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This article provides an overview of the biodiversity and evolution of African flora. Africa is home to a diverse range of ecosystems and has a rich variety of vascular plants, with over 65,000 recorded species. However, the cataloging of African plant diversity is uneven, with some regions well-documented and others barely explored. The article also explores the biogeographic history of African plants, the role of fire in shaping the flora, and the impact of climate change on plant diversity. The authors emphasize the need for conservation efforts specific to Africa, as the processes that have shaped its flora differ from those in other parts of the world. They also highlight the gaps in our understanding of African plant diversity and call for further research and data collection. [Extracted from the article]

Ecologically specialized plants are expected to be at greater risk of extinction than generalists due to climate change. Such risk is greatest in biodiversity hotspots such as the Greater Cape Floristic Region (GCFR), which accommodates both ecological specialists and generalists. Thesium L., a genus with the highest number of species in Santalaceae and the most diverse in Africa, offers an appropriate system for evaluating both the correlates of range extent and specialization and the relative extinction risks associated with both. We hypothesized that range size, ecological specialization, and consequent climatically modulated extinction risks are all phylogenetically structured, such that climate change will precipitate a disproportionate loss of phylogenetic diversity in the GCFR Thesium. Past and future species distribution ranges were predicted using MaxEnt models based on present‐day occurrences and environmental conditions. Of the 101 Thesium species modeled, 70% have had large range sizes during the Last Glacial Maximum (LGM), 50% currently have a large range size, and future conditions are predicted to allow 40% to obtain large range sizes. Between the LGM and the present, 17% of species are thought to have undergone a contraction of available range space in the present time whereas 37% are expected to expand their ranges into the future, while 51% of species will experience range contractions. Of the 65 species currently ranked as Least Concern in the South African Red List, 24% will likely shift into higher extinction risk categories. Interestingly, 8.5% of ecological specialists, although having experienced a range reduction from the LGM to the present, are predicted to persist in the face of future climate change. However, the range extent, ecological specialization, and extinction risk are phylogenetically random and therefore should have a negligible impact on the phylogenetic diversity of the GCFR Thesium. [ABSTRACT FROM AUTHOR]

As recently circumscribed, Sesamum was rendered monophyletic by including the three segregate genera Ceratotheca , Dicerocaryum and Josephinia. Here, the monophyly of Sesamum and the currently accepted infrageneric taxa was tested using expanded phylogenetic analyses. In addition, nine taxonomically useful morphological characters were optimized on the resulting phylogenetic tree to assess their evolutionary pattern. The phylogenetic analyses support the expanded circumscription of Sesamum and the monophyly of Sesamum section Sesamum relative to Sesamum sections Aptera, Ceratotheca , Chamaesesamum , Dicerocaryum , Josephinia and Sesamoptera. Most sections were retrieved as monophyletic, except Sesamum section Ceratotheca which was shown to be paraphyletic. Character reconstruction infers the ancestor of Sesamum to have had an erect growth habit, simple leaves with entire margins, ovaries with incompletely divided locules, indehiscent capsules that are oblong-quadrangular in lateral view with a beaked apex and winged seeds. Relative to the ancestral states, Sesamum has dehiscent fruits and fully divided locules as synapomorphies, with reversals to the ancestral state (indehiscence, undivided locules) in Sesamum sections Josephinia and Dicerocaryum. The absence of trichomes on mature vegetative parts and the development of lobed leaves are synapomorphies for Sesamum section Sesamopteris. Characters such as dentate and lobulate leaf margins and discoid fruit with horn-like protrusions are homoplastic in Sesamum. Dated phylogeny and ancestral range estimation suggest a southern African origin for the genus with subsequent diversification to tropical Africa, India and Australia. Sesamum has an estimated crown age of 38.1 ± 5.2 Myr with subsequent dispersal scenarios into tropical Africa, Asia and Australia during the Miocene from 24.5 Mya. Dispersal, rather than continental vicariance, is the probable explanation for the pantropical distribution of Sesamum. [ABSTRACT FROM AUTHOR]

