Among the 49 taxa were 37 native species and 12 non-native species not known to have naturalised, while a survey of South African nurseries and online plant retailers found 32 of the recommended taxa commercially available. The case study was developed for the City of Cape Town Metropolitan Municipality, where the need for safer replacement planting is immediate. Polyphagous shot hole borer, or PSHB, was first detected in the city in 2019.

By March 2025, more than 10,000 trees had been infested and approximately 4,000 affected trees had been removed from public land, according to the City of Cape Town Invasive Species Unit. The municipality’s tree canopy covers only about 6% of its area, and further losses could accompany urban expansion, infrastructure development, climate change and pest damage. Although the inventory and protocol describe planning conditions, they do not test whether the selected trees will prevent infestations or invasions; they provide a transparent way to classify candidate species and identify where planting, removal and monitoring are warranted.

The protocol begins with a comprehensive inventory of every tree taxon known to occur in a study region, including trees in natural, semi-natural, urban and cultivated settings. A second list then identifies which taxa are already planted locally. The Cape Town analysis drew on a South African inventory containing more than 35,000 records of 805 planted tree taxa.

By considering only taxa already established in the country, the researchers avoided actively recommending new introductions, which would require separate screening for unforeseen invasion potential. Each candidate is then evaluated against criteria chosen for the local ecological, regulatory and management context. The first principal criterion in the Cape Town case was regulatory status: taxa listed under South Africa’s National Environmental Management: Biodiversity Act alien and invasive species regulations cannot be planted unless the relevant environmental authority grants a permit or exemption.

The authors also advise consulting local practitioners because official lists may not identify emerging or localised invasions. The second criterion concerned PSHB host status. A Neocosmospora-colonised host permits transmission of the fungus but does not support reproduction of the beetle.

A competent host supports the establishment of a natal gallery and production of offspring. A kill-competent host has at least one documented individual that died from the combined effects of the beetle and fungus infestation. The researchers integrated several independent datasets rather than relying on a single source.

South Africa’s 2020 regulatory lists established legal status, while a national planted-tree inventory classified taxa as native or non-native. The Global Naturalised Alien Flora database supplied evidence of naturalisation within and outside South Africa. A global PSHB host list, compiled using molecular records confirming the beetle’s identity, and host-status information were used to assess susceptibility.

To avoid underestimating potential risk, taxa with unknown statuses were conservatively assigned the highest known risk level among their congeners. Cross-referencing these attributes produces eight recommendations grouped into scenarios involving tree planting, tree removal and tree monitoring. Taxa regulated as invasive fall into the most restrictive category and must not be planted without authorisation.

Naturalised kill-competent hosts should not be selected for planting; where a site is close to a PSHB-infested or ecologically sensitive area, their removal is recommended where feasible. Native kill-competent hosts and naturalised competent hosts are also unsuitable for planting in relevant situations, while less severe combinations may be considered only with restrictions on scale, site choice or continued monitoring. Outside infestation and sensitive zones, the protocol prioritises taxa that are not known hosts and have no evidence of naturalisation.

These recommendations encode precautionary assumptions rather than demonstrated outcomes, and uncertainty requires consultation of global and region-specific evidence. Among the 444 planted taxa assessed for Cape Town, 85, or 19%, were regulated as invasive and could not be planted without permission. Nine were kill-competent hosts, five of them non-native and naturalised.

Another 57 were competent hosts and were predominantly non-native and naturalised. Beyond confirmed hosts, 81 taxa belonged to genera containing competent hosts, while 68 were Neocosmospora-colonised hosts. Of the 115 taxa not known to be PSHB hosts or closely related to known hosts, 66 were non-native and naturalised and were therefore not recommended for planting under the central scenario.

