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Lampranthus consists of 85 species of succulent perennials which are all endemic to southern Africa. Most of its species are restricted to fynbos and regenerate in large numbers after fires. We use nine chloroplast markers to generate a phylogeny with a dense sampling of Lampranthus and some taxa which may be closely related to it. While we found that most of the species belong to one strongly supported "core" clade, we also found three minor clades of Lampranthus that fall outside this core. For Lampranthus we set up a new classification of three subgenera. The clades forming L. subg. Adunci (3 spp.) and subg. Calcarati (1 sp.) are unresolved within the Ruschieae and we treat them as subgenera until their relationships are clarified. Three sections are proposed for L. subg. Lampranthus and we also suggest new synonymy for several species in L. sect. Lampranthus (65 spp.) and sect. Blandi (15 spp.). Roosia and the type species for Esterhuysenia are nested in L. sect. Blandi and so these genera are subsumed under Lampranthus. Esterhuysenia stokoei forms part of Lampranthus and is the sole member of a new section within L. subg. Lampranthus. The two larger sections of L. subg. Lampranthus show different evolutionary trends and distributions: Lampranthus sect. Lampranthus contains more species, they are mostly in the winter rainfall region of the Western Cape and they have a greater range of floral shapes and colours. Lampranthus sect. Blandi contains a single species in the Kamiesberg, in the Northern Cape, while most of its species occur along the southern coast of southern Africa eastwards to southern Natal. These species are florally less diverse. Two species of Lampranthus are moved to a new genus, Malephoropsis gen. nov. These are unrelated to the rest of Lampranthus and they fall among species of Malephora, Disphyma and Gibbaeum with which they share softly corky branches, mesomorphic leaves and only slightly woody fruits with false septa. Several species, which were at one stage included in Lampranthus, are re‐instated in Ruschia; for four others, previously transferred out of Lampranthus to Esterhuysenia or Oscularia, but which cannot be accommodated into any of the existing genera, we propose a new genus, Sederbergia gen. nov. Lastly, we consider three monotypic genera which were sequenced here for the first time: Circandra is re‐instated in Erepsia; Malotigena is transferred to Delosperma subg. Proterogyna; the relationships of Daggodora remain unresolved. [ABSTRACT FROM AUTHOR]

Erica comprises ~860 species of evergreen shrubs and trees ranged from Europe to southern Africa and Madagascar. Wood structure of the around 20 European species is well studied, but despite its relevance to adaptation across the wider geographic range, it has not yet been explored across the much greater diversity, particularly of southern African lineages. In this study, we examine wood structure of 28 Erica species from southern Africa. In the African Erica clade, loss of scalariform perforation plates could be driven by increased aridity and seasonality in the mid-Miocene, and its re-gain can represent an adaptation to freezing in the high elevation species E. nubigena. As vessels in Erica are mostly solitary, imperforate tracheary elements probably form a subsidiary conduit network instead of vessel groups. Increase of ray frequency in habitats with a prominent dry and hot season probably facilitates refilling of vessels after embolism caused by water stress. Wider rays are ancestral for the lineage comprising African Erica and the Mediterranean E. australis. The negative correlation between ray width and expression of summer drought is consistent with Ojeda's model explaining the diversification of seeders and resprouters among southern African Erica. [ABSTRACT FROM AUTHOR]

A survey of vascular plant species occurring in various wetland habitats in South Africa has been generated by supplementing the species list from a vegetation survey with a herbarium checklist and this list of wetland species is compared with the overall flora of South Africa. About 18.8% of all the South African species occur in wetlands and about 4.5% of all species are obligate wetland species, in the sense that they will not be found outside of the wetland environment. These fractions are compared with the fractions calculated per family and this indicates which families are over- or underrepresented in the South Africa wetland flora. Most of the families that are well represented in wetlands are in the monocots and particularly in the Poales, but wetlands in the Fynbos Biome are much more phylogenetically diverse. There are four main wetland assemblages that can be defined by their family composition and that are characteristic of specific wetland environments. These can generally be described as the environments that are permanently submerged, the environments that are permanently to intermittently inundated, the environments of inland saline pans and environments on extremely nutrient-poor substrates consisting of coastal sands, quartzites or peat. [ABSTRACT FROM AUTHOR]

In the Cape Fynbos of South Africa, Psoralea pinnata (L.) plants occur naturally in both wetland and well-drained soils and yet effectively fix N under the two contrasting conditions. In this study, nodule structure and functioning in P. pinnata plants from the two habitats were evaluated using light and transmission electron microscopy (TEM), as well as the N natural abundance technique. The results showed that, structurally, fully developed P. pinnata nodules were spherical in shape with six components (namely, lenticels, periderm, outer cortex, middle cortex, inner cortex, and a central bacteria-infected medulla region). Morphometric analysis revealed 44 and 84 % increase in cell area and volume of wetland nodules compared to those from upland. The percentage area of nodules occupied by the middle cortex in wetland nodules was twice that of upland nodules. As a result, the size of the medulla region in wetland nodules was significantly reduced compared to upland nodules. Additionally, the average area of medulla occupied by intercellular air spaces in wetland nodules was about five times that of upland nodules (about 431 % increase in wetland over upland nodules). TEM data also showed more bacteroids in symbiosomes of upland nodules when compared to wetland nodules. However, isotopic analysis of above-ground plant parts revealed no differences in symbiotic parameters such as N concentration, ∂N and %Ndfa between wetland and upland P. pinnata plants. These results suggest that, under limiting O conditions especially in wetlands, nodules make structural and functional adjustments to meet the O demands of N-fixing bacteroids. [ABSTRACT FROM AUTHOR]

