Discussion
The current study aimed to combine visual surveys, literature reviews,
DNA barcoding and interviews of traditional health practitioners in
documenting and updating the knowledge of herptile use in South Africa’s
urban traditional medicine markets. This study further provided insights
into Indigenous tissue preservation methods and the willingness of some
traditional health practitioners to collaborate in conservation
initiatives aimed at traditional medicine markets.
DNA barcoding Indigenous medicine
specimens
Although Indigenous tissue preservation methods can preserve DNA for
molecular identification, storage of those specimens increases risk of
DNA contamination as they are openly displayed, and multiple species are
stored together in one container at ambient temperatures. Furthermore,
there is a risk of DNA degradation from daily temperature and humidity
fluctuations (Asari et al., 2018), as a result of those storage methods.
Spectrophotometry used to measure the absorbance of DNA samples
extracted from herptile specimens gave indications of the purity of the
extracted DNA in comparison with other coextracted products (DNA versus
other molecules), but not in terms of exogenous DNA contamination
(endogenous DNA versus DNA contamination). These absorbance measurements
were sometimes inconclusive about suitability of extracted DNA samples
for downstream applications. Some extractions that were expected to be
unsuitable for downstream applications due to their negative or outlier
absorbance ratios were amplified, and DNA sequences were obtained from
them. Additionally, some extractions with absorbance ratios close to
that of pure nucleic acid (1.8) were expected to be suitable for
downstream applications but they failed in subsequent reactions.
Since the DNA sequences from 26 of 81 specimens could not be identified
to species level, a continuation of this research could be to start with
obtaining species level identifications by barcoding the 12S, 16S, ND1,
ND2, ND4 or cytochrome b genes which have previously been used in
molecular identification of reptiles (Vences et al. 2012). It is also
possible that some of this study’s COI sequences could not be identified
due to absence of reference sequences on the BOLD and NCBI GenBank
databases. Of the 418 reptile species known to be distributed in South
Africa (Uetz et al., 2022) only 86 had COI reference sequences on the
NCBI GenBank and/or BOLD databases at the time of drafting this text (in
June 2022). The results further showed that from the 34 herptile species
recorded in published literature as being offered in the South African
urban traditional medicine circuit, eight did not have COI reference
sequences on either NCBI GenBank or BOLD databases.
DNA barcoding compared to morphology-based
identification
This study’s DNA barcoding confirmed 12 species and one genus of
reptiles from the 33 reptile species reported in published literature
which relied on morphology-based identification. The published
literature also reported one anuran species from traditional medicine
markets whereas no anurans were found during the survey and sampling
phase of this study. Philothamnus semivariegatus (Smith, 1840)
was identified in this study using DNA barcoding (Table 2), and Whiting
et al., (2011) previously recorded a genus level identification
(Philothamnus sp.) of a morphologically similar species.
Inconsistency between molecular identifications and those based on
morphology shows a need for additional barcoding studies of Indigenous
medicine specimens (Veldman et al., 2020). The hitherto estimated
species richness of traditional medicine markets is likely
underestimated due to the state of preservation of some specimens making
it difficult to obtain morphology-based identification up to species
rank
(Whiting
et al., 2011).
The mislabelling of animal tissue used for traditional cultural purposes
shown in this study (Table 3), has also been recorded in other studies
(Gombeer et al., 2021). Mislabelling could be intentional when
practitioners lie to meet customer expectations (Bitanyi et al., 2012).
It is also possible that tissue is deliberately mislabelled so the
practitioners can charge higher prices for them, but this was not the
case in this study as the mislabelled species were sold at the same
price as the correctly labelled species. Substitution of tissue in
Indigenous remedies is said to pose human health risks when toxic plants
are the substitute (Ouarghidi et al., 2012). No acute health issues have
been associated with ingestion of herptile tissue (Ngwenya, 2001; Du
Preez & Cook, 2004; Anthony & Bellinger, 2007). There is however
zoonoses risk associated with ingestion of herptile tissue and it is
worth investigating it for increased understanding of human health
effects of using animals in traditional medicine. Some of the possible
zoonotic infections include Salmonella spp. associated with
eating Crocodylus spp. meat and a chance of zoonotic parasitic
disease caused by Gnathostoma spp. nematodes in the undercooked
flesh of frogs and reptiles (Magnino et al., 2009). Furthermore, people
can be accidental hosts of some herptile parasites (Pantchev & Tappe,
2011), and herptiles are reservoirs of zoonotic parasites which may be
considered a public health concern (Mendoza-Roldan et al., 2020)
Conservation issues
South Africa’s urban traditional medicine markets rely more on reptile
species than anuran amphibian species (34 reptile species vs 1 anuran
species were jointly recorded by this and other studies). This trend of
greater dependence on reptiles than amphibians for Indigenous remedies
is global (Alves et al., 2013). The underestimation of species richness
at some of South Africa’s urban traditional medicine markets highlighted
by Whiting et al. (2011) makes it difficult to estimate the proportion
of herptile species that are considered to have traditional medicine
value and the underestimation of endangered species in particular could
lead to the traditional medicine markets’ conservation impacts being
misevaluated. It has previously been difficult to estimate the number of
individuals per species harvested for traditional medicine markets and
their impact on wildlife populations as traditional health practitioners
were reluctant to talk about their practices (Whiting et al., 2011).