The final set of 49 included native taxa such as Dais cotinifolia, the pom pom tree, and Aloidendron dichotomum, the quiver tree, as well as non-native taxa not known to have naturalised. Commercial availability may determine how readily the protocol can influence planting programmes. Searches of a representative selection of printed nursery catalogues, public online plant retailers and targeted South African sales queries showed that 32 of the 49 recommended taxa were offered as seeds, seedlings, saplings or mature trees; 29 of those available taxa were native.

The findings therefore identify a gap between ecological screening and horticultural supply. They do not show that commercially available species are inherently less secure than unavailable ones. Rather, the authors propose using the screened list to encourage nurseries to propagate suitable alternatives and help municipalities and public buyers identify lower-risk options.

Lists can also be tailored to particular functions, such as street planting, riparian buffers or allergen-free school environments, and should be reviewed as evidence changes. Several limitations prevent the output from being treated as universally applicable. The underlying national inventory does not include every tree planted in South Africa or taxa that have never been trialled, so potentially suitable species may be absent because they are poorly represented in the available data.

Global and citizen-science databases can be incomplete, inconsistently standardised or locally unverified, while some regions lack the institutional capacity for taxonomic verification and pest surveillance. Native status alone does not eliminate all risks: habitat disturbance, propagule pressure and local environmental conditions can permit native trees to expand beyond their normal range. Factors such as prolific seed production, long-distance dispersal, clonal reproduction and vigorous resprouting may also require assessment.

Municipal or provincial application can incorporate climate, soils, nearby populations and provincial rules that differ under national regulations. The authors also stress that PSHB host knowledge is a temporal snapshot. Because the beetle is relatively recent in South Africa and Australia, some tree taxa may have had insufficient exposure for colonisation to be recorded, creating what the authors describe as host debt.

The known host range can expand as the invasion unfolds, requiring periodic review, long-term surveillance and adaptive management. Visual inspections can look for staining around entry holes, sawdust-like frass, gumming and discoloration, while baited traps, community reporting and regional networks may improve early detection. The protocol is intended to be transferred by replacing Cape Town datasets with local inventories, regulations and pest-host records, adding criteria such as drought tolerance or fire susceptibility where relevant.

Its value lies in making the evidence, exclusions and uncertainties behind tree-selection decisions visible rather than in claiming that a static list can guarantee ecological security.

Subject of Research: Evidence-based screening of tree taxa for invasive-species and shot hole borer risks

Article Title: An evidence-based protocol for developing lists for tree planting

Article References: Potgieter, L. J., Cadotte, M. W., Kumschick, S., Paap, T., Roets, F., Wilson, J. R. U., & Richardson, D. M. (2025). An evidence-based protocol for developing lists for tree planting. NeoBiota, 104, 113-137. https://doi.org/10.3897/neobiota.104.156206

Image Credits: AI Generated

DOI: 10.3897/neobiota.104.156206

Keywords: tree planting, biological invasions, polyphagous shot hole borer, species selection, Cape Town, urban forestry, pest risk, tree nurseries, ecological resilience, evidence-based, protocol, developing

The scale of the global challenge is enormous. Around 3.5 billion people lack access to safely managed sanitation, and more than half of them live in rapidly expanding urban areas. In sub-Saharan Africa, over 60 percent of urban dwellers reside in areas without the infrastructure to provide sanitation services. Informal settlements like BM Section, which packs roughly 14,000 residents onto 32.42 hectares of land owned by the City of Cape Town, illustrate the dilemma: land tenure is insecure, housing is overcrowded and precarious, and unemployment is high, making conventional sewered sanitation technically and politically difficult to deliver.

Container based sanitation works by capturing excreta in sealable containers that are transported to semi-centralised facilities for treatment. The technology ranges from small portable toilets resembling camping equipment to larger units moved by vehicles, and the World Health Organization and UNICEF’s Joint Monitoring Programme classify it as improved sanitation that can count as safely managed when appropriately serviced. In BM Section, the City of Cape Town provides household container based sanitation in the form of portable flush toilets, known locally as pota-pota, consisting of a toilet seat and two detachable storage cartridges used in rotation. A private contractor is supposed to collect filled cartridges three times a week and return clean ones directly to each household.

