Sexual Dimorphism and Niche Divergence: Feeding Habits of the Arafura Filesnake

10.2307/5393 ◽  
1993 ◽  
Vol 62 (4) ◽  
pp. 737 ◽  
Author(s):  
Darryl Houston ◽  
Richard Shine
Keyword(s):  
Sexual Dimorphism ◽  
Feeding Habits ◽  
Niche Divergence

scholarly journals Antennal and palpal sensilla of three predatory Lispe species (Diptera: Muscidae): an ultrastructural investigation

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Genting Liu ◽  
Qike Wang ◽  
Xianhui Liu ◽  
Xinyu Li ◽  
Xiunan Pang ◽  
...  
Keyword(s):  
Electron Microscopy ◽  
Scanning Electron Microscopy ◽  
Sexual Dimorphism ◽  
Feeding Habits ◽  
Visual Signal ◽  
Chemical Signal ◽  
Basiconic Sensilla ◽  
Unique Character ◽  
Maxillary Palps ◽  
Scanning Electron

AbstractAntennae and maxillary palps are the most important chemical reception organs of flies. So far, the morphology of antennae and maxillary palps of flies of most feeding habits have been well described, except for that of relatively rare aquatic predatory species. This study describes sensilla on antennae and maxillary palps of three aquatic predatory Lispe species: Lispe longicollis, L. orientalis and L. pygmaea. Types, distribution, and density of sensilla are characterised via light and scanning electron microscopy. One type of mechanoreceptors is found on antennal scape. Mechanoreceptors (two subtypes) and one single pedicellar button (in L. pygmaea) are located on antennal pedicel. Four types of sensilla are discovered on antennal postpedicel: trichoid sensilla, basiconic sensilla (three subtypes), coeloconic sensilla and clavate sensilla. A unique character of these Lispe species is that the coeloconic sensilla are distributed sparsely on antennal postpedicel. Mechanoreceptors and basiconic sensilla are observed on the surface of maxillary palps in all three species. We demonstrated clear sexual dimorphism of the maxillary palps in some of the Lispe species, unlike most other Muscidae species, are larger in males than females. This, along with their courtship dance behaviour, suggest their function as both chemical signal receiver and visual signal conveyer, which is among the few records of a chemical reception organ act as a signal conveyer in insects.

scholarly journals Feeding habits, sexual dimorphism and size at maturity of the lizard Cnemidophorus ocellifer (Spix, 1825) (Teiidae) in a reforested restinga habitat in northeastern Brazil

2010 ◽  
Vol 70 (2) ◽  
pp. 409-416 ◽  
Author(s):  
GG. Santana ◽  
A. Vasconcellos ◽  
YEA. Gadelha ◽  
WLS. Vieira ◽  
WO. Almeida ◽  
...  
Keyword(s):  
Sexual Dimorphism ◽  
Sexual Maturity ◽  
Feeding Habits ◽  
Structural Complexity ◽  
Northeastern Brazil ◽  
Size At Maturity ◽  
Insect Larvae ◽  
The Poor ◽  
Significant Difference ◽  
Poor Soil

The feeding habits, the sexual dimorphism in size and sexual maturity of the actively foraging lizard Cnemidophorusocellifer were analysed in an area of a reforested Restinga habitat located in the municipality of Mataraca, along the northern-most coast of Paraíba State, Brazil. Seventy-five specimens of C. ocellifer were examined (46 males and 29Â females). Of this total, only 23 specimens had prey in their stomachs. The most frequent prey consumed items were orthopterans (50%), coleopterans (23.9%) and arachnids (10.9%); termites and insect larvae were less consumed (both with 2.2%). There were no significant differences observed between the numbers of prey consumed by either males or females. There were significant differences in SVL (snout-vent length) between the sexes, with males attaining larger SVL values. When the influence of SVL was removed from the analyses, sexual dimorphism in the form was still reflected in the head size of these lizards. Sexual maturity in females and males was attained with SVL of 42.2 and 49.0 mm respectively. Although no significant difference was observed between the SVL of the females and the number of eggs produced, there was a clear tendency for larger females to produce more eggs. The low structural complexity of the vegetation and the poor soil quality in the reforested restinga area examined does not furnish favourable habitat for insect and termite larvae, contributing to the marked differences in the diet of the population of C. ocellifer observed in the present study in relation to the diet of their conspecifics in undisturbed areas of restinga, cerrado and caatinga.