There is hope for lessening this reluctance as practitioners that
participated in this study expressed willingness to collaborate with
researchers or conservation practitioners. With such collaboration the
species at traditional medicine markets can be comprehensively
documented and identified using molecular and morphology-based
identifications.
A collaborative approach to managing conservation issues arising from
traditional medicine markets would not only be just, but it is also
legally required. South Africa’s overarching environmental management
legislation is supportive of collaborative conservation planning as it
states that decisions relating to the natural environment must account
for the interest, needs, and values of interested parties and recognise
all forms of knowledge including Indigenous knowledge (Republic of South
Africa, 1998). Collaboration will of course require additional research
resources as efforts to find synergies between Indigenous cultures and
modern practices will require extra field days and additional ethics
approvals to protect Indigenous knowledge and its custodians from
exploitation. Within the context of South African environmental
legislation, Indigenous medicinal uses of wildlife (as a form of
Indigenous knowledge) should not be dismissed by conservation
practitioners. This environmental legislation further states that
management of the environment should equitably provide for people’s
needs and their cultural interests (Republic of South Africa, 1998).
Functional collaborations with traditional health practitioners have in
the past been demonstrated by modern health professionals both in South
Africa (Nkhwashu et al., 2021) and other parts of the African continent
(Kayombo et al., 2007) despite disagreement between the two parties,
thus providing hope that collaborations with conservation practitioners
are achievable. With collaboration the traditional health practitioners
can be encouraged to openly substitute endangered species with abundant
species of lower conservation priority thus limiting negative impacts of
Indigenous remedies. The manner in which practitioners sell animals for
traditional remedies can be considered to limit negative conservation
impacts (albeit unwittingly); pieces of animal tissue are sold, rather
than the entire carcass, thus allowing an individual animal to be used
by multiple people.
Traditional health practitioners would make suitable conservation
ambassadors due to the respect they have from people that follow
Indigenous cultural practices (Simelane & Kerley, 1998), and these
practitioners’ choices influence which species are collected for
traditional medicine markets through their hunts or outsourcing to
dedicated hunters. Another prospect for lessening conservation pressure
of traditional medicine markets, but not necessarily their accumulation
of endangered species, is that traditional health practitioners are
willing to take animals that died due to accidental or natural causes
(Whiting et al., 2011). There is perhaps opportunity for collaboration
between traditional health practitioners with initiatives that monitor
and collect roadkill on busy roads to lessen the hunting pressure on
species used in Indigenous remedies.
Studies of this nature that focus on the urban areas of developing
countries can contribute to increased understanding of urban
sustainability in such countries and can also contribute to policymaking
when such research is published in high visibility journals (Nagendra et
al., 2018). The study represents the first attempt in South Africa to
comprehensively document herptiles in urban traditional medicine markets
and combine DNA barcoding with morphology-based identifications and folk
taxonomy to identify herptile species at those markets. This study
transcends disciplines by combining Indigenous knowledge with DNA
barcoding and social science methodology for outcomes that can be used
for socially inclusive conservation planning. The wide applicability of
the mixed-methods approach employed here is demonstrated by Gombeer et
al. (2021) using site visits, DNA-based identification, and focus group
discussions to identify bushmeat that was smuggled to Belgium from West
African countries and highlight prevalence of Indigenous cultural
practices in the urban centre of a developed country. Incorporating
molecular identification in the introduction of collaborative monitoring
of traditional medicine markets is likely to improve understanding of
their species richness and prevent over-exploitation of herptile species
while being considerate of Indigenous practices that make use of
animals. A collaborative and mixed methods approach is also necessary
because in its absence the use of herptiles (and other animals) has
continued unmonitored while Indigenous practices and their custodians
have continually been excluded from conservation planning.