The research team, led by Mmeli Dube of the University of the Western Cape and Dani Barrington of the University of Western Australia, used a participatory method called Photovoice, in which thirteen residents were given disposable cameras and asked to photograph their sanitation experiences. The photographs then served as prompts during in-depth interviews, allowing participants to document conditions that conventional interviews often miss. Participants were purposively selected along axes of gender, disability, income and exposure to shocks such as flooding and fire, with roughly half using household portable flush toilets and half relying on shared sanitation. The team analysed the material using Winkler’s five normative contents of the Human Right to Sanitation, namely availability, accessibility, affordability, safety and acceptability, combined with Crenshaw’s theory of intersectionality.

The findings on shared sanitation were stark. Chemical and container toilets are notionally shared among five households, but residents reported that the real ratios are far higher, and public ablution blocks serving hundreds of people sometimes had only one working toilet out of five on the female side. Keli, a middle-aged unemployed mother, described a chemical toilet 100 metres from her home that was sometimes full of maggots, unstable in the wind, and fitted with a door that would not close properly, exposing users to passers-by. Because the toilet offered so little privacy during daylight hours, she resorted to using it at night, despite the risks of robbery and sexual assault that she said were frequently reported in her area.

Other participants had fared even worse. Bonani, an unemployed woman with care responsibilities, gave up on the shared toilet entirely after conflicts over keys, which were hoarded by more socially powerful residents who changed the locks and distributed keys only to people they preferred. She now practices open defecation in a field with her children, navigating flooded paths and fearing snakes, assault and the stigma of managing menstruation without any disposal facilities. Mila, who uses an ablution block, reported contracting an infection she traced to the filthy, blocked toilets, and at night she urinates and defecates in a bucket that she empties into a drain. The researchers found that exclusion from sanitation was not only a consequence of individual vulnerabilities but also of unequal power relations governing access to infrastructure.

Household portable flush toilets performed better in some respects, but only for those with the resources to adapt them. Sihle, a 60-year-old partially blind woman, described how her life improved when she received a pota-pota, which her son-in-law sheltered in a repurposed storage cubicle next to her shack. With a phone torch to light her way, she could use the toilet safely at night without depending on anyone. Yet her story is the exception. John, who has lived with disability since childhood and has a paralysed left arm, could not use his household toilet safely because it stood unsheltered on uneven ground, forcing him to balance by holding onto the sides of adjacent shacks. For him, a shared toilet with a solid structure was actually more acceptable than his own household facility.

The study’s central insight is that the technology’s benefits depend entirely on users’ capacity to adapt it, what the researchers describe as a form of implicit infrastructure in which residents complete or compensate for infrastructural shortcomings through their own labour and money. To make a portable flush toilet private, safe and dignified, users must build secure cubicles, level the ground, install locks, acquire torches, and rebuild after fires or floods. Lizwe, a young man with memory loss and eyesight problems living with seven family members, kept the family toilet in an unlocked storeroom where strangers used it without permission, and his household avoided flushing to delay filling the 16-litre cartridge, pushing waste down with broomsticks instead. When cartridges became too heavy, contractors refused to collect them, and residents carried them to the roadside themselves.

These adaptations carry serious hygiene consequences. When servicing schedules are not observed and cartridges fill faster than collections allow, users improvise by restricting toilet use to emergencies, emptying waste into drains, or resorting to shared facilities, all of which increase the likelihood of human contact with excreta and environmental contamination. The researchers calculate that a household of six, given typical excreta volumes of about 1.5 litres per person per day plus flushing water and toilet paper, could fill a standard cartridge in a single day. This complicates the classification of household container based sanitation as safely managed, because that classification assumes a level of servicing and user capacity that the reality on the ground does not support.

