Red crabs in rain forest, Christmas Island: removal and relocation of leaf-fall

ABSTRACTField experiments comparing leaf-fall in the presence and absence of the red land crab, Gecarcoidea natalis, in rain forest on Christmas Island, Indian Ocean showed that, by eating and returning leaves to their burrows, they significantly reduced accumulation of leaf-fall on the forest floor. Red crabs removed 30–50% of the leaf-fall at the experimental sites during the study. Differences in leaf-fall mass between crab-access and exclusion quadrats were positively correlated with the density of foraging red crabs. Red crabs also generated spatial heterogeneity in the distribution of litter on the forest floor by returning litter to their burrows. Leaves lined chambers of 64% of excavated burrows and litter biomass around the entrances was significantly greater than that on off-burrow locations. This was reflected in the significantly higher concentrations of organic matter and nutrients (N, P, K, Ca, Na, and Mg) associated with soils near burrow entrances. These results suggest that a single species, G. natalis, is the major processor of leaf-fall in rain forest on Christmas Island and may affect (1) the temporal and spatial patterns of nutrient availability and (2) the diversity and biomass of the litter fauna.

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Burrow Dynamics of the Red Land Crab Gecarcoidea Natalis (Brachyura, Gecarcinidae) in Rain Forest on Christmas Island (Indian Ocean)

Journal of Crustacean Biology ◽

10.1651/c-2447 ◽

2004 ◽

Vol 24 (2) ◽

pp. 340-349 ◽

Cited By ~ 11

Author(s):

Peter T. Green

Keyword(s):

Indian Ocean ◽

Rain Forest ◽

Land Crab ◽

Christmas Island ◽

Gecarcoidea Natalis

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Field Observations of Moulting and Moult Increment in the Red Land Crab, Gecarcoidea Natalis (Brachyura, Gecarcinidae), on Christmas Island (Indian Ocean)

Crustaceana ◽

10.1163/156854004323037937 ◽

2004 ◽

Vol 77 (1) ◽

pp. 125-128 ◽

Cited By ~ 9

Author(s):

Peter Green

Keyword(s):

Indian Ocean ◽

Field Observations ◽

Land Crab ◽

Christmas Island ◽

Gecarcoidea Natalis

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Red crabs in rain forest, Christmas Island: removal and fate of fruits and seeds

Journal of Tropical Ecology ◽

10.1017/s0266467400005162 ◽

1991 ◽

Vol 7 (1) ◽

pp. 113-122 ◽

Cited By ~ 30

Author(s):

Dennis J. O'Dowd ◽

P. S. Lake

Keyword(s):

Seed Predation ◽

Rain Forest ◽

Nitrogen Concentration ◽

Oceanic Islands ◽

Fruit Removal ◽

Land Crab ◽

Christmas Island ◽

Direct Observations ◽

Land Crabs ◽

Seed Coats

ABSTRACTThe red land crab (Gecarcoidea nalalis) is the major collector of fruits and seeds from the rain forest Moor on Christmas Island, Indian Ocean. At three sites, they rapidly removed fruits and seeds of 17 species tested (usually within 12 h after placement) and most were taken to crab burrows. Direct observations of seed predation, and application of estimated chelar forces of red crabs indicated that seeds of many species, especially those with thin seed coats, are likely to be killed through handling. However, removal of some resistant seeds to burrows may be favourable for seedling establishment when canopy gaps occur. Fruit removal rates by crabs were positively related to nitrogen concentration in fruit tissues but negatively correlated with condensed tannins. These observations suggest that seed predation by land crabs may affect the success of colonization and the relative abundance of plants on oceanic islands.

