Dynamics of pastoral traditional ecological knowledge: a global state-of-the-art review

Traditional ecological knowledge enables pastoralists to cope with social-ecological changes, thereby increasing the sustainability of their practices and fostering social-ecological resilience. Yet, there is a significant knowledge gap concerning the extent to which pastoral traditional ecological knowledge has changed over time at the global level. We aim to fill this gap through a systematic literature review of 288 scientific studies on pastoral traditional ecological knowledge. We reviewed 152 papers in detail (selected randomly from the 288) for their content, and focused specifically on 61 papers that explicitly mentioned one of the four types of knowledge transition (i.e., retention, erosion, adaptation, or hybridization). Studies on pastoral traditional knowledge represent less than 3% of all the scholarly literature on traditional ecological knowledge. Geographical distribution of the 288 case studies was largely biased. Knowledge domains of pastoral knowledge such as herd and livestock management, forage and medicinal plants, and landscape and wildlife were relatively equally covered; however, climate-related knowledge was less often studied. Of the 63 papers that explicitly mentioned transition of pastoral traditional ecological knowledge, 52 reported erosion, and only 11 studies documented explicitly knowledge retention, adaptation, or hybridization of traditional knowledge. Thus, adaptation and hybridization was understudied, although some case studies showed that adaptation and hybridization of knowledge can efficiently help pastoralists navigate among social-ecological changes. Based on the review, we found 13 drivers which were mentioned as the main reasons for knowledge transition among which social-cultural changes, formal schooling, abandonment of pastoral activities, and transition to a market economy were most often reported. We conclude that future research should focus more on the diverse dynamics of pastoral traditional knowledge, be more careful in distinguishing the four knowledge transition types, and analyze how changes in knowledge impact change in pastoral practices and lifestyles. Understanding these phenomena could help pastoralists’ adaptations and support their stewardship of their rangeland ecosystems and biocultural diversity.


INTRODUCTION
Since the 1992 Rio Earth Summit, the importance of traditional ecological knowledge (TEK) in the conservation of biological and cultural diversity has been increasingly acknowledged by both the scientific community and policy-makers around the globe (Maxted et al. 2002). TEK plays a vital role in the livelihoods of rural communities and the sustainable management and use of natural resources by Indigenous peoples and local communities (Olsson and Folke 2001). Opinions about TEK, previously rife with negative characteristics such as being static and archaic, are now appreciating the dynamic nature of this knowledge and related practices. An increasing number of studies involving traditional farmers (Cristancho andVining 2009, McCarter andGavin 2014) and hunter-gatherers (Fernández-Llamazares et al. 2015, Gallois et al. 2015 have shown nonadaptive changes in TEK, mostly loss of TEK due to changes in intergenerational transmission mechanisms or other drivers (Srithi et al. 2009, Reyes-García et al. 2013. But despite a myriad of cultural pressures, many aspects of TEK systems are resilient. There is mounting evidence that TEK is adaptive to changes in the environment and is fluid with social-economic and cultural changes (Berkes et al. 2000, McCarter et al. 2014). Thus, not all changes in Indigenous and local knowledge systems should be labeled as knowledge loss as long as loss of knowledge is not accidental and does not impair the efficient functioning of the practice. Thus, changes should often be evaluated from an adaptation perspective (Jandreau and Berkes 2016). https://www.ecologyandsociety.org/vol27/iss1/art14/ communities seems to have received less attention than that of other groups, while the relevance of pastoralism globally remains undeniable (Johnsen et al. 2019). These knowledge gaps and the urgency of their study are highlighted through the planned 2026 International Year of Rangelands and Pastoralists declared by the United Nations, which has announced the intention to address Indigenous knowledge and culture of pastoral communities (Kelly 2020). Globally, pastoralists are reported to number from 250 to 500 million people (McGahey et al. 2014, Johnsen et al. 2019. Relying on their TEK, pastoralists across the globe have been able to produce livestock in often unpredictable and highly variable conditions of rangelands that range from deserts to steppes, tundras, savannah, and mountainous areas (Stolton et al. 2019). This lifestyle is the result of close and intimate interrelations between people and nature, which lead to the formation of rich and complex bodies of knowledge, practice, and beliefs , Fernández-Giménez 2000, Molnár 2017). Many pastoralists are encountering rapid and fundamental changes in climate, the frequency of droughts and floods, the market economy, forage and fodder availability, social-cultural systems, and land use rights, but importantly, also regulations and policies that limit some of their practices and affect processes needed for the generation and transmission of TEK (Galvin 2009, Reid et al. 2014, Herrero et al. 2016, Belayneh and Tessema 2017. Such changes are leading to notable transitions in pastoral TEK (Bussmann et al. 2018, Hedges et al. 2020).