The authors conclude that technical provision alone is insufficient to realise the Human Right to Sanitation, and that policy and scholarship must incorporate intersectional and rights-based approaches if container based sanitation is to bring users closer to that right. In BM Section, a toilet delivered free of charge still fails the woman who cannot reach it safely, the disabled man who cannot sit on it, and the family that cannot lock it. As informal settlements grow and container based sanitation shifts from transitional fix to permanent reality by default, the study warns that monitoring frameworks based on facility type alone risk obscuring exactly the disparities in dignity, safety and access that human rights law was written to eliminate.

Subject of Research: Container based sanitation and the Human Right to Sanitation in a South African informal settlement

Article Title: Achieving the Human Right to Sanitation? Container based sanitation and intersectional vulnerabilities in a South African informal settlement

Article References: Dube, M., Anciano, F., Ofori, A. D., Mabaso, L., & Barrington, D. J. (2026). Achieving the Human Right to Sanitation? Container based sanitation and intersectional vulnerabilities in a South African informal settlement. PLOS Water, 5(10), e0000524. https://doi.org/10.1371/journal.pwat.0000524

Image Credits: AI Generated

DOI: 10.1371/journal.pwat.0000524

Keywords: sanitation, container based sanitation, informal settlements, human rights, Cape Town, intersectionality, Photovoice, portable flush toilets, Khayelitsha, water and sanitation, public health, urban inequality

Minjin’s path to national recognition has been shaped by a combination of rigorous research and determined advocacy. She is a resident researcher associated with the American Museum of Natural Heritage in New York, an affiliation that has allowed her to bridge the worlds of Mongolian field palaeontology and major international research institutions. At the same time, she is the founder of the Institute for the Study of Mongolian Dinosaurs in Umnugovi, in the Gobi region of southern Mongolia, where many of the country’s most celebrated Cretaceous fossils have been unearthed. The institute works at the intersection of science, education and community engagement, bringing dinosaur-themed science directly to the communities that live alongside some of the world’s most productive fossil beds.

Among the achievements cited in connection with her honours is her role in recovering and repatriating Mongolian dinosaur fossils that were being illegally exported. The most notable of these cases involved a skeleton of Tarbosaurus bataar, a large tyrannosaurid theropod closely related to Tyrannosaurus rex that roamed the Gobi Desert roughly 70 million years ago. Tarbosaurus is known almost exclusively from Mongolia and neighbouring regions of Asia, which makes specimens of the genus part of Mongolia’s irreplaceable natural patrimony. The repatriation of such a skeleton was more than a legal victory; it was a statement that fossils taken without permission from their country of origin can, with persistence and international cooperation, be returned home.

For her earlier work on fossil recovery and repatriation, Minjin had already received Mongolia’s Polar Star medal, one of the nation’s longstanding state decorations. The new state honour medal awarded this September therefore marks a second national acknowledgement of her contribution, underscoring how central fossil protection has become to Mongolia’s cultural and scientific policy. Fossil trafficking has long been a serious concern in countries with rich vertebrate-bearing sediments, because illegally collected specimens are frequently stripped of their geological and stratigraphic context, the very information that allows scientists to reconstruct ancient ecosystems. When fossils are looted, science loses data even when the bones themselves survive; when they are repatriated with their histories documented, both the nation and the research community recover something of what was lost.

Minjin’s influence extends beyond specimen recovery into the realm of public science. Her work to expand dinosaur-themed science in Mongolia has included educational programming designed to reach young audiences in a country where palaeontology was historically dominated by foreign expeditions. By establishing a research and education presence in Umnugovi, close to the fossil localities themselves, she has helped ensure that the economic and intellectual benefits of dinosaur discoveries flow, at least in part, to local communities. This model, in which local scientists lead research and outreach in their own country, has become an increasingly important touchstone in global discussions about who owns, studies and communicates the deep past.

