New Information on Scavenging and Selective Feeding Behaviour of Tyrannosaurids

A large number of hypotheses have been proposed to explain the adaptive significance and evolution of the endophagous-feeding mode, nutritional benefits being considered to be one of the main advantages. Leaf-mining insects should feed on most nutritional tissues and avoid tissues with high structural and/or biochemical plant defences. This selective feeding behaviour could furthermore be reinforced by manipulating the plant physiology, as suggested by the autumnal formation of ‘green islands’ around mining caterpillars in yellow leaves. The question we address here is how such metabolic manipulation occurs and what the nutritional consequences for the insect are. We report a large accumulation of cytokinins in the mined tissues which is responsible for the preservation of functional nutrient-rich green tissues at a time when leaves are otherwise turning yellow. The analogy with other plant manipulating organisms, in particular galling insects, is striking.

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Selective Feeding and Microalgal Consumption Rates by Crown-of-Thorns Seastar (Acanthaster cf. solaris) Larvae

10.20944/preprints201611.0124.v1 ◽

2016 ◽

Author(s):

Camille Mellin ◽

Claire Lugrin ◽

Ken Okaji ◽

David S. Francis ◽

Sven Uthicke

Keyword(s):

Feeding Behaviour ◽

Energy Content ◽

Algal Species ◽

Larval Survival ◽

Larval Feeding ◽

Selective Feeding ◽

Feeding Experiments ◽

Cell Counts ◽

Phytoplankton Communities ◽

Spatio Temporal

Outbreaks of the crown-of-thorns seastar (CoTS) represent a major cause of coral loss on the Great Barrier Reef. Outbreaks might be explained by enhanced larval survival supported by higher phytoplankton availability after flood events, yet little is known about CoTS larvae feeding behaviour, in particular their potential for selective feeding. Here, single- and mixed-species feeding experiments were conducted on CoTS bipinnaria larvae using five algae (Phaeodactylum tricornutum, Pavlova lutheri, Tisochrysis lutea , Dunaliella sp. and Chaetoceros sp.) and two algal concentrations (1000 and 2500 algae mL-1). Cell counts using flow-cytometry at the beginning and end of each incubation experiment allowed us to calculate the filtration and ingestion rates of each species by CoTS larvae. In line with previous studies, CoTS larvae ingested more algae when initial algal concentration was higher. We found evidence for the selective ingestion of some species (Chaetoceros sp., Dunaliella sp.) over others (P. lutheri, P. tricornutum). The preferred algal species had the highest energy content, suggesting that CoTS selectively ingested the most energetic algae. Ultimately, combining these results with spatio-temporal patterns in phytoplankton communities will help elucidate the role of larval feeding behaviour in determining the frequency and magnitude of CoTS outbreaks.

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Influence of a selective feeding behaviour by the blue mussel Mytilus trossulus on the assimilation of 109Cd from environmentally relevant seston matrices

Marine Ecology Progress Series ◽

10.3354/meps192181 ◽

2000 ◽

Vol 192 ◽

pp. 181-193 ◽

Cited By ~ 11

Author(s):

Z Arifin ◽

LI Bendell-Young

Keyword(s):

Feeding Behaviour ◽

Blue Mussel ◽

Mytilus Trossulus ◽

Selective Feeding ◽

Mussel Mytilus Trossulus

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Selective feeding behaviour of key free-living protists: avenues for continued study

Aquatic Microbial Ecology ◽

10.3354/ame01229 ◽

2008 ◽

Vol 53 ◽

pp. 83-98 ◽

Cited By ~ 101

Author(s):

DJS Montagnes ◽

AB Barbosa ◽

J Boenigk ◽

K Davidson ◽

K Jürgens ◽

...

Keyword(s):

Feeding Behaviour ◽

Selective Feeding ◽

Free Living

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Lattice Imaging of Twin, Lath and α/Martensite Boundaries in Duplex Low Carbon Steels

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100078195 ◽

1977 ◽

Vol 35 ◽

pp. 118-119

Author(s):

J. Y. Koo ◽

G. Thomas

Keyword(s):

High Resolution Electron Microscopy ◽

Ferrite Matrix ◽

Carbon Steels ◽

Bright Field Image ◽

Low Carbon ◽

Lattice Imaging ◽

Bright Field ◽

Lattice Image ◽

New Information ◽

Resolution Electron

High resolution electron microscopy has been shown to give new information on defects(1) and phase transformations in solids (2,3). In a continuing program of lattice fringe imaging of alloys, we have applied this technique to the martensitic transformation in steels in order to characterize the atomic environments near twin, lath and αmartensite boundaries. This paper describes current progress in this program.Figures A and B show lattice image and conventional bright field image of the same area of a duplex Fe/2Si/0.1C steel described elsewhere(4). The microstructure consists of internally twinned martensite (M) embedded in a ferrite matrix (F). Use of the 2-beam tilted illumination technique incorporating a twin reflection produced {110} fringes across the microtwins.

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Stereo Electron Microscopy Applied to High Resolution Freeze-Etch Replicas

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100068527 ◽

1970 ◽

Vol 28 ◽

pp. 306-307

Author(s):

L. Andrew Staehelin

Keyword(s):

Electron Microscopy ◽

Plastic Deformation ◽

High Resolution ◽

Smooth Surfaces ◽

Small Particles ◽

Membrane Surfaces ◽

Wide Acceptance ◽

New Information ◽

Number Of Particles ◽

Small Holes

Freeze-etched membranes usually appear as relatively smooth surfaces covered with numerous small particles and a few small holes (Fig. 1). In 1966 Branton (1“) suggested that these surfaces represent split inner mem¬brane faces and not true external membrane surfaces. His theory has now gained wide acceptance partly due to new information obtained from double replicas of freeze-cleaved specimens (2,3) and from freeze-etch experi¬ments with surface labeled membranes (4). While theses studies have fur¬ther substantiated the basic idea of membrane splitting and have shown clearly which membrane faces are complementary to each other, they have left the question open, why the replicated membrane faces usually exhibit con¬siderably fewer holes than particles. According to Branton's theory the number of holes should on the average equal the number of particles. The absence of these holes can be explained in either of two ways: a) it is possible that no holes are formed during the cleaving process e.g. due to plastic deformation (5); b) holes may arise during the cleaving process but remain undetected because of inadequate replication and microscope techniques.

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Trial production of γ-type energy filtering TEM

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100139391 ◽

1995 ◽

Vol 53 ◽

pp. 604-605

Author(s):

Y. Taniguchi ◽

E. Nakazawa ◽

S. Taya

Keyword(s):

Magnetic Energy ◽

Electron Optics ◽

Electron Microscopic ◽

Mass Spectrometers ◽

Ion Optics ◽

Energy Filtering ◽

New Information ◽

New Type ◽

Fringing Fields

Imaging energy filters can add new information to electron microscopic images with respect to energy-axis, so-called electron spectroscopic imaging (ESI). Recently, many good results have been reported using this imaging technique. ESI also allows high-contrast observation of unstained biological samples, becoming a trend of the field of morphology. We manufactured a new type of energy filter as a trial production. This energy filter consists of two magnets, and we call γ-filter since the trajectory of electrons shows ‘γ’-shape inside the filter. We evaluated the new energyγ-filter TEM with the γ-filter.Figure 1 shows schematic view of the electron optics of the γ-type energy filter. For the determination of the electron-optics of the γ-type energy filter, we used the TRIO (Third Order Ion Optics) program which has been developed for the design of high resolution mass spectrometers. The TRIO takes the extended fringing fields (EFF) into consideration. EFF makes it difficult to design magnetic energy filters with magnetic sector fields.

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