Impact of Marabunta ants on post-mortem interval estimation in pigs: Insights from Okuku, Nigeria
Cletus Obun BSc, MSc, PhD
Department of Anatomy and Forensic Anthropology, Faculty of Basic Medical Sciences, University of Cross River, Okuku, Nigeria
Search for more papers by this authorCorresponding Author
Darlington Nnamdi Onyejike BSc, MSc, MBA, PhD
Department of Forensic Medicine, School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria
Correspondence
Darlington Nnamdi Onyejike, Department of Forensic Medicine, School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa.
Email: [email protected]
Search for more papers by this authorUgochukwu Godfrey Esomonu BSc, MSc, PhD
Department of Anatomy and Forensic Anthropology, Faculty of Basic Medical Sciences, University of Cross River, Okuku, Nigeria
Search for more papers by this authorOgugua Augustine Egwu BSc, MSc, PhD
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria
Department of Anatomy, Alex Ekwueme Federal University, Ndufu-Alike, Ikwo, Nigeria
Search for more papers by this authorChiwendu Modesta Dimkpa BSc
Department of Anatomy and Forensic Anthropology, Faculty of Basic Medical Sciences, University of Cross River, Okuku, Nigeria
Search for more papers by this authorCletus Obun BSc, MSc, PhD
Department of Anatomy and Forensic Anthropology, Faculty of Basic Medical Sciences, University of Cross River, Okuku, Nigeria
Search for more papers by this authorCorresponding Author
Darlington Nnamdi Onyejike BSc, MSc, MBA, PhD
Department of Forensic Medicine, School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria
Correspondence
Darlington Nnamdi Onyejike, Department of Forensic Medicine, School of Laboratory Medicine and Medical Sciences, University of KwaZulu-Natal, Durban, South Africa.
Email: [email protected]
Search for more papers by this authorUgochukwu Godfrey Esomonu BSc, MSc, PhD
Department of Anatomy and Forensic Anthropology, Faculty of Basic Medical Sciences, University of Cross River, Okuku, Nigeria
Search for more papers by this authorOgugua Augustine Egwu BSc, MSc, PhD
Department of Anatomy, Faculty of Basic Medical Sciences, Nnamdi Azikiwe University, Nnewi, Nigeria
Department of Anatomy, Alex Ekwueme Federal University, Ndufu-Alike, Ikwo, Nigeria
Search for more papers by this authorChiwendu Modesta Dimkpa BSc
Department of Anatomy and Forensic Anthropology, Faculty of Basic Medical Sciences, University of Cross River, Okuku, Nigeria
Search for more papers by this authorAbstract
The rising homicide rates in Nigeria underscore the necessity for comprehensive post-mortem interval (PMI) estimations to enhance the reliability of forensic investigations. This study investigates the impact of Marabunta ants (Hymenoptera: Formicidae) on the decomposition process and PMI estimation in pig carcasses during the wet season in Okuku, Nigeria. Using two juvenile domestic pigs, we employed a controlled experimental approach at the Department of Anatomy and Forensic Anthropology Research Facility. The study spanned 30 days, with systematic observations of postmortem changes, insect activity and environmental conditions recorded at specified intervals. Results indicated pronounced effects of Marabunta ants on decomposition dynamics. Notably, the presence of these ants altered the expected insect succession patterns, delaying the colonisation by blowflies, which typically dominate the initial decay stages. By the second day, marked ant activity was observed, leading to distinct bite marks on the carcasses, while the other carcasses exhibited standard decomposition without any interference. Accumulated degree days (ADD) and total body scores (TBS) demonstrated a parabolic relationship, revealing rapid initial decay followed by a stabilisation phase as skeletonisation progressed. This research confirms that environmental conditions and insect activities significantly influence decomposition rates and PMI estimations. The findings suggest a need for forensic practitioners to recognise the role of Marabunta ants in decay processes and the potential misinterpretations of ant-induced marks as perimortem injuries. Future studies should explore seasonal variations in decomposition and insect succession to refine forensic entomological methodologies.
CONFLICT OF INTEREST STATEMENT
The authors have no conflicts of interest to declare.
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