International audiences will soon have the opportunity to hear Minjin describe this work first-hand. Delegates attending the 7th International Palaeontology Congress in Cape Town can learn more from her experiences as a keynote speaker in the Communicating Palaeosciences Symposium, scheduled for 2 December 2026. In her address, she will share insights into how she helped build awareness around Mongolia’s dinosaur heritage, drawing on nearly two decades of experience at the front lines of fossil protection, repatriation and public education. Her perspective is expected to resonate with researchers and communicators grappling with similar questions of heritage, access and equity in other fossil-rich nations.

The Communicating Palaeosciences Symposium, within which Minjin’s keynote will sit, is designed to bring together researchers and science communicators from across the world to explore how fossils, human evolution and the deep past can be communicated beyond traditional academic audiences. The premise of the symposium is that palaeontology’s stories, extinction, deep time, evolution and the origins of humanity, are among the most powerful in all of science, yet they are frequently conveyed through channels that fail to reach, or fail to respect, the communities most connected to the fossils themselves. Conveners of the symposium argue that the discipline must become more deliberate about how, and to whom, it speaks.

Science communication expert Dr Marina Joubert of Stellenbosch University in South Africa, the symposium convenor, framed the event’s ambitions in terms of inclusion and social relevance. “We will be focusing on how palaeontology is communicated to the public – and how it can become more inclusive, culturally sensitive and relevant to society,” she says. Her co-convener, Professor Anusuya Chinsamy-Turan of the University of Cape Town, who also chairs the organising committee of the 7th International Palaeontology Congress, emphasised the practical goal of the gathering. “Through our engagement with palaeontologists actively engaged in science communication, we hope to uncover good practices and strategies for more effective communication,” she says. Together, the two conveners have assembled a programme that treats communication not as an afterthought to research but as a skill and a responsibility in its own right.

The topics on the symposium agenda reflect the breadth of that ambition. Sessions will address ways to decolonise palaeontology, examining how the discipline’s history of extraction and foreign domination can be confronted and reimagined; misinformation in palaeoanthropology, a growing concern in an era when human-origins claims spread rapidly online; children’s natural-history education, which shapes the next generation of scientists and citizens; and the use of museums and exhibitions to spark public curiosity about the deep past. During the symposium, Dr Frederick Manthi of the National Museums of Kenya will also deliver a keynote address, focusing on the promotion of palaeoscience in Africa through the Kenyan experience, a national story of hominin discoveries, museum development and public engagement that parallels Minjin’s Mongolian narrative in instructive ways.

The Communicating Palaeosciences Symposium at IPC7 is presented with support from the Palaeontological Scientific Trust (PAST) and the South African Department of Science, Technology and Innovation (DSTI), partnerships that signal institutional commitment to public engagement as a core function of the palaeosciences. For Minjin, the Cape Town keynote will be an opportunity to place Mongolia’s experience within a global conversation: a demonstration that fossil protection, repatriation and community-centred education are not local curiosities but transferable strategies. Her state honour medal, awarded by her president and dedicated to her supporters, stands as evidence that governments increasingly recognise what the symposium’s conveners argue, that a nation’s fossils are most secure, and most valuable, when the people who live among them are empowered to understand, protect and celebrate them.

Subject of Research: Recognition of Mongolian palaeontologist Dr Bolortsetseg Minjin for fossil protection and repatriation, and public communication of palaeoscience at the 7th International Palaeontology Congress

Article Title: IPC7 keynote speaker receives national honor for her work to protect Mongolia’s fossils

Article References: IPC7 keynote speaker receives national honor for her work to protect Mongolia’s fossils. (n.d.). Original publication

Image Credits: AI Generated

DOI: Not provided

Keywords: Bolortsetseg Minjin, Mongolia, palaeontology, fossil repatriation, Tarbosaurus bataar, science communication, IPC7, Communicating Palaeosciences Symposium, dinosaur education, cultural heritage, Cape Town, decolonising palaeontology