Background and Aims It is unclear how widespread polyploidy is throughout the largest holocentric plant family – the Cyperaceae. Because of the prevalence of chromosomal fusions and fissions, which affect chromosome number but not genome size, it can be impossible to distinguish if individual plants are polyploids in holocentric lineages based on chromosome count data alone. Furthermore, it is unclear how differences in genome size and ploidy levels relate to environmental correlates within holocentric lineages, such as the Cyperaceae. Methods We focus our analyses on tribe Schoeneae, and more specifically the southern African clade of Schoenus. We examine broad-scale patterns of genome size evolution in tribe Schoeneae and focus more intensely on determining the prevalence of polyploidy across the southern African Schoenus by inferring ploidy level with the program ChromEvol, as well as interpreting chromosome number and genome size data. We further investigate whether there are relationships between genome size/ploidy level and environmental variables across the nutrient-poor and summer-arid Cape biodiversity hotspot. Key Results Our results show a large increase in genome size, but not chromosome number, within Schoenus compared to other species in tribe Schoeneae. Across Schoenus , there is a positive relationship between chromosome number and genome size, and our results suggest that polyploidy is a relatively common process throughout the southern African Schoenus. At the regional scale of the Cape, we show that polyploids are more often associated with drier locations that have more variation in precipitation between dry and wet months, but these results are sensitive to the classification of ploidy level. Conclusions Polyploidy is relatively common in the southern African Schoenus , where a positive relationship is observed between chromosome number and genome size. Thus, there may be a high incidence of polyploidy in holocentric plants, whose cell division properties differ from monocentrics. [ABSTRACT FROM AUTHOR]

Thesium muasyae, a new species of the family Santalaceae, is described and illustrated. This species has unique morphological and ecological characters, differentiating it from other closely related species of the genus, such as T. karooicum. These characters include plants forming compact shrubs to about 30 cm tall with glabrous surfaces; leaves recurved, to about 4 cm long, terete to triangular, apiculate; flowers placed in lax spikes or borne solitary; and style up to about 2.5 mm long. Ecologically, T. muasyae is endemic to the limestone fynbos in the Overberg, Bredasdorp District, South Africa. Molecular phylogenetic evidence places this species in Subgenus Frisea Section Barbata, as closest sister to T. hispidulum + T. karooicum. A preliminary conservation Red List assessment suggests that T. muasyae is Critically Endangered, based on its population size, area of occupancy and extent of occurrence. [ABSTRACT FROM AUTHOR]

Tinnea gombea, endemic to the Sudan savanna grasslands in northern Nigeria, is described and illustrated. We used integrative evidence from morphological characters, ecology and molecular phylogenetic data. The new species is morphologically and ecologically similar to T. barteri and T. aethiopica, but can be readily delimited from these taxa by unique characters including a subshrub growth habit, leaves alternate to subopposite, blades lanceolate, apically acuminate, inflorescences raceme, bearing solitary flowers in upper leaf and bract axils, lilac to purplish dusky flowers and the inflated fruits dehiscent. The distribution and habitat of T. gombea are also distinctive, being restricted to the Sudan savanna, while the two most similar species are widespread in tropical Africa. Additionally, molecular phylogenetic assessments using nrITS and chloroplast trnL-F, matK and rbcL support the placement of T. gombea as a distinct species. Tinnea gombea is here assessed as Critically Endangered due to its small population size and restriction to a small area lacking conservation prioritization. [ABSTRACT FROM AUTHOR]

Premise Methods Results Conclusions Increases in genome size in plants—often associated with larger, low‐density stomata and greater water‐use efficiency (WUE)—could affect plant ecophysiological and hydraulic function. Variation in plant genome size is often due to polyploidy, having occurred repeatedly in the austral sedge genus Schoenus in the Cape Floristic Region (CFR), while species in the other major schoenoid genus in the region, Tetraria, have smaller genomes. Comparing these genera is useful as they co‐occur at the landscape level, under broadly similar bioclimatic conditions. We hypothesized that CFR Schoenus have greater WUE, with lower maximum stomatal conductance (gwmax) imposed by larger, less‐dense stomata.We investigated relationships between genome size and stomatal parameters in a phylogenetic context, reconstructing a phylogeny of CFR‐occurring Schoeneae (Cyperaceae). Species’ stomatal and functional traits were measured from field‐collected and herbarium specimens. Carbon stable isotopes were used as an index of WUE. Genome size was derived from flow‐cytometric measurements of leafy shoots.Evolutionary regressions demonstrated that stomatal size and density covary with genome size, positively and negatively, respectively, with genome size explaining 72–75% of the variation in stomatal size. Larger‐genomed species had lower gwmax and C:N ratios, particularly in culms.We interpret differences in vegetative physiology between the genera as evidence of more‐conservative strategies in CFR Schoenus compared to the more‐acquisitive Tetraria. Because Schoenus have smaller, reduced leaves, they likely rely more on culm photosynthesis than Tetraria. Across the CFR Schoeneae, ecophysiology correlates with genome size, but confounding sources of trait variation limit inferences about causal relationships between traits. [ABSTRACT FROM AUTHOR]

