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Omar A Shalaby

Ball State University, Biology, Associate Teaching Professor of Forensic Biology

American University of Science and Technology, Faculty of Health sciences, Department of Forensic sciences, Assistant professor of forensic biology

Beirut Arab University, Biological and Environmental Sciences, Faculty Member

Imam Abdulrahman bin Faisal University, Biology, Faculty Member

University of Maryland Global Campus, Biology and Natural Sciences, Adjunct Associate professor of Biological Sciences

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I am a forensic entomologist with a key focus on the application of natural sciences (entomology, and biology) to crime scene investigation.
Profoundly knowledgeable and resourceful Biologist/Zoologist/entomologist with over 30 years of research and university-level teaching experience. A bilingual exceptional communicator with exemplary written and verbal
skills in both English and Arabic. Innovative thinker with strong field and laboratory research skills and problem-solving capabilities.

FIELD OF SPECIALIZATION: Forensic Entomology — a field to be utilized by law authorities around the world, offers a great potential of studies and research that enable Forensic Entomologists to elevate their capabilities in crimes and drug abuse investigations of homicide and suicide cases.
Supervisors: M.Lee Goff and Hedayat Abdel Ghafar
Phone: 8083446276
Address: Department of Biology
College of Sciences and Humanities
Ball State University
Foundational Science Building, RM# 213
1600 Ashland Avenue
Muncie, IN 47306

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Papers by Omar A Shalaby

Mitochondrial DNA‑Based Identification of Developmental Stages and Empty Puparia of Forensically Important Flies (Diptera) in Egypt

Journal of forensic science and medicine, 2018

Relying on morphology in the estimation of postmortem intervalsis not always accurate for all lif... more Relying on morphology in the estimation of postmortem intervalsis not always accurate for all life phases of flies, especially for immature stages.
The present study demonstrates the application of cytochrome oxidase I sequences, a partial mitochondrial (mt) gene region, to differentiate
forensically important fliesinAlexandria, Egypt. Thirty‑three adult flies, larvae, and pupae were collected from rabbit carcasses. Nineteen were
used for genotyping. Sequence analysis revealed no significant intraspecific divergence in Diptera species. Accordingly, a neighbor-joining
tree using the Kimura 2‑parameter model illustrated reciprocal morphology between species. Specimens represented five species, four genera,
foursubfamilies, two families, and one order. We herein identify five different Diptera species, Chrysomya albiceps, Chrysomya megacephala,
Calliphora vicina, Lucilia sericata, and Ophyra capensis, using mt DNAas a species‑specific marker for identification in a local database set‑up.

Insects as Witness to Man’s Violent Strategies: Application to Forensic Science in Egypt

Variation on Arthropod Succession onto Exposed Rabbit Carrions in Different Seasons and Habitats Induced by Presence of Drugs and Toxins in Tissues

FORENSICALLY FLIES DETECT THE NUTRITIONAL VALUE OF CORPSES THROUGH NEURO-CHEMORECEPTIVE CELLS-(5TH CELL)

Animals have evolved several chemosensory systems for detecting potentially dangerous foods in th... more Animals have evolved several chemosensory systems for detecting potentially dangerous foods in the environment. Activation of specific sensory cells within these chemosensory systems usually elicits an aversive behavioral response, leading to avoidance of the noxious foods. Blowflies respond to sugars, salts and water through the activation of specific chemoreceptor neurons in the antennal, labellar and tarsal chemosensillae. These insects also detect deterrent stimuli with the so called fifth or deterrent cell. Using forensically important flies (blowflies) as a model organism, the question was if these flies have the ability to detect the nutritional value of corpses when injected with different doses of morphine. In the attempt to gain information on the mechanisms underlying reception of noxious and repellent compounds, electrophysiological and behavioral experiments have been performed to confirm the hypothesis that morphine sulfate has a repellent effect on fly attraction to corpse. Electrophysiological and behavioral results indicate that morphine sulfate activate the fifth cell in the chemosensillae. In field behavioral test, carrions injected with doses of morphine sulfate, are colonized later with flies than morphine-free carrions. This finding is in accordance with the spike frequency elevation observed for the fifth cell activity. The prevailing activation of the deterrent cell by morphine sulfate is directly coupled with a coherent behavioral output. Therefore, comparison of behavioral and electrophysiological data, affirm that blowfly identify morphine sulfate as a deterrent stimuli by activation of the fifth cell.

