneumoniae—humans, animals, sewage, and polluted waters and soils; K. oxytoca—frequent association with most habitats; K. terrigena— unpolluted surface waters and soils, drinking water, and vegetation; K. planticola—sewage, polluted surface waters, soils, and vegetation; and K. ozaenae/K. rhinoscleromatis—infrequently detected (primarily with humans).

SEM Cold Stage Techniques for the Observation of Vegetative and Floral Apices of Oat (Avena sativa L.) Plants

1977 ◽  
Vol 35 ◽  
pp. 590-591
Author(s):  
B. K. Kirchoff ◽  
L.F. Allard ◽  
W.C. Bigelow
Keyword(s):  
Critical Point ◽  
Avena Sativa ◽  
Substantial Improvement ◽  
Fresh Tissue ◽  
Cold Stage ◽  
Critical Point Drying ◽  
Almost All ◽  
Cell Collapse ◽  
Conductive Paint ◽  
Carbon Based

In attempting to use the SEM to investigate the transition from the vegetative to the floral state in oat (Avena sativa L.) it was discovered that the procedures of fixation and critical point drying (CPD), and fresh tissue examination of the specimens gave unsatisfactory results. In most cases, by using these techniques, cells of the tissue were collapsed or otherwise visibly distorted. Figure 1 shows the results of fixation with 4.5% formaldehyde-gluteraldehyde followed by CPD. Almost all cellular detail has been obscured by the resulting shrinkage distortions. The larger cracks seen on the left of the picture may be due to dissection damage, rather than CPD. The results of observation of fresh tissue are seen in Fig. 2. Although there is a substantial improvement over CPD, some cell collapse still occurs.Due to these difficulties, it was decided to experiment with cold stage techniques. The specimens to be observed were dissected out and attached to the sample stub using a carbon based conductive paint in acetone.

Electron microscopy studies of plasma-sprayed materials

1983 ◽  
Vol 41 ◽  
pp. 70-71
Author(s):  
K.R. Subramanian ◽  
A.H. King ◽  
H. Herman
Keyword(s):  
Plasma Spraying ◽  
Substrate Surface ◽  
Flame Temperature ◽  
Ceramic Coatings ◽  
Metallic Substrates ◽  
Hot Plasma ◽  
Almost All ◽  
Plasma Sprayed ◽  
Hostile Environments ◽  
Plasma Spraying Process

Plasma spraying is a technique which is used to apply coatings to metallic substrates for a variety of purposes, including hardfacing, corrosion resistance and thermal barrier applications. Almost all of the applications of this somewhat esoteric fabrication technique involve materials in hostile environments and the integrity of the coatings is of paramount importance: the effects of process variables on such properties as adhesive strength, cohesive strength and hardness of the substrate/coating system, however, are poorly understood.Briefly, the plasma spraying process involves forming a hot plasma jet with a maximum flame temperature of approximately 20,000K and a gas velocity of about 40m/s. Into this jet the coating material is injected, in powder form, so it is heated and projected at the substrate surface. Relatively thick metallic or ceramic coatings may be speedily built up using this technique.

Vacuum System to Minimize the Specimen Contamination of High-Performance EM

1977 ◽  
Vol 35 ◽  
pp. 68-69
Author(s):  
N. Yoshimura ◽  
K. Shirota ◽  
T. Etoh
Keyword(s):  
Electron Microscope ◽  
High Speed ◽  
High Performance ◽  
High Vacuum ◽  
Vacuum System ◽  
Pump System ◽  
Pumping System ◽  
Diffusion Pump ◽  
Almost All ◽  
Cascade Type

One of the most important requirements for a high-performance EM, especially an analytical EM using a fine beam probe, is to prevent specimen contamination by providing a clean high vacuum in the vicinity of the specimen. However, in almost all commercial EMs, the pressure in the vicinity of the specimen under observation is usually more than ten times higher than the pressure measured at the punping line. The EM column inevitably requires the use of greased Viton O-rings for fine movement, and specimens and films need to be exchanged frequently and several attachments may also be exchanged. For these reasons, a high speed pumping system, as well as a clean vacuum system, is now required. A newly developed electron microscope, the JEM-100CX features clean high vacuum in the vicinity of the specimen, realized by the use of a CASCADE type diffusion pump system which has been essentially improved over its predeces- sorD employed on the JEM-100C.

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