Background and Aims The quartz fields of the Greater Cape Floristic Region (GCFR) are arid and island-like special habitats, hosting ~142 habitat-specialized plant species, of which 81 % are local endemics, characterized by a rapid turnover of species between and among sites. We use several phylogenetic community metrics: (1) to examine species diversity and phylogenetic structure within and among quartz fields; (2) to investigate whether quartz field specialists are evolutionarily drawn from local species pools, whereas the alternative hypothesis posits that there is no significant evolutionary connection between quartz field specialists and the local species pools; and (3) to determine whether there is an association between certain traits and the presence of species in quartz fields. Methods We sampled and developed dated phylogenies for six species-rich angiosperm families (Aizoaceae, Asteraceae, Crassulaceae, Cyperaceae, Fabaceae and Santalaceae) represented in the quartz field floras of southern Africa. Specifically, we focused on the flora of three quartz field regions in South Africa (Knersvlakte, Little Karoo and Overberg) and their surrounding species pools to address our research questions by scoring traits associated with harsh environments. Key Results We found that the Overberg and Little Karoo had the highest level of species overlap for families Aizoaceae and Fabaceae, whereas the Knersvlakte and the Overberg had the highest species overlap for families Asteraceae, Crassulaceae and Santalaceae. Although our phylogenetic community structure and trait analyses showed no clear patterns, relatively low pairwise phylogenetic distances between specialists and their local species pools for Aizoaceae suggest that quartz species could be drawn evolutionarily from their surrounding areas. We also found that families Aizoaceae and Crassulaceae in Knersvlakte and Little Karoo were phylogenetically even. Conclusions Despite their proximity to one another within the GCFR, the studied areas differ in their species pools and the phylogenetic structure of their specialists. Our work provides further justification for increased conservation focus on these unique habitats under future scenarios of global change. [ABSTRACT FROM AUTHOR]

Background and Aims The Greater Cape Floristic Region is one of the world's biodiversity hotspots and is considered poor in polyploids. To test this assumption, ploidy variation was investigated in a widespread Cape shrub, Dicerothamnus rhinocerotis (renosterbos, Asteraceae). The aim was to elucidate the cytotype distribution and population composition across the species range, and to assess differences in morphology, environmental niches and genetics. Methods Ploidy level and genome size were determined via flow cytometry and cytotype assignment was confirmed by chromosome counting. Restriction site-associated DNA sequencing (RADseq) analyses were used to infer genetic relationships. Cytotype climatic and environmental niches were compared using a range of environmental layers and a soil model, while morphological differences were examined using multivariate methods. Key Results The survey of 171 populations and 2370 individuals showed that the species comprises diploid and tetraploid cytotypes, no intermediates and only 16.8 % of mixed populations. Mean 2C values were 1.80–2.06 pg for diploids and 3.48–3.80 pg for tetraploids, with very similar monoploid genome sizes. Intra-cytotype variation showed a significant positive correlation with altitude and longitude in both cytotypes and with latitude in diploids. Although niches of both cytotypes were highly equivalent and similar, their optima and breadth were shifted due to differences mainly in isothermality and available water capacity. Morphometric analyses showed significant differences in the leaves and corolla traits, the number of florets per capitulum, and cypsela dimensions between the two cytotypes. Genetic analyses revealed four groups, three of them including both cytotypes. Conclusions Dicerothamnus rhinocerotis includes two distinct cytotypes that are genetically similar. While tetraploids arise several times independently within different genetic groups, morphological and ecological differences are evident between cytotypes. Our results open up new avenues for questions regarding the importance of ploidy in the megadiverse Cape flora, and exemplify the need for population-based studies focused on ploidy variation. [ABSTRACT FROM AUTHOR]

