The taphonomic effects of long-term burial in the South African Highveld

Taphonomy studies the environmental effects on remains from the time of deposition to the time of recovery and has been integrated into the field of forensic anthropology. The changes to skeletal remains are dependent on the method of disposal and the surrounding environment. This study focused on buried remains where the type and chemical composition of the soil and the microorganisms present need to be considered. The aim was to investigate the type, frequency, and correlations of the taphonomic alterations of buried domestic pigs. Six taphonomic alterations were observed which included depositional staining, adipocere formation, bone weathering, acidic soil corrosion, and plant, and animal activity. Depositional staining, weathering and plant activity were the most common alterations followed by adipocere which was present on 92.3% of the remains. The bones were mostly stained dark brown and brown; however, the trunk region was the only region to present with black staining. The right sides were darker than the left due to the body positioning as most pigs were placed on their right sides and thus were in direct contact with the cadaver decomposition island. Additionally, the right sides presented with more adipocere as well as increased plant activity suggesting that the soil retained water. Darker stains were correlated with a more complete skeleton as adipocere provides some protection. The study confirms that there are various complicated relationships between different taphonomic alterations. A good understanding of them is needed in forensic anthropology to assist in reconstructing the events that occur after death.

A Review of the Impacts and Opportunities for African Urban Dragonflies

Simple Summary

The expansion of urban areas in combination with climate change places great pressure on species found in freshwater habitats. Dragonflies are iconic freshwater organisms due to their large body sizes and striking coloration. They have been widely used to indicate the impacts of natural and human-mediated activities on freshwater communities, while also indicating the mitigation measures required to ensure their conservation. Here, we review the major threats to dragonflies in southern Africa, specifically those in urban areas. We also provide information on effective mitigation measures to protect dragonflies and other aquatic insects in urban spaces. Using three densely populated areas as case studies, we highlight some of the greatest challenges for dragonflies in South Africa. More importantly, we give a summary of current mitigation measures which have maintained dragonflies in urban spaces. In addition to these mitigation measures, public involvement and raising awareness contribute greatly to the common cause of protecting dragonflies around us.

Abstract

Urban settlements range from small villages in rural areas to large metropoles with densely packed infrastructures. Urbanization presents many challenges to the maintenance of freshwater quality and conservation of freshwater biota, especially in Africa. There are many opportunities as well, particularly by fostering contributions from citizen scientists. We review the relationships between dragonflies and urbanization in southern Africa. Shifts in dragonfly assemblages indicate environmental change, as different species are variously sensitive to abiotic and biotic water and bank conditions. They are also conservation umbrellas for many other co-occurring species. Major threats to southern African dragonflies include increasing infrastructure densification, frequent droughts, habitat loss, pollution, and invasive alien vegetation. Mitigation measures include implementation of conservation corridors, maintenance of healthy permanent ponds, pollution reduction, and removal of invasive alien trees. Citizen science is now an important approach for supplementing and supporting professional scientific research.