Pastoral TEK is not only essential for its role in improving the functionality of rangeland ecosystems (Shen et al. 2019), biological diversity (e.g., productive local livestock breeds that are tolerant of unique environments) (Hoffmann et al. 2014), sustainable management (conservation values of territories and their flora and fauna) (Fynn et al. 2016), and social and cultural preservation (e.g., 22 intangible cultural heritage items on the UNESCO list) (Stolton et al. 2019), but also for enhancing the social-ecological resilience and adaptability of pastoral communities to the challenges caused by diverse global changes , Yacoub 2018. Pastoral TEK contains several domains such as herd management; forage, fodder, and medicinal values of plant species; weather forecasting; and management of spatiotemporal heterogeneity of natural resources. Hence, lack of knowledge transmission or any negative change in different knowledge domains of pastoral TEK can cause irreversible effects on pastoral systems and their sustainability (Jandreau and Berkes 2016). Pastoral knowledge and practices are context-based and locally grounded, evolving and adapting to specific social-ecological conditions. However, this knowledge is regionally manifested and globally relevant (Brondízio et al. 2021), and has elements in common across pastoral systems. A recently published Scientists' Warning to Humanity on threats to Indigenous and local knowledge systems raises the importance of globally assessing the status of and trends in TEK systems (Fernández-Llamazares et al. 2021), and highlights how common global patterns are similarly affecting locally adapted knowledge systems. Such assessments are largely missing in the context of pastoralism, and few efforts have cut across disciplinary topics or regions (see Manzano-Baena et al. 2021 for a discussion).
We aim to synthesize the state of the art of knowledge on pastoral TEK and its dynamics, cutting across disciplinary topics and regions. To do so, we conducted a systematic review of scientific papers that dealt specifically with changes in pastoral TEK. To understand whether reported changes are viewed as adaptive, we focused on four types of TEK transition: retention, erosion, adaptation, and hybridization (see Theoretical Background for definitions). We addressed whether research is homogenous across knowledge domains (e.g., general ecological knowledge, knowledge on livestock management), and across main pastoral mobility types (sedentarism, transhumance, and nomadism) in search of regional or global patterns that could indicate drivers of change and threats to adaptive TEK dynamics.

THEORETICAL BACKGROUND
Prior to providing a definition for TEK, we defined Indigenous peoples and local communities as typically, ethnic groups who are descended from and identify with the original inhabitants of a given region who are dependent on nature for providing necessities of their livelihood in a sustainable way (IPBES 2019). TEK systems are cumulative bodies of knowledge, practices, and beliefs of Indigenous peoples and local communities that evolve by adaptive processes and are handed down through generations by cultural transmission (Berkes et al. 2000). We note that this definition is largely consistent with the one of "Indigenous and local knowledge systems" used by IPBES (2021), which defines these systems as "social and ecological knowledge, practices and beliefs pertaining to the relationship of living beings, including people, with one another and with their environment".