• 95 plants, 65% wild, were used for treatments of 45 livestock ailments. • Datura stramonium was the most often cited species. • Asteraceae had highest therapeutic values. • Males, elders, and those with no formal education enumerated higher plant numbers • The highest informant consensus was for bloating, bloody diarrhea and eye infection Livestock production is an integral part of the agricultural industry in Ethiopia. However, livestock diseases are a major hindrance especially among rural communities lacking access to conventional veterinary services. This study was conducted to explore medicinal plants and practices used to treat livestock ailments across varied agro-climatic zones in northeastern Ethiopia. Ethnoveterinary data was collected between December 2019 and July 2020 across three districts using a semi-structured questionnaire with a total of 120 informants. Chi-square and ANOVA were used to compute ethnoveterinary indices among agro-climates. A total of 95 plants in 44 families were used by the healers for treatments of 45 livestock ailments mostly collected from wild habitat (70.65%). The leaves (39.05%), and crushing and pounding were the major parts and modes of herbal preparations. The analysis unveiled a significant association between numbers of ethnoveterinary plant citations with sex (P= 0.001) and age categories (P=0.02). Also, considerable variations in medicinal plants distribution, Use Value (UV), Relative Frequency of Citations (RFC), and Fidelity Level (FL) were also observed among the studied agro-climates. Datura stramonium (UV= 0.85; FL=90.4%; RFCs=0.8) was the most often cited species to treat livestock ailments. Bloating (ICF= 0.87) and bloody diarrhea (ICF=0.85) were the most frequent livestock ailments. The studied districts are rich in medicinal floras and concomitant ethnoveterinary knowledge, and therefore essential to implement sustainable management and conservation of these plant genetic resources. [ABSTRACT FROM AUTHOR]

The land use and land cover (LULC) changes driven by the growing demands of mankind have a considerable effect on ecosystem services and functions. The study was carried out in the north-eastern highlands of Ethiopia to (1) analyze the effect of LULC changes between 1984 and 2021 and (2) assess the spatiotemporal variations in ecosystem service values (ESVs) and elasticity in response to LULC changes. Using Landsat imageries from 1984 to 2021, the spatiotemporal changes in LULC were evaluated with supervised image classification using maximum likelihood algorithm in ArcGIS software. Six LULC types were subsequently categorized, with overall accuracy and Kappa coefficients above 87% and 0.87, respectively. The ESVs were then estimated based on the Benefit Value Transfer (BVT) approach employing modified conservative value coefficients. The findings revealed a significant increase in cultivated land (9759.1ha) and built-up area (10174.41ha) during the stipulated periods and a drop in other land use types. The forest loss gradually decreased from 4.1% in the second period (1991–2001) to 0.58% in the third (2001–2021), compared to the first of the 1.1% conversion rates. Similarly, the proportion of grassland and water bodies steadily reduced over the stipulated periods, by 1.15% and 2.3% per annum, respectively. The overall loss of ESVs in the study landscape was estimated to be 54.4 million US$ (67.3%), drastically decreasing from 80.3 million US$ in 1984 to 26.4 million US$ in 2021, driven by the declining area coverage of water bodies, grassland, and forestland. Regardless of the loss, the ecosystem functions of hydrological regulation (37.2, 35.0, 6.1, and 5.1 US$ ha-1yr-1), water supply (14.5, 13.6, 2.4, and 2 US$ ha-1yr-1), and food production (9.8, 10.0, 9.1, and 9.9 US$ ha-1yr-1) contributed the most to the total ESV of each year while disturbance regulation and cultural values were the least throughout the study periods. The coefficient of sensitivity (CS) analysis revealed that our estimates were relatively robust. The findings further showed that human-dominated land-uses at the expense of natural ecosystems are the primary drivers of LULC transitions and the ensuing loss of ecosystem services in the region. Thus, this calls for intensive work on more effective land use policies that encourage an integrated management approach, with a focus on safeguarding the sustainability of natural ecosystems. [ABSTRACT FROM AUTHOR]

