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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
81

Semiochemicals and social signalling in the wild European rabbit (Oryctolagus cuniculus(L.)

Hayes, Richard Andrew, University of Western Sydney, Hawkesbury, Faculty of Science and Technology, School of Science January 2000 (has links)
The European rabbit lives in defined social groups of between two and about twenty individuals. There are distinct social hierarchies within each group. Rabbits are known to scent-mark their environment with secretions from several glands, and the secretion of the submandibular cutaneous gland is strongly correlated with social status. Dominant, male rabbits have a higher secretory activity of the gland, and show much more scent-marking behaviour than do any other individuals within the social group. This study was principally conducted at Hope Farm, Cattai National Park in New South Wales, Australia.The proteinaceous components of the secretion varied between individuals, but the protein profile of an individual did not change over time.It was found that dominant rabbits chin mark preferentially at the entrances to warrens, and at the boundaries of their territory.The work in this study provides new insights into the way that rabbit semiochemical messages work. The difference between the secretion of a subordinate and a dominant rabbit appears to be due to the presence or absence of one compound, 2-phenoxy ethanol. This compound, with known fixative properties, supports the idea that the only difference between dominant and subordinate secretions is whether or not they persist in the environment after marking. Such a mechanism for asserting dominance may be much more common in mammals than is apparent from the published literature / Doctor of Philosophy (PhD)
82

Effects of queen mandibular pheromone on locomotor behaviour and learning in worker honey bees Apis mellifera

Vergoz, Vanina, n/a January 2008 (has links)
In a honey bee colony, the queen uses queen mandibular pheromone (QMP) to induce young worker bees to feed and groom her. Among its many behavioural and physiological effects, QMP reduces dopamine levels in the brains of young worker bees. Dopamine is a biogenic monoamine involved in numerous functions including motor control and aversive learning. This study investigates the effects of QMP on motor activities and aversive learning behaviour and the potential link between QMP and dopamine levels in the brain of young bees. In young bees under the age of 15-days, QMP dramatically reduced locomotor activity and inhibited aversive learning behaviour. Interestingly in older bees these behaviours were not affected by pheromone. Treating young bees with the dopamine precursor, L-dopa (3.25 [mu]g/mI), partially rescued the levels of locomotor activity in QMP-treated bees, and reduced QMP�s effects on aversive learning. This suggests that blocking effects of QMP on both locomotor activity and aversive learning result at least in part from QMP-induced changes in brain dopamine levels. Two components of the QMP blend, 4-hydroxy-3-methoxyphenylethanol (HVA) and methyl p-hydroxybenzoate (HOB) were examined more closely. Both HVA and HOB are structurally similar to dopamine. HVA was found to mimic the effects of the full QMP blend on aversive learning. Treating bees with HVA reduced aversive learning in young bees. In contrast, treatment with HOB did not affect learning ability. This strongly suggests that HVA is one of the key components that mediates the actions of QMP on aversive learning. The final section of this thesis investigates why it might be advantageous to honey bee queens to block aversive learning and reduce locomotor activity in young worker bees. The study reveals age-related differences in behaviours that individual worker bees display towards QMP. Young bees reared with QMP or collected from a queenright hive showed attraction to QMP. Conversely, older bees displayed avoidance behaviour towards QMP. By blocking the establishment of aversive memories, young bees may be prevented from forming an association between QMP and any unpleasant side effects induced by this pheromone. This may confer significant benefit to the queen by increasing the likelihood of young workers remaining in her attendance.
83

Responses of males to a pheromone blend of female Oriental fruit moth with and without E8, E10-dodecadien-1-ol, a peromone component of codling moth (Lepidoptera: Tortricidae)

Allred, Darin B. 18 April 1995 (has links)
Graduation date: 1995
84

Larval Release Rhythms and Larval Behavior of Palinurid Lobsters: a Comparative Study

Ziegler, Tracy Ann 28 November 2007 (has links)
This dissertation investigated larval release and larval behavior of the Caribbean spiny lobster Panulirus argus and the spotted spiny lobster P. guttatus. These species were examined under laboratory conditions to determine the phase relationship between larval release and natural environmental cycles. P. argus displayed a nocturnal tidal rhythm, while P. guttatus displayed a circadian rhythm in larval release. P. argus releases larvae near the time of nocturnal high slack water, while P. guttatus released larvae near the time of sunrise. The role of 'pumping pheromones' in controlling larval release behaviors was tested by measuring the pumping response of ovigerous P. argus to (1) hatch water, (2) homogenized-embryo water, (3) embryo-conditioned water, and (4) water containing homogenized-egg cases. Lobsters with late-stage embryos displayed increased pleopod pumping with increased concentration of hatch water. Water individually conditioned with homogenized late-stage embryos, intact late-stage embryos, and homogenized egg-cases induced pumping activity in females with late-stage embryos, indicating the presence of a chemical cue. I quantified pumping responses upon exposure to synthetic peptides to determine if they mimicked pheromones that induce larval release behaviors. Pumping behavior was evoked by oligopeptides with a basic amino acid at the carboxy-terminus, preceded by several neutral amino acids. Carboxyl-terminal arginine peptides serve as pheromone mimics. I investigated whether these peptides originate from the action of trypsin-like enzymes by conducting a bioassay measuring pumping activity of ovigerous P. argus subjected to increasing concentrations of trypsin, trypsin inhibitor, and a combination of the two. Pumping activity increased with increasing concentrations of trypsin and trypsin inhibitor, while behaviors ceased when ovigerous females were subjected to a complex of the two. Pheromones are generated by trypsin-like enzymes assisting in the degradation of the egg membranes at the time of hatching. Vertical swimming behaviors of stage-I phyllosoma larvae of P. argus and P. guttatus were observed under laboratory conditions. P. argus larvae displayed a pattern of twilight vertical migration, while P. guttatus larvae displayed nocturnal diel vertical migration (DVM). Rhythms persisted for 5-6 cycles under constant conditions, indicating that an endogenous rhythm in activity plays a proximate role in DVM for both species. / Dissertation
85

