Zwannda considers herself as a goal-orientated person, originally from Venda (Thohoyandou) in Limpopo Province. She was awarded BSc in Botany & Zoology and Honours in Zoology at the University of Venda, and pursued a Master’s degree in Zoology at the same University.

Growing up, she was very curious on how things interact as an ecosystem. Her love of nature and biodiversity continued during frequent field excursions in her third year Botany, Biodiversity and Conservation modules, which led her interest in pursuing Ecology studies.

For her Honours mini-dissertation, she investigated effect of drought and grazing on ants’ abundance, diversity, and distribution. Her MSc aimed to provide an understanding of the spatial structuring and role of domestication in the development of sustainable harvest techniques of Mopane worms.

In-between her postgraduate degrees, she took an internship with NRF/SANBI in the Western Cape where she gained more knowledge in this field.

Switching disciplines

During her academic journey Zwannda had the challenge of switching disciplines from Ecology to Genetics. She had to learn a variety of methods and techniques within a short period on time. “It can be tricky to get up to speed,” she recalls.

Determination, dedication, a positive attitude towards the challenge, and support I received from my laboratory mates and supervisor were things that helped me become what I am today,” she says.

Zwannda’s greatest achievement is conquering her fears.

“I always was afraid of failure and taking risks. When you are afraid, you tend to stay in one place. You start believing you can’t make progress at all, or you are incapable of it. But I have realized that it’s not about being perfect every step of the way but getting comfortable with what you don’t know.”

Career ambitions

The world human population is increasing daily.

An increase in the human population decreases available arable land and resources. With the decrease in natural resources and land for other feeding activities practiced by people; feeding the current population and the 9 billion people expected on planet earth in 2050 will take extraordinary steps and innovative advances in technology.

Zwannda would love to be part of a group of people who innovates as much technology as possible to contribute to food security in South Africa. This includes the use of non-timber forest products as an alternative source of food.

For example, the (serious) consideration of edible insects around the world as an alternative feed is one step towards food security. This includes mini livestock farming programs to ensure the availability of edible insects throughout the year.

What is Zwannda’s PhD project about?

Globally, the use of edible insects has drawn attention, as they represent an alternative source of protein for animal and human nutrition. In South Africa, wild edible insects are more prevalent and consumed in the warmer provinces of Limpopo, KwaZulu-Natal, Mpumalanga, Gauteng, and North West. Over 70 species across five orders (Coleoptera, Hemiptera, Hymenoptera, Lepidoptera and Orthoptera) were documented to be utilized in South Africa.

Despite the cultural, nutritional, and economical importance of edible insects in South Africa, genetic data on these species is still extremely scarce. Based on the available data on BOLD system v3 (accessed in March 2019), less than 40% DNA barcode data of edible insect species were recorded for South Africa. This research is compiling a comprehensive catalogue of edible insects in South Africa comprising DNA barcodes for 400 newly collected specimens across 40 species (five orders), images, and voucher specimens for future reference.

The order Lepidoptera, which includes butterflies and moths is one of the most widespread and well-known insect groups. In the South African context, the family Saturniidae (Lepidoptera) is the taxonomic group of highest economic relevance because it includes a significant number of silk-producing and edible species. Despite their significance, African Saturniidae have been poorly described, and genetic data that could assist in understanding patterns of genetic diversity and phylogeography have not been generated, except for a recent study (Langley et al, 2020).

Currently, the classification of African representatives of the family Saturniidae is largely unsatisfactory. As a result, most of complete or near-complete Saturniidae mitochondrial genomes available on GenBank are native to Asia, including some important silk producing species. As of 2020, two African Saturniidae species (the most well-known Gonimbrasia belina and Gynanisa maja) were included on the phylogeny of Saturniidae as first African representatives. This research will update the phylogeny of the family Saturniidae by sequencing and annotating the complete mitochondrial genomes of 12 African Saturniidae from five tribes to include edible species on the Saturniidae phylogeny.

Gonimbrasia belina (mopane worm) is a particularly important Saturniidae moth in Southern Africa. The harvesting and trade of mopane worms offers a livelihood benefits amongst poor communities and provides many families with significant income to purchase clothing, utensils, and support schooling of children. Most surveys provide evidence of decreasing numbers possibly due to overharvesting and other anthropogenic pressures and express a preoccupation about the sustainability of mopane worm populations in Southern Africa that spans for at least three decades.

Despite the importance mentioned above, the knowledge gap concerning the genetic characterization of this particular species is wide and urgent research is needed, as the species is polyphagous (i.e. able to feed on various kinds of food) and has potential to be farmed under human control with large benefits as compared to harvesting from the wild. This research will assess the genetic diversity and phylogeographic structure of Gonimbrasia belina (mopane worm), the most important edible insect in South Africa.

Institution: Stellenbosch University

Project Title: Edible insects of South Africa

Supervisor: Dr Barbara van Asch