scholarly journals PRESENCIA DE UROTRYGON MICROPHTHALMUM (ELASMOBRANCHII: UROLOPHIDAE) EN AGUAS BAJAS DE MARANHÃO (BRASIL) Y NOTAS SOBRE SU BIOLOGIA

2016 ◽  
Vol 29 ◽  
Author(s):  
Zafira S. Almeida ◽  
Jorge S. Nunes ◽  
Clarissa L. Costa
Keyword(s):  
Sexual Dimorphism ◽  
Feeding Habits ◽  
Stomach Contents ◽  
Total Length ◽  
Sexual Stages

From October 1997 to April, 1998 seventy-nine specimens of the ray Urotrygon microphthalmumwere captured, all of them showing sexual dimorphism. They were processed in order to study their morphometrics, feeding habits, and reproduction. The largest was 300 mm in total length and the smallest one 64.4 mm, weighing 103.4 g and 12.5 g respectively. They fed mainly on crustaceans and ploychaeta; of the stomach contents 94.5 % were shrimp and 5.49% polychaeta. 7.6% of the total had empty stomachs. As far as reproduction, three sexual stages were found:  51% juvenile, 30% adult and 19% pregnant, with an average of three embryos per uterus. Among the male fishes analysed 84.4% were juvenile and 16.6% adults

The Feeding Habits of the Shovel-Tusked Gomphotheres: Evidence From Tusk Wear Patterns

Paleobiology ◽  
1992 ◽  
Vol 18 (2) ◽  
pp. 132-147 ◽  
Author(s):  
W. David Lambert
Keyword(s):  
Sexual Dimorphism ◽  
Feeding Behavior ◽  
Direct Evidence ◽  
Feeding Habits ◽  
Theoretical Models ◽  
African Elephants ◽  
Water Plants

The shovel-tusked gomphotheres are normally portrayed scooping up water plants with their shovellike mandibular tusks. This portrayal is based on speculation about the possible functions of the lower tusks and misinterpretation of mandibular-tusk wear patterns that goes back to the 1920s and 1930s. In addition, most literature concerning shovel-tusker feeding behavior ignores the possibility that the upper tusks may have had a role in feeding, as they do in modern African elephants. Because wear patterns on tusks provide direct evidence as to how tusks were used during feeding, I examined and interpreted patterns on the lower and upper tusks of shovel-tusked gomphotheres on the basis of theoretical models of tusk wear to determine how the tusks were used in feeding.This examination led to the following conclusions. (1) The genus Amebelodon was characterized by feeding opportunism, gathering food with both its lower and upper tusks in a variety of ways. (2) There is evidence for similar flexibility within the genus Serbelodon. (3) Wear patterns on mandibular tusks of Platybelodon grangeri and Torynobelodon barnumbrowni indicate that these taxa did not practice mandibular shoveling but used these tusks to cut tough vegetation in a specialized fashion. (4) The flaplike trunks (probosces) generally attributed to shovel-tusked gomphotheres in restorations are shown almost certainly to be erroneous; morphological and functional evidence suggests that these animals had trunks similar to those of modern elephants. (5) Strong tusk sexual dimorphism is unknown in the shovel-tusked gomphotheres except for Platybelodon and should not be found in any taxa that relied on their tusks for procuring food. New restorations of both Amebelodon and Platybelodon are provided that are more consistent with the actual evidence bearing on their feeding behavior.

scholarly journals Omalus sculpticollis as the Main Enemy of Psenulus fuscipennis (Hymenoptera, Chrysididae, Crabronidae) in the Crimea, Ukraine

2014 ◽  
Vol 48 (1) ◽  
pp. 11-26 ◽  
Author(s):  
K. V. Martynova ◽  
A. V. Fateryga
Keyword(s):  
Sexual Dimorphism ◽  
Nature Reserve ◽  
Feeding Habits ◽  
Instar Larva ◽  
Structural Features ◽  
The Crimea ◽  
Taxonomical Position ◽  
First Time ◽  
Parasite Complex ◽  
Trap Nest