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Ultrastructural analysis of unique glycoconjugates in the rat olfactory system

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100124859 ◽

1992 ◽

Vol 50 (1) ◽

pp. 890-891

Author(s):

James E. Crandall ◽

Linda C. Hassinger ◽

Gerald A. Schwarting

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Monoclonal Antibodies ◽

Olfactory System ◽

Olfactory Bulbs ◽

Temporal And Spatial Patterns ◽

Carbohydrate Epitopes ◽

Olfactory Systems ◽

Temporal And Spatial ◽

Cell Surface Glycoconjugates

Cell surface glycoconjugates are considered to play important roles in cell-cell interactions in the developing central nervous system. We have previously described a group of monoclonal antibodies that recognize defined carbohydrate epitopes and reveal unique temporal and spatial patterns of immunoreactivity in the developing main and accessory olfactory systems in rats. Antibody CC2 reacts with complex α-galactosyl and α-fucosyl glycoproteins and glycolipids. Antibody CC1 reacts with terminal N-acetyl galactosamine residues of globoside-like glycolipids. Antibody 1B2 reacts with β-galactosyl glycolipids and glycoproteins. Our light microscopic data suggest that these antigens may be located on the surfaces of axons of the vomeronasal and olfactory nerves as well as on some of their target neurons in the main and accessory olfactory bulbs.

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Hawk kite as potential bird scare device (the case of pigeons and grain processing factory)

Ukrainian Journal of Ecology ◽

10.15421/2018_350 ◽

2018 ◽

Vol 8 (2) ◽

pp. 334-336

Author(s):

A. V. Matsyura

Keyword(s):

Spatial Patterns ◽

Repellent Effect ◽

Preliminary Results ◽

Temporal And Spatial Patterns ◽

Grain Processing ◽

Feral Pigeons ◽

Temporal And Spatial ◽

Bird Behavior ◽

Hooded Crows

Here we presented the preliminary results of hawk kite usage against the feral pigeons in some grain processing factory. We studied the temporal and spatial patterns of repellent effect and bird behavior. We suggested the feral pigeons gradually increase the level of tolerance towards the hawk kite if no additional repellent measures were undertaken. Moreover, even initially the feral pigeons demonstrate higher tolerance towards the hawk kite compared to the Rooks or Hooded Crows.

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Evolution of Mouse T-box Genes by Tandem Duplication and Cluster Dispersion

Genetics ◽

10.1093/genetics/144.1.249 ◽

1996 ◽

Vol 144 (1) ◽

pp. 249-254 ◽

Cited By ~ 4

Author(s):

Sergei I Agulnik ◽

Nancy Garvey ◽

Sarah Hancock ◽

Ilya Ruvinsky ◽

Deborah L Chapman ◽

...

Keyword(s):

Tandem Duplication ◽

Crossing Over ◽

Dna Binding Domain ◽

Gene Products ◽

New Members ◽

Ancestral Gene ◽

T Box ◽

Temporal And Spatial Patterns ◽

Temporal And Spatial ◽

T Locus

Abstract The T-box genes comprise an ancient family of putative transcription factors conserved across species as divergent as Mus musculus and Caenorhabditis elegans. All T-box gene products are characterized by a novel 174-186amino acid DNA binding domain called the T-box that was first discovered in the polypeptide products of the mouse T locus and the Drosophila melanogaster optomotor-blind gene. Earlier studies allowed the identification of five mouse T-box genes, T, Tbx1-3, and Tbr1, that all map to different chromosomal locations and are expressed in unique temporal and spatial patterns during embryogenesis. Here, we report the discovery of three new members of the mouse T-box gene family, named Tbx4, Tbx5, and Tbx6. Two of these newly discovered genes, Tbx4 and Tbx5, were found to be tightly linked to previously identified T-box genes. Combined results from phylogenetic, linkage, and physical mapping studies provide a picture for the evolution of a T-box subfamily by unequal crossing over to form a two-gene cluster that was duplicated and dispersed to two chromosomal locations. This analysis suggests that Tbx4 and Tbx5 are cognate genes that diverged apart from a common ancestral gene during early vertebrate evolution.

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