While pastoralism has multiple definitions and understandings, we focus on pastoral livelihoods that aim at raising domesticated and semidomesticated livestock within nature. This entails the movement of people and herds across landscapes, making use of natural vegetation and crop by-products. Pastoralism is about animals walking to their feed instead of having it grown, cut, and brought to them. In pastoral systems, animals are grazed and foraged in an extensive system instead of being stall-fed in an intensive system (Köhler-Rollefson 2020).
Four knowledge transitions were considered in this study. Retention is defined as the continuity and persistence of TEK without significant change in its quality and quantity; erosion is the decline or loss of TEK; adaptation is the transformation of TEK to adjust to changes in the environment and conditions; and hybridization is the integration of TEK into another knowledge system (Thomas and Twyman 2004, Zent 2013, Fernández-Llamazares et al. 2021. While much research has focused largely on loss of pastoral knowledge (e.g., Hedges et al. 2020), many pastoral knowledge systems have also demonstrated resilience to social-ecological changes due to their inherently adaptive and dynamic nature (Galvin 2009). The adaptability and resilience of pastoral knowledge systems is evident in many ecosystems around the world, which bear evidence of pastoral practices over millennia (Jandreau andBerkes 2016, Ellis et al. 2021).
We acknowledge that changes in TEK ramify through complex pathways, and that causality flows in multiple directions and is often circular. TEK changes usually modify the ecosystems that are shaped by such systems, and then the opportunities for practicing TEK (as a local expression of culture) are constrained We also note from the outset that none of the authors are members of pastoralist communities, and that our review reflects a situated and partial interpretation of pastoral knowledge dynamics. However, we draw on several decades of in-depth field-based ethnographic experience among pastoral societies on several continents. While we see value in bringing into focus the global extent of pastoral TEK, we understand that a global review such as this one has the potential to obscure the very place-based nature of TEK and the rich diversity of pastoral cultures and knowledge systems (see Ford et al. 2016). By presenting real-world examples from all inhabited continents, we aim to emphasize the different place-and culture-specific ways in which pastoralists navigate changes in their knowledge systems

METHODS
The first step of the review process was to undertake a systematic literature search for peer-reviewed scientific articles about pastoral TEK using Web of Science. This search was carried out on 28 November 2019 and was guided by keywords that covered various phrases for both TEK and pastoralists which were selected and applied to find all available papers published in English regarding pastoral TEK. We used the following Boolean phrase to search not only the titles, but also the whole body of the papers: TS = (("aborigin* knowledge" OR "traditional knowledge" OR "traditional local knowledge" OR "ecological knowledge" OR "traditional environmental knowledge" OR "Indigenous knowledge" OR "local knowledge" OR "folk knowledge") AND (pastoral* OR flock* OR herd* OR shepherd*)). This led to the identification of 382 papers, from which 372 papers were traceable (Appendix 2). In the next step of the study, the title, Abstract, and Materials and Methods sections of all 372 papers were screened to omit papers unrelated to pastoral TEK. Thereby, 84 papers were eliminated in this phase. For instance, using keywords "flock" or "herd" with TEK-related keywords such as "local knowledge" led to some fishing-related TEK papers, which were disregarded at this phase. For the remaining 288 papers, we reviewed the types of TEK transition reported (especially adaptation and hybridization), and the countries where each study was conducted (Table A1.1).