Abstract he trap-nest technique was tested in the Karadag Nature Reserve (Crimea, Ukraine). In the result the enemies of Psenulus fuscipennis (Dahlbom, 1843), which caused damage to its progeny, were revealed: Omalus sculpticollis Abeille, 1878, Melittobia acasta Walker, 1839, Perithous septemcinctorius (Th unberg, 1822), and Trichodes apiarius Linnaeus, 1758. Th e structure of the parasite complex, voltinity of the species, comparative eff ectiveness of enemies are determined on the basis of observed data. Th e taxonomical position of O. sculpticollis is discussed, its sexual dimorphism is illustrated, the detailed description of the cocoon and some structural features of the last instar larva are given for the first time. Feeding habits of the larvae of O. sculpticollis are examined and the delicate aspects of interaction with the host are discussed. Short notes on terminology are given

Sexual dimorphism in trophic morphology and feeding behavior of wolf spiders (Araneae: Lycosidae) as a result of differences in reproductive roles

2002 ◽  
Vol 80 (4) ◽  
pp. 679-688 ◽  
Author(s):  
Sean E Walker ◽  
Ann L Rypstra
Keyword(s):  
Sexual Dimorphism ◽  
Feeding Behavior ◽  
Wolf Spider ◽  
Foraging Success ◽  
Wolf Spiders ◽  
Niche Divergence ◽  
Trophic Morphology ◽  
Males And Females ◽  
Almost All ◽  
The Relationship

Sexual dimorphism in animals is thought to be a result of differences between the sexes in the relationship between reproductive success and a trait, or a result of intersexual niche divergence. Intersexual niche divergence occurs as a result of competition between the sexes and is generally inferred from sexual dimorphism in morphological features associated with feeding. However, differences between the sexes in trophic morphology can be a result of either intersexual niche divergence or differences in the relationship between foraging success and reproduction between the sexes. In this study we examined sex differences in the trophic morphology of six wolf spider species and in the feeding behavior of two of these species. Females were larger than males in almost all characteristics even after differences in body size were accounted for, and killed and consumed more prey. We found little evidence of intersexual niche divergence based on differences in the relative prey sizes preferred by males and females of two species. Our data suggest that differences in the reproductive roles of males and females have resulted in foraging success being more important for female fitness than for male fitness and that differences in reproductive roles can result in sexual dimorphism.

scholarly journals Sexual dimorphism and skull size and shape in the highly specialized snake species, Aipysurus eydouxii (Elapidae: Hydrophiinae)

PeerJ ◽  
2021 ◽  
Vol 9 ◽  
pp. e11311
Author(s):  
Bartosz Borczyk ◽  
Łukasz Paśko ◽  
Jan Kusznierz ◽  
Stanisław Bury
Keyword(s):  
Sexual Dimorphism ◽  
Body Length ◽  
Prey Size ◽  
Feeding Habits ◽  
Skull Morphology ◽  
Data Set ◽  
Skull Shape ◽  
Size And Shape ◽  
Mandibular Fossa ◽  
Males And Females

Background Snakes exhibit sexual dimorphism in both head size and shape. Such differences are often attributed to different reproductive roles and feeding habits. We aim to investigate how sexual dimorphism is displayed in the highly specialised fish-egg-eating snake, Aipysurus eydouxii, by analysing two complementary features: body size and skull morphology. Methods We used data on body length, weight, and skull shape from 27 measurements of 116 males and females of A. eydouxii. We investigated both sexual dimorphism and allometric (multivariate and bi-variate) properties of skull growth in the analysed data set. Results We found that although there was female-biased sexual size dimorphism in body length, females were not heavier than males, contrary to what is commonly observed pattern among snakes. Moreover, females tend to possess relatively smaller heads than males. However, we only found very subtle differences in skull shape reflected in nasal width, mandibular fossa, quadrate crest and quadrate length. Discussion We suggest that the feeding specialisation in A. eydouxii does not allow for an increase in body thickness and the size of the head above a certain threshold. Our results may be interpreted as support for prey-size divergence as a factor driving skull dimorphism since such species in which the sexes do not differ in prey size also shows very subtle or no differences in skull morphology.

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