Electrophysiological responses of chemoreceptor neurons in Calliphora vicina (Diptera: Calliphoridae) to morphine sulphate and its implications to forensic entomology.

The major task of a forensic entomologist is to determine an accurate post-mortem interval (PMI) ... more The major task of a forensic entomologist is to determine an accurate post-mortem interval (PMI) by analyzing the development or succession of necrophagous insects and other arthropods on the carcass. Blow flies (Diptera: Calliphoridae) are the first arrivals at a death scene. Flies are attracted to carcasses through volatile compounds emitted during different stages of decomposition. It is therefore probable that flies can easily distinguish between the chemical signatures of early and late decay stages. In order to locate the remains, flies are equipped with excellent sensory organs to detect chemical cues being produced by corpse decomposition. For many insects, the chemical senses (olfactory or gustatory) play a major role in decisions regarding feeding, oviposition, and other behaviours. So the purpose of this study was to investigate the electrophysiological responses of receptor neurons on the antennae, labium, and tarsus of a forensically important blowfly (Calliphora vicina) to different doses of morphine in decomposing tissues as well as odours emitted from the underneath soil. This study reveals that morphine has a repellent effect with significant differences in the degree of sensitivity between different stimulating sites, and these conclusions should be considered when estimating PMI, or an underestimation will result.

Variations in the blow- and flesh flies succession on rabbit carrions killed by different methods.

Seasonal field variations of arthropod development and succession, on exposed rabbit carcasses induced by propoxur in a semi desert region in Egypt

Seasonal field studies were carried out on exposed rabbit carrion, killed by different doses of a... more Seasonal field studies were carried out on exposed rabbit carrion, killed by different doses of a commonly used insecticide named propoxur, It was noted that the duration of the decompositional stages were directly related to the yearly temperature changes and the doses of the insecticide used. Rabbit carcasses which had been killed by variable doses of propoxur, showed markedly pronounced prolongation of the decompositional stages. This prolongation was more pronounced during the cooler seasons. Also, using the propoxur induced several noticeable differences either in succession pattern of the carrion breeding flies or in the rate of development of their immature stages. As to rabbits killed by high concentration of propoxur, calliphorids and sarcophagids arrived later and the rate of development of their maggots were retarded in comparison with the control carcasses, this retardation was more obvious in cooler seasons. A difference in insect composition was observed as a result of the dose of the insecticide used at a specific season. It should be pointed out that the presence of this insecticide alters the successional model in this area. Several species were absent in such carcasses. In addition, some carcasses attracted other species, which were not observed on the corresponding control carcasses.

Trophic interaction of carrion-attendant arthropods in a botanical garden in Alexandria, Egypt.

Comparison of patterns of decomposition in a hanging carcass and a carcass in contact with soil in a xerophytic habitat on the Island of Oahu, Hawaii.

Decomposition studies were conducted to determine differences in rates and patterns of decomposit... more Decomposition studies were conducted to determine differences in rates and patterns of decomposition of carcasses hanging and exposed on the surface of the soil. These studies were conducted between 17 October and 17 December 1997 inside of Diamond Head Crater on the island of Oahu, Hawaii. The animal model was the domestic pig. Sus scrofa. The rate of biomass removal from the hanging carcass was significantly slower than that observed for the control carcass during the bloat and decay stages of decomposition. Internal temperatures for the control carcass were elevated above the ambient air temperatures during the earlier stages of decomposition (bloated and decay), while those recorded for the hanging carcass approximated the ambient air temperatures. There was a greater diversity of arthropod species recorded and numbers of individuals observed were higher for the control carcass. A significant site of arthropod activity was observed on the surface of the soil immediately under the hanging carcass and this became the primary site of arthropod activity as decomposition progressed.