In the third step, we proceeded to subsample papers for a more detailed, quantitative review. To do so, the 288 papers were sequentially numbered (1 to 288), and a random number generator was applied (using the "= RAND ()" function in Microsoft Excel 2019) to select the first approximately 102 papers, with a further addition of 50 more papers to assess the robustness of findings (Table A1.2). For these papers, we recorded the title, journal, DOI, and first author's name, and eight variables of interest: year of the study, the country where the study was conducted, pastoral system type, studied knowledge domain, mention of TEK transition, type of knowledge transition, robustness of reported transition, and drivers of knowledge transition (Table 1). Classification of papers as reporting knowledge transitions (and transition type) was done based on text mentions (in the Results and Discussion), not on our own interpretation of the paper's data. To check the robustness of reported transition type, three different states of evidence-based report of transition, anecdotal report of transition, and nonevidence-based report of transition were considered. Further explanation is provided in Table 1. Since the relative frequency of the investigated variables was not significantly different between the primary studies (102) and the final set (152) (p > 0.05; Table  A1.3), the result was viewed as robust enough, so the remaining (136) papers were not inspected for this detailed quantitative analysis. In terms of the geographical distribution of research on pastoral TEK (Fig. 2), most studies were conducted in Africa (50%), followed by Asia (30%), and Europe (14%). Studies on pastoral TEK were scant in Oceania (3%), South America (2%), and North America (1%). Overall, pastoral communities in 62 countries were studied, with Ethiopia (33 studies), Kenya (31), India (19), and China (18) being the most prominent ones.  Hanazaki et al. (2013) also found that Ethiopia, India, and China were hotspots for TEK-related research. In the case of scientific studies on rangelands and pastoralism (as a whole), China, Mongolia, Australia, Kenya, and Ethiopia had the highest share of studies (Johnsen et al. 2019).
Our results also showed that 20 countries were represented by only a single study. Noting that pastoral identities may vary within countries, with several Indigenous groups or ethnicities recognized in many countries, single studies are certainly not representative enough. For example, of the 42 recognized ethnic groups in Kenya (many of which practice some form of pastoralism; see, for example, LPP [2021]), only nine groups were included in more than one study. In another example, yak herding is practiced among at least 31 ethnic groups in the Asian highlands, yet only a few studies of some ethnic groups were available. In Buthan and Tajikistan, for instance, where together five ethnic groups are active in yak herding, only two general papers were found, and neither of them focused specifically on yak herding (Kassam 2009, Wu et al. 2014. We found that some countries with large pastoral populations (e.g., Kazakhstan, Yemen, Somalia, and Uzbekistan) were not represented in the literature. This also extends to countries such as Central African Republic, Uruguay, or Eswatini, where more than 50% of the land is categorized as rangelands (Johnsen et al. 2019). This could be related to language barriers in science; much research written in French, Spanish, and Russian was not included in this study. We acknowledge that overlooking such literature can bias outcomes of evidence synthesis and lead to only a partial understanding of pastoralism at the global level.
Knowledge domains and pastoral mobility types are unevenly studied Similar attention has been paid to five major TEK domains related to herd and livestock management knowledge, forage and medicinal plant knowledge, and knowledge of landscape and wildlife (i.e., 73, 75, 70 studies, respectively). Interestingly, despite growing research interest in pastoral vulnerability to climate change, pastoral TEK about climate has received relatively scant scholarly attention, with only 15 studies on climate-related knowledge domains. This knowledge is vital to vulnerability and adaptation assessment, and confronts policymakers with many research gaps (Ahearn et al. 2019). Pastoral TEK regarding climate and weather forecasting has enabled pastoralists to adjust their seasonal movement and cope with changes in precipitation and temperature, which dramatically affect the variability and availability of forage, fodder, and water sources (Nkuba et al. 2019). Also, the integration of climaterelated TEK, which is based on a variety of biological, cultural, and astrological indicators, with scientific forecasts could improve the accuracy, uptake, and application of weather forecasting by locals , Radeny et al. 2019).
The papers reviewed often lacked information regarding the type of pastoral way of life and/or mobility systems. Of the 58% of papers that did provide information on mobility types, most focused on nomadic (56%); fewer focused on transhumant (32%) and sedentary (25%) systems. When considering domains of knowledge and pastoralism types, it was less clear whether representativeness was even. It seems that ethnographic studies that addressed TEK tended to focus on groups that live more traditionally and have been less exposed to globalization; thus, this could reflect the greater attention paid to nomadic systems.