Background and Aims While variation in genome size and chromosome numbers and their consequences are often investigated in plants, the biological relevance of variation in chromosome size remains poorly known. Here, we examine genome and mean chromosome size in the cyperid clade (families Cyperaceae, Juncaceae and Thurniaceae), which is the largest vascular plant lineage with predominantly holocentric chromosomes. Methods We measured genome size in 436 species of cyperids using flow cytometry, and augment these data with previously published datasets. We then separately compared genome and mean chromosome sizes (2C/2 n) amongst the major lineages of cyperids and analysed how these two genomic traits are associated with various environmental factors using phylogenetically informed methods. Key Results We show that cyperids have the smallest mean chromosome sizes recorded in seed plants, with a large divergence between the smallest and largest values. We found that cyperid species with smaller chromosomes have larger geographical distributions and that there is a strong inverse association between mean chromosome size and number across this lineage. Conclusions The distinct patterns in genome size and mean chromosome size across the cyperids might be explained by holokinetic drive. The numerous small chromosomes might function to increase genetic diversity in this lineage where crossovers are limited during meiosis. [ABSTRACT FROM AUTHOR]

Psoraleeae consist of c. 228 species in ten genera, distributed worldwide but mostly in the temperate biome. Here, we reconstruct the phylogenetic history of Psoraleeae using eight molecular markers (rpl32-trnL , trnQ-rps16 , trnS-trnG , matK , rbcLa , rpoB-trnC , trnL-trnF and ITS) to test the monophyly and previous hypotheses on generic relationships and to reconstruct the biogeographical history (distribution pattern, potential ancestral area and biome). The monophyly of Psoraleeae is supported. The African Otholobium and Psoralea form a strongly supported clade that is sister to the rest of Psoraleeae. However, Otholobium is not monophyletic; the American taxa of the genus are resolved as closer to Bituminaria , whereas Psoralea is a clade derived from within African Otholobium. South African Otholobium is subsumed into Psoralea , the latter having priority, with a synopsis of species level nomenclature provided here. An expanded sampling of Cullen reveals three clades comprising Mediterranean (Cullen americanum), African (Cullen obtusifolium and Cullen biflorum) and Eurasian (Cullen corylifolium and Cullen drupaceum) taxa, whereas Australian Cullen are a derived clade (BS = 95%, PP = 1.00). Biogeographic reconstructions show that Psoraleeae probably originated in the Mediterranean south biome of Africa in the Late Miocene, c. 8.2 Mya, and then dispersed into the succulent biome of the Americas, Mediterranean north biome, temperate grasslands of Africa and Australia to the temperate forest of Eurasia. Climate changes in the Late Miocene, changes induced by ocean currents during the Quaternary and environmental heterogeneity are proposed as the major drivers of speciation in Psoraleeae. [ABSTRACT FROM AUTHOR]

Background: The Coronavirus (COVID-19) is a global pandemic caused by SARS-CoV-2, which has an enormous effect on human lives and the global environment. This review aimed to assess the global scientific evidence on the impact of COVID-19 lockdown on natural resources using international databases and search engines. Thus, the unprecedented anthropause due to COVID-19 has positive and negative effects on natural resources. Main body: This review showed that the unprecedented pandemic lockdown events brought a negative impact on the physical environment, including pollution associated with a drastic increase in person protective equipment, deforestation, illegal poaching and logging, overfishing, disruption of the conservation program and projects. It is noted that the spread of pandemic diseases could be aggravated by environmental pollution and a rapid increase in the global population. Despite these negative impacts of COVID-19, the anthropause appear to have also several positive effects on natural resources such as short term reduction of indoor and outdoor environmental pollutants (PM2.5, PM10, NO2, SO2, CO, and CO2), reduction in noise pollutions from ships, boats, vehicles, and planes which have positive effects on aquatic ecosystems, water quality, birds behaviour, wildlife biodiversity, and ecosystem restoration. Conclusion: Therefore, governments and scientific communities across the globe have called for a green recovery to COVID-19 and implement multi-actor interventions and environmentally friendly technologies to improve and safeguard sustainable environmental and biodiversity management and halt the next pandemic. [ABSTRACT FROM AUTHOR]