Talks by Omar A Shalaby

Insect and other Arthropod Succession onto Exposed Rabbit Carrions in Different Seasons Induced by the Presence of Toxins in Tissues: Applications to Forensic Entomology

Conference: Insect and other Arthropod Succession onto Exposed Rabbit Carrions in Different Seaso... more Conference: Insect and other Arthropod Succession onto Exposed Rabbit Carrions in Different Seasons Induced by the Presence of Toxins in Tissues: Applications to Forensic Entomology, Proceedings of the 2nd Egyptian International Congress of Medical& Forensic Sciences (13–15 February 2007), J. W. Marriott, Cairo, Egypt.

Mitochondrial DNA‑Based Identification of Developmental Stages and Empty Puparia of Forensically Important Flies (Diptera) in Egypt

Journal of forensic science and medicine, 2018

Relying on morphology in the estimation of postmortem intervalsis not always accurate for all lif... more Relying on morphology in the estimation of postmortem intervalsis not always accurate for all life phases of flies, especially for immature stages.
The present study demonstrates the application of cytochrome oxidase I sequences, a partial mitochondrial (mt) gene region, to differentiate
forensically important fliesinAlexandria, Egypt. Thirty‑three adult flies, larvae, and pupae were collected from rabbit carcasses. Nineteen were
used for genotyping. Sequence analysis revealed no significant intraspecific divergence in Diptera species. Accordingly, a neighbor-joining
tree using the Kimura 2‑parameter model illustrated reciprocal morphology between species. Specimens represented five species, four genera,
foursubfamilies, two families, and one order. We herein identify five different Diptera species, Chrysomya albiceps, Chrysomya megacephala,
Calliphora vicina, Lucilia sericata, and Ophyra capensis, using mt DNAas a species‑specific marker for identification in a local database set‑up.

Insects as Witness to Man’s Violent Strategies: Application to Forensic Science in Egypt

Variation on Arthropod Succession onto Exposed Rabbit Carrions in Different Seasons and Habitats Induced by Presence of Drugs and Toxins in Tissues

FORENSICALLY FLIES DETECT THE NUTRITIONAL VALUE OF CORPSES THROUGH NEURO-CHEMORECEPTIVE CELLS-(5TH CELL)

Animals have evolved several chemosensory systems for detecting potentially dangerous foods in th... more Animals have evolved several chemosensory systems for detecting potentially dangerous foods in the environment. Activation of specific sensory cells within these chemosensory systems usually elicits an aversive behavioral response, leading to avoidance of the noxious foods. Blowflies respond to sugars, salts and water through the activation of specific chemoreceptor neurons in the antennal, labellar and tarsal chemosensillae. These insects also detect deterrent stimuli with the so called fifth or deterrent cell. Using forensically important flies (blowflies) as a model organism, the question was if these flies have the ability to detect the nutritional value of corpses when injected with different doses of morphine. In the attempt to gain information on the mechanisms underlying reception of noxious and repellent compounds, electrophysiological and behavioral experiments have been performed to confirm the hypothesis that morphine sulfate has a repellent effect on fly attraction to corpse. Electrophysiological and behavioral results indicate that morphine sulfate activate the fifth cell in the chemosensillae. In field behavioral test, carrions injected with doses of morphine sulfate, are colonized later with flies than morphine-free carrions. This finding is in accordance with the spike frequency elevation observed for the fifth cell activity. The prevailing activation of the deterrent cell by morphine sulfate is directly coupled with a coherent behavioral output. Therefore, comparison of behavioral and electrophysiological data, affirm that blowfly identify morphine sulfate as a deterrent stimuli by activation of the fifth cell.

Electrophysiological responses of chemoreceptor neurons in Calliphora vicina (Diptera: Calliphoridae) to morphine sulphate and its implications to forensic entomology.