Transition in pastoral traditional ecological knowledge: erosion versus retention, adaptation, and hybridization
Transitions in pastoral TEK were addressed in 41% of the 152 papers reviewed in detail (Fig. 3A). Each of the four types of knowledge transition (i.e., retention, erosion, hybridization, and adaptation) was mentioned in at least one paper; erosion of knowledge was the transition type most often reported (83%). Retention, hybridization, and adaptation were each mentioned in 6% or less of the papers (Fig. 3B). Of all the transitions reported, 35% were based on robust empirical evidence, 17% were anecdotal, and 48% relied on weak empirical footing, as no traceable form of evidence was provided in the paper. In general, the interest in studying transitions in pastoral TEK is growing in a similar way as the number of studies in pastoral TEK (Fig. 3). TEK erosion was commonplace globally but was most often reported in Asia and East Africa (Fig. 4). In Europe, Asia, and Africa, 55%, 53%, and 31% of the total number of studies, respectively, reported some form of TEK transition. Reported transition showed Ethiopia, India, China, Kenya, Egypt, and Spain with more reports of erosion. Although comparing the status of TEK transition among countries is difficult because research effort is far from homogenous across countries, it is important to highlight that TEK erosion is reported in most of the studied countries, even in biologically and culturally diverse regions.
Knowledge erosion was reported in similar frequency for all five major knowledge domains. However, we found a greater relative frequency for the domains Herd/Livestock (42%) and Forage/ Medicine (44%) (Fig. 5). All domains reported at least 25% for erosion of pastoral TEK. Without considering retention of TEK as a "change", the highest frequency for any type of TEK transition was reported for the Forage/Medicine (48%) and Social-cultural (47%) domains. Hybridization and adaptation were reported for only three knowledge domains each. The small number of available studies made it difficult to find robust global patterns.
From all the studies in which the type of pastoral system was mentioned, nomadic, transhumant, and sedentary systems (45% [24 papers], 33% [18 papers], and 22% [12 papers], respectively) were mentioned to be affected by some form of TEK transition (Fig. 5). In all three pastoral system types, erosion was the most often reported transition, and in most cases, retention, adaptation, and hybridization was found only in a few cases. Further research is needed to obtain a better and more representative understanding of the differences in knowledge transitions across different pastoral mobility systems.
Regardless of the lifestyle that pastoralists have (nomadism, transhumance, or sedentarism), loss of unnecessary knowledge and accumulation of new knowledge occurs with time and new practices. In other words, if a community has a sedentary lifestyle, it does not mean that they have lower TEK compared to nomads (Nedelcheva et al. 2017). However, shifting from one lifestyle to another could affect the knowledge that pastoralists are "carrying" with themselves , Bussmann et al. 2018. The slightly greater erosion of knowledge reported for transhumant and sedentary systems could suggest that some of these communities are increasingly shifting to sedentary lifestyles. Therefore, due to the shift, and at least regarding some knowledge domains that are less applicable in the new lifestyle, the volume of pastoral TEK may decline (Dong et al. 2011, Bussmann et al. 2018).
The relatively greater number of papers that reported pastoral TEK erosion may be alarming for local, national, and international organizations that are aiming to promote sustainable use of rangelands and biocultural conservation of pastoral social-ecological landscapes. Aswani et al. (2018) and Hanazaki et al. (2013) reported the same result when conducting reviews on TEK transition among other communities such as farmers, hunter-gatherers, and fishers, and found that 77% and 57% of the papers reviewed reported TEK erosion, respectively.
As pastoral communities are being impacted by changes in climate, culture, technology, social-economic conditions, and policies at various scales (Reid et al. 2014), so too are their TEK systems. On one hand, erosion of pastoral TEK could be the consequence of the change; on the other hand, it could be the very driver of the change. For example, recent changes in plant diversity in Eastern Africa have caused the extinction of some plant species that were used in weather forecasting and prediction by Borana pastoralists in southern Ethiopia and northern Kenya. This extinction has led to the erosion of knowledge about these plant species. Losing the knowledge of weather forecasting has affected pastoral migration and movement abilities, which consequently debilitates the Borana's resilience to climate change (Radeny et al. 2019).