Interrogative proteome analyses are used to identify and quantify the expression of proteins involved in heat tolerance and to identify associated physiological processes in heat-stressed plants. The objectives of the study were to identify and quantify the expression of proteins involved in heat tolerance and to identify associated physiological processes in chickpea (Cicer arietinum L.) heat-tolerant (Acc#7) and sensitive genotype (Acc#8) from a field study. Proteomic and gene ontological analyses showed an upregulation in proteins related to protein synthesis, intracellular traffic, defence and transport in the heat-tolerant genotype compared to the susceptible one at the warmer site. Results from KEGG analyses indicate the involvement of probable sucrose-phosphate synthase (EC 2.4.1.14) and sucrose-phosphate phosphatase (EC 3.1.3.24) proteins, that were upregulated in the heat-tolerant genotype at the warmer site, in the starch and sucrose pathway. The presence of these differentially regulated proteins including HSP70, ribulose bisphosphate carboxylase/oxygenase activase, plastocyanin and protoporphyrinogen oxidase suggests their potential role in heat tolerance, at flowering growth stage, in field-grown chickpea. This observation supports unaltered physiological and biochemical performance of the heat-tolerant genotypes (Acc#7) relative to the susceptible genotype (Acc#8) in related studies (Makonya et al. 2019). Characterisation of the candidate proteins identified in the current study as well as their specific roles in the tolerance to heat stress in chickpea are integral to further crop improvement initiatives. Increased frequency and duration of high temperatures continues to limit crop development. An analysis of chickpea proteome to help uncover proteins and enzymes contributing to its heat tolerance and associated physiological processes is essential. Proteins related to protein synthesis, intracellular traffic, transport and defence were upregulated in heat-tolerant genotypes consistent with their previously unaltered physiological and biochemical performance. Identified candidate proteins and their specific roles in the tolerance to heat stress in chickpea are integral to further crop improvement initiatives. [ABSTRACT FROM AUTHOR]

In this study, Indigofera wenholdiae, a new species of Fabaceae from the Agulhas Plain Region of the Western Cape Province, South Africa, is described. A composite photographic plate is included along with a distribution map, description of habitat and ecology and proposed IUCN conservation status. Indigofera wenholdiae is unique in the I. brachystachya group by having digitately compound (vs. pinnately compound) leaves, white and unscented flowers (vs. pink and sweetly scented flowers) and grows on sandstone hillsides (vs. coastal limestone plains and outcrops). [ABSTRACT FROM AUTHOR]

Cyperaceae (sedges) are the third largest monocot family and are of considerable economic and ecological importance. Sedges represent an ideal model family to study evolutionary biology due to their species richness, global distribution, large discrepancies in lineage diversity, broad range of ecological preferences, and adaptations including multiple origins of C4 photosynthesis and holocentric chromosomes. Goetghebeur′s seminal work on Cyperaceae published in 1998 provided the most recent complete classification at tribal and generic level, based on a morphological study of Cyperaceae inflorescence, spikelet, flower, and embryo characters, plus anatomical and other information. Since then, several family‐level molecular phylogenetic studies using Sanger sequence data have been published. Here, more than 20 years after the last comprehensive classification of the family, we present the first family‐wide phylogenomic study of Cyperaceae based on targeted sequencing using the Angiosperms353 probe kit sampling 311 accessions. In addition, 62 accessions available from GenBank were mined for overlapping reads and included in the phylogenomic analyses. Informed by this backbone phylogeny, a new classification for the family at the tribal, subtribal, and generic levels is proposed. The majority of previously recognized suprageneric groups are supported, and for the first time, we establish support for tribe Cryptangieae as a clade including the genus Koyamaea. We provide a taxonomic treatment including identification keys and diagnoses for the 2 subfamilies, 24 tribes, and 10 subtribes, and basic information on the 95 genera. The classification includes five new subtribes in tribe Schoeneae: Anthelepidinae, Caustiinae, Gymnoschoeninae, Lepidospermatinae, and Oreobolinae. [ABSTRACT FROM AUTHOR]

The predominantly austral genus Schoenus L. is the largest genus in tribe Schoeneae and one of the ten most species‐rich Cyperaceae genera, with over 150 accepted species found mostly in Australia, New Zealand, southeast Asia, and southern Africa. Here, we use data based on two nuclear and three plastid DNA regions to present one of the most comprehensive phylogenetic reconstructions of a genus in Cyperaceae to date, covering over 70% of described species of Schoenus. After recent taxonomic realignments in the last 4 years have both added and removed species from the genus, we show that Schoenus is now monophyletic. In addition, our results indicate that Schoenus originated in Western Australia in the Paleocene and eventually dispersed to surrounding continents, but rarely back. The diversification rate of the genus appears to have slightly decreased over time, and there has not been an increase associated with the establishment of the Cape clade endemic to the sclerophyllous fynbos vegetation type, such as has been reported in other plant lineages endemic to the Cape region. These results will serve as a template to understanding the complex patterns of genome size evolution and to untangle drivers of diversification in this genus. [ABSTRACT FROM AUTHOR]