The major task of a forensic entomologist is to determine an accurate post-mortem interval (PMI) ... more The major task of a forensic entomologist is to determine an accurate post-mortem interval (PMI) by analyzing the development or succession of necrophagous insects and other arthropods on the carcass. Blow flies (Diptera: Calliphoridae) are the first arrivals at a death scene. Flies are attracted to carcasses through volatile compounds emitted during different stages of decomposition. It is therefore probable that flies can easily distinguish between the chemical signatures of early and late decay stages. In order to locate the remains, flies are equipped with excellent sensory organs to detect chemical cues being produced by corpse decomposition. For many insects, the chemical senses (olfactory or gustatory) play a major role in decisions regarding feeding, oviposition, and other behaviours. So the purpose of this study was to investigate the electrophysiological responses of receptor neurons on the antennae, labium, and tarsus of a forensically important blowfly (Calliphora vicina) to different doses of morphine in decomposing tissues as well as odours emitted from the underneath soil. This study reveals that morphine has a repellent effect with significant differences in the degree of sensitivity between different stimulating sites, and these conclusions should be considered when estimating PMI, or an underestimation will result.

Variations in the blow- and flesh flies succession on rabbit carrions killed by different methods.

Seasonal field variations of arthropod development and succession, on exposed rabbit carcasses induced by propoxur in a semi desert region in Egypt

Seasonal field studies were carried out on exposed rabbit carrion, killed by different doses of a... more Seasonal field studies were carried out on exposed rabbit carrion, killed by different doses of a commonly used insecticide named propoxur, It was noted that the duration of the decompositional stages were directly related to the yearly temperature changes and the doses of the insecticide used. Rabbit carcasses which had been killed by variable doses of propoxur, showed markedly pronounced prolongation of the decompositional stages. This prolongation was more pronounced during the cooler seasons. Also, using the propoxur induced several noticeable differences either in succession pattern of the carrion breeding flies or in the rate of development of their immature stages. As to rabbits killed by high concentration of propoxur, calliphorids and sarcophagids arrived later and the rate of development of their maggots were retarded in comparison with the control carcasses, this retardation was more obvious in cooler seasons. A difference in insect composition was observed as a result of the dose of the insecticide used at a specific season. It should be pointed out that the presence of this insecticide alters the successional model in this area. Several species were absent in such carcasses. In addition, some carcasses attracted other species, which were not observed on the corresponding control carcasses.

Trophic interaction of carrion-attendant arthropods in a botanical garden in Alexandria, Egypt.

Comparison of patterns of decomposition in a hanging carcass and a carcass in contact with soil in a xerophytic habitat on the Island of Oahu, Hawaii.

Decomposition studies were conducted to determine differences in rates and patterns of decomposit... more Decomposition studies were conducted to determine differences in rates and patterns of decomposition of carcasses hanging and exposed on the surface of the soil. These studies were conducted between 17 October and 17 December 1997 inside of Diamond Head Crater on the island of Oahu, Hawaii. The animal model was the domestic pig. Sus scrofa. The rate of biomass removal from the hanging carcass was significantly slower than that observed for the control carcass during the bloat and decay stages of decomposition. Internal temperatures for the control carcass were elevated above the ambient air temperatures during the earlier stages of decomposition (bloated and decay), while those recorded for the hanging carcass approximated the ambient air temperatures. There was a greater diversity of arthropod species recorded and numbers of individuals observed were higher for the control carcass. A significant site of arthropod activity was observed on the surface of the soil immediately under the hanging carcass and this became the primary site of arthropod activity as decomposition progressed.

Insect and other Arthropod Succession onto Exposed Rabbit Carrions in Different Seasons Induced by the Presence of Toxins in Tissues: Applications to Forensic Entomology

Conference: Insect and other Arthropod Succession onto Exposed Rabbit Carrions in Different Seaso... more Conference: Insect and other Arthropod Succession onto Exposed Rabbit Carrions in Different Seasons Induced by the Presence of Toxins in Tissues: Applications to Forensic Entomology, Proceedings of the 2nd Egyptian International Congress of Medical& Forensic Sciences (13–15 February 2007), J. W. Marriott, Cairo, Egypt.