Due to the low number of studies and the research gaps we identified, knowledge transition patterns found in this review cannot be considered indicative of what is happening to pastoral TEK globally. Importantly, not a single study addressed all types of knowledge domains or compared all types of pastoral mobility systems regarding knowledge transitions. Only one knowledge Ecology and Society 27(1): 14 https://www.ecologyandsociety.org/vol27/iss1/art14/ domain was covered in 49% of the studies, and only two were addressed in 37% of the studies. Also, regarding the subdomains (Table 1), 91% of studies focused on less than three subdomains, while approximately 2% of studies covered six subdomains: Oteros-Rozas et al. (2013), , and Jandreau and Berkes (2016).
Another research gap in pastoral TEK studies is that although different transitional types have been reported for pastoral TEK, most of the studies have labeled TEK transition as erosion. As it was also emphasized by Tian (2017), TEK transition is evaluated primarily linearly as gain or loss; however, adaptation and hybridization of TEK are also possible-and highly relevantchanges. Researchers have often assessed the transition of pastoral TEK by comparing the volume of knowledge between or within generations (Oteros-Rozas et al. , Salpeteur et al. 2015 and have referred to the lower volume of knowledge of the younger generation as erosion. However, compared to the older generation, the new generation could be less knowledgeable, for instance, about plant species that used to be dominant in the region, while having gained more knowledge about a newly arrived invasive species ). In another case, changes in herd composition from cattle to sheep that are driven by market demands have resulted in the new generation having more knowledge about sheep but fading knowledge regarding cattle, which is no longer applicable based on the new circumstances (Adriansen 2008). We argue that erosion of TEK concerning specific subdomains should not automatically imply the overall downward trend in communities' TEK. In fact, this change may originate from adaptive strategies and/or hybridization of knowledge due to exposure to other knowledge systems.

Examples of adaptation, hybridization, and retention of pastoral traditional ecological knowledge
Adaptation, although rarely studied explicitly (only four studies, 6% of the sample), has been reported both in nomadic and transhumant systems (Fig. 5), and across several knowledge domains (i.e., Social-cultural, Forage/Medicine, and Landscape/ Wildlife). Yet, no adaptation has been reported for Herd/ Livestock and Climate knowledge domains. Knowledge adaptation among pastoralist societies is largely underrepresented in the scholarly literature, particularly so if we consider that pastoralism is a resilient and highly adaptive livelihood and the most widespread land use on Earth (Reid et al. 2014). Adaptive changes in pastoral practices (see, for example, ) deserve much more scholarly and policy attention than they have received to date. Similarly, hybridization has been poorly studied, but we found examples of hybridization across pastoral mobility types and some knowledge domains, though with no clear patterns. Knowledge retention was also mentioned in three studies. In one study, the new generation was found to carry greater knowledge regarding one domain compared to the elder generation (see Naah and Guuroh [2017] for more information). To illustrate differences between adaptation, hybridization, and retention, Table 2 presents some case studies.

Major drivers of traditional ecological knowledge transition: pastoral knowledge is threatened
Causality flows in multiple directions and is iterative: loss of TEK changes the ecosystems that were shaped by it, and the Ecology and Society 27(1): 14 https://www.ecologyandsociety.org/vol27/iss1/art14/ Adaptation: Pastoralists cope with changes in environment and social-economic conditions through adaptive strategies. Implementation of new practices is based on adaptive knowledge that makes the adjustment of pastoral systems to changes effective. Kenya: Due to diet changes among Maasai pastoralists, shifting from milk and meat centered to more agricultural crops, girls' activities and TEK regarding firewood collection have expanded and adapted by putting more time into wood collection and involvement of younger children. Also, with developing formal schooling in the region, firewood collection has been adjusted to a shorter period prior to school time.