Odour Communication in Pieris Butterflies

Andersson, Johan January 2004 (has links)
No description available.
86

Swarm-based Area Exploration and Coverage based on Pheromones and Bird Flocks

Ventocilla, Elio January 2013 (has links)
Swarm Intelligence (SI) is a young field of study from which solutions to complex problems have been proposed based on how some natural organisms (e.g. ants, bees and others) achieve many of their daily tasks through simple sets of interactions. This thesis proposes two models for area exploration and coverage based on SI principles. These two models present a novel approach based on the combination of: ants’ pheromones, in order to keep track of visited places; and bird flocks or fish schooling, so as to move and collaborate. An implementation of both models was done in order to simulate and evaluate both the emergent behavior of the agents as well as their area exploration and coverage performance. Based on the outcome of the simulations it is concluded that both models are able to perform the exploration and coverage task and that one model is better than the other.
87

Attentional processes in mosquito-eating jumping spiders: search imagesand cross-modality priming

Cross, Fiona Ruth January 2009 (has links)
Evarcha culicivora, a species of jumping spider (Araneae: Salticidae from the Lake Victoria region of East Africa, has unusual prey-choice behaviour. It preferred prey is blood-carrying mosquitoes. It also has unusually complex mate-choice behaviour, with mutual mate choice being pronounced. This thesis is a study of E. culicivora’s prey-choice behaviour and mate-choice behaviour, as well as a study of processes underlying selective attention in this unusual species. E. culicivora uses olfaction in unique and often surprising ways. This includes identifying potential mates by odour alone, as well as choosing the odour of potential mates that have recently fed on blood-carrying mosquitoes. The odour of potential mates also primes both sexes for escalating conflict with potential rivals, as well as priming selective attention to the masked odour of specifically potential mates. Besides all this, the odour of blood-carrying mosquitoes primes E. culicivora to selectively attend to the masked odour of specifically this prey. Moreover, the appearance of blood-carrying mosquitoes and of potential mates primes E. culicivora to selectively attend to specifically the appearance of cryptic blood-carrying mosquitoes and cryptic potential mates, respectively. Vision and olfaction can even work together, with olfactory and visual cues from blood-carrying mosquitoes priming E. culicivora to selectively attend to the appearance and odour, respectively, of blood-carrying mosquitoes. Furthermore, E. culicivora has a poorly-understood relationship with two plant species, Lantana camara and Ricinus communis, and E. culicivora can identify these two plant species by odour alone. These plants may be relevant to this salticid as a nectar source by which it supplements its insect diet, but these plants may also be as sites at which E. culicivora males and females find potential mates, with E. culicivora’s interactions on these plants being especially exaggerated and complex.
88

Effects of queen mandibular pheromone on locomotor behaviour and learning in worker honey bees Apis mellifera

Vergoz, Vanina, n/a January 2008 (has links)
In a honey bee colony, the queen uses queen mandibular pheromone (QMP) to induce young worker bees to feed and groom her. Among its many behavioural and physiological effects, QMP reduces dopamine levels in the brains of young worker bees. Dopamine is a biogenic monoamine involved in numerous functions including motor control and aversive learning. This study investigates the effects of QMP on motor activities and aversive learning behaviour and the potential link between QMP and dopamine levels in the brain of young bees. In young bees under the age of 15-days, QMP dramatically reduced locomotor activity and inhibited aversive learning behaviour. Interestingly in older bees these behaviours were not affected by pheromone. Treating young bees with the dopamine precursor, L-dopa (3.25 [mu]g/mI), partially rescued the levels of locomotor activity in QMP-treated bees, and reduced QMP�s effects on aversive learning. This suggests that blocking effects of QMP on both locomotor activity and aversive learning result at least in part from QMP-induced changes in brain dopamine levels. Two components of the QMP blend, 4-hydroxy-3-methoxyphenylethanol (HVA) and methyl p-hydroxybenzoate (HOB) were examined more closely. Both HVA and HOB are structurally similar to dopamine. HVA was found to mimic the effects of the full QMP blend on aversive learning. Treating bees with HVA reduced aversive learning in young bees. In contrast, treatment with HOB did not affect learning ability. This strongly suggests that HVA is one of the key components that mediates the actions of QMP on aversive learning. The final section of this thesis investigates why it might be advantageous to honey bee queens to block aversive learning and reduce locomotor activity in young worker bees. The study reveals age-related differences in behaviours that individual worker bees display towards QMP. Young bees reared with QMP or collected from a queenright hive showed attraction to QMP. Conversely, older bees displayed avoidance behaviour towards QMP. By blocking the establishment of aversive memories, young bees may be prevented from forming an association between QMP and any unpleasant side effects induced by this pheromone. This may confer significant benefit to the queen by increasing the likelihood of young workers remaining in her attendance.
89

A sensory map of the odour world in the moth brain /

Carlsson, Mikael A., January 2003 (has links) (PDF)
Diss. (sammanfattning) Alnarp : Sveriges lantbruksuniv. / Härtill 5 uppsatser.
90

Semiochemicals and social signalling in the wild European rabbit (Oryctolagus cuniculus (L.)) /

Hayes, Richard Andrew. January 2000 (has links)
Thesis (Ph.D.) -- University of Western Sydney, Hawkesbury, 2000. / A thesis presented to the University of Western Sydney, Hawkesbury, in partial fulfilment of the requirements for the degree of Doctor of Philosophy, December, 2000. Includes bibliographical references.

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