Tian (2017) Russia: After the collapse of the Soviet Union, Siberian Evenki people who were living in the Arctic forest tundra region of northwestern Yakutia changed their basic subsistence from reindeer herding to a combination of herding and hunting due to environmental change, political regime change, and economic development.
Takakura (2012) Bolivia: As trends of diminishing water availability are recorded across the Andes, mountain peatlands (bofedales), which are the main pastureland for camelid pastoralists, are becoming more degraded and drier. Consequently, Andean pastoralists have adopted collective irrigation practices to rehabilitate these pastures which were used in the past.
Yager et al.
Benin: Fulbe pastoralists' perception and TEK regarding animal genetic breeds have adapted to new environmental and social-political regulations. For instance, with encroachment of farmlands, which is resulting in the loss of grazing areas and watering points, cattle herders' preferences for breeds are changing from high milk and meat production to breeds that are tolerant to hunger and long walks is search for forage. Also, scarce grazing land had made pastoralists use specific breeds that are good at escaping from agents responsible for illegal grazing.
Hybridization: Exposure to other knowledge systems and technologies leads to the development of hybrid knowledge and practices that are based on them. This exposure may contribute to changes in management but also to a change of values pastoralists follow. Hybridization-whether done voluntarily or involuntarily-is another strategy to make persistency of pastoral systems possible. China: In the past, Tibetan herders' traditional knowledge influenced by Buddhist teaching viewed yaks as sentient beings that should not be slaughtered; however, being subjected to market-driven logic, slaughtering is currently considered a necessary process. The contemporary forces have resulted in the hybrid indigenous knowledge of Tibetan pastoralists in a way that most of them do not reject one view for the other; rather, they employ both.
Gaerrang (2017) Spain: Younger Spanish shepherds in the Cantabrian Mountains are exposed to external sources of training and information, including the Internet, which has resulted in new understanding regarding scavengers and their role in other nature-based subsistence, such as nature tourism. Therefore, the population of Griffon Vultures (Gyps fulvus) has increased due to this hybridization of knowledge.

Morales-Reyes et al. (2019)
Australia: Indigenous cattle herders' practices in Oriners Station (Indigenous-owned pastoral lease east of Kowanyama) have been influenced by operational knowledge of national parks and contemporary management, which has led to hybridization of their knowledge. Currently, pastoralists compromise with other involved stakeholders such as conservationists and scientists in implementing their traditional-based practices such as horse riding. Barber et al. (2014) Uganda: As the result of being exposed to modern weather prediction techniques and information, pastoralists' knowledge in the Rwenzori region regarding predicting and forecasting weather features is currently a hybrid knowledge based both on scientific and traditional knowledge.
Retention: Knowledge transmission is constantly occurring without any gap within or between generations. Kenya: Despite the gradual shift from a nomadic to sedentary lifestyle, pastoral knowledge regarding botanical features of plant species was uniformly shared across age and gender, and source of livelihood. Stave et al. (2007) India: Children of the semi-nomadic Gujjar tribe (buffalo herders) in the high altitude of the Western Himalaya still accompany their fathers and elder generation to the higher altitude and learn about useful plant species through observation.

Rana et al. (2019)
Ghana; Burkina Faso: Free forage plant listing ability of the elder generation was the same as younger generation. In some cases, it was shown that younger generations carry greater knowledge pertaining to forage species than the elders, which showed the intrinsic flexible nature of pastoral TEK acquisition and transmission. Naah and Guuroh (2017) opportunities for practicing TEK as an expression of culture are constrained by that new ecological trajectory. As a result, the loss itself, the cause of the loss, and the consequences of the loss are often interwoven; therefore, causes of TEK transition cannot be directly associated to simple factors. Nevertheless, we identified 13 drivers that are affecting pastoral TEK transitions, which were mentioned individually or in combination in the reviewed papers (Table 3). Social-cultural changes (13 citations), formal schooling (11 citations), abandonment of pastoral activities (11 citations), and transition to a market economy (10 citations) were the most often reported causes.