Urbanisation often has profound impacts on ecological processes. Management of these impacts is central to urban conservation efforts. We used data from 6591 individually ringed weaver birds from 42 ringing locations to investigate the influence that the urban matrix, as well as patch isolation, size and quality, had on weaver bird movement between ringing locations in Cape Town, a growing city within a global biodiversity hotspot. Distance-based linear models revealed that proximity to other sites was the dominant predictor of weaver movement while the site variables (wetland size and bird abundance) had a limited and inconclusive influence. Once the variation explained by the proximity and site variables had been accounted for, the composition of the surrounding urban matrix, the length of the least cost path between wetlands, and the presence of rivers as potential movement corridors (measured at three spatial scales) all had little influence on weaver movement. Analysis of the weaver bird movement-wetland network using social network analysis showed that the network is simple, clustered, and non-random, with relatively high vulnerability to node loss and some indication of preferential attachment (i.e., increased use of more used sites). Since proximity (site isolation) is the dominant influence on weaver movements, and the network is already sparse, further wetland loss is likely to reduce population viability. Our results match the predictions of classical theory and suggest that patch management will matter more for wetland passerines than matrix management. [ABSTRACT FROM AUTHOR]

The southern African landscape appears to have experienced frequent shifts in vegetation associated with climatic change through the mid-Miocene and Plio–Pleistocene. One group whose historical biogeography may have been affected by these fluctuations are the dwarf chameleons ( Bradypodion), due to their associations with distinct vegetation types. Thus, this group provides an opportunity to investigate historical biogeography in light of climatic fluctuations. A total of 138 dwarf chameleons from the Cape Floristic Region of South Africa were sequenced for two mitochondrial genes (ND2 and 16S), and resulting phylogenetic analyses showed two well-supported clades that are distributed allopatrically. Within clades, diversity among some lineages was low, and haplotype networks showed patterns of reticulate evolution and incomplete lineage sorting, suggesting relatively recent origins for some of these lineages. A dispersal-vicariance analysis and a relaxed Bayesian clock suggest that vicariance between the two main clades occurred in the mid-Miocene, and that both dispersal and vicariance have played a role in shaping present-day distributions. These analyses also suggest that the most recent series of lineage diversification events probably occurred within the last 3–6 million years. This suggests that the origins of many present-day lineages were founded in the Plio–Pleistocene, a time period that corresponds to the reduction of forests in the region and the establishment of the fynbos biome. [ABSTRACT FROM AUTHOR]

The robusticity of human long bone diaphyses can provide information about habitual behaviour among humans in the past. Mechanically relevant morphological variables include the strength of the diaphysis relative to body size, asymmetry between antimeres, diaphyseal shape, and sexual dimorphism in mechanical properties. This study compares the long bone robusticity of humeri, ulnae, femora and tibiae of Later Stone Age foragers from the forest and fynbos biomes of the southern African Cape region (n=65:32m,33f), dated primarily to between 8000 and 2000 BP. Ecological differences between these biomes dictate variation in the terrestrial resource base, although marine contributions to diet are significant throughout the Cape. Female robusticity remains relatively homogenous between the forest and fynbos biomes, and is characterized by relative symmetry in strength characteristics between paired upper limb elements with antero-posteriorly strengthened diaphyses. This morphology is consistent with shellfish harvesting and the use of digging sticks throughout the Later Stone Age in these regions. Male lower limb robusticity is consistently high in both biomes, suggesting that high levels of terrestrial mobility were characteristic of male subsistence strategies. The forest biome males have higher levels of bilateral asymmetry in upper-limb robusticity than males of the fynbos biome. This morphology may correspond with increased unilateral loading resulting from a higher frequency of use of spear projectiles relative to bows and arrows, and greater exploitation of medium to large sized bovids. [Copyright &y& Elsevier]

Abstract Fire is a key ecological process in several biomes worldwide. Although many conservation agencies have the protection of biodiversity as at least one of their major goals, information on the effects of fire on fauna in these biomes is fragmentary. Here we provide an overview of the published research undertaken to date on the effects of fire on fauna using examples from Southern Africa. We found that few studies have examined the effects of fire on amphibians or reptiles, and work on invertebrates is likewise sparse. The majority of studies that have been published are observational reports, and few experimental studies have been undertaken using an experimental fire regime, or over appropriately long time intervals. Replication was often not reported and where this was done, it was generally inadequate. The majority of the studies failed to report the area over which the studies were undertaken and sampling unit size was often not reported. Despite the importance of fire duration, ignition method, season and time of day of fire, few studies investigated these variables. We conclude that at present the information on the effects of fire on fauna in Southern Africa is fragmentary and, consequently, informed management decisions regarding the consequences of burning policies on the conservation of biodiversity both within and outside protected areas are problematic. We recommend that future studies, both in Southern Africa and elsewhere, be based on a suite of large-scale and experimental approaches (the latter firmly grounded in the principles of sound experimental design), use non-classical statistics to explore the effects of large-scale or unreplicated fires, and where possible include baseline information such as that gathered in fragmentation experiments. [ABSTRACT FROM AUTHOR]

• We recover a crown age of 18.7 (10.5–28.7) Mya for fynbos clade Phylica. • The fynbos vegetation was assembled during the whole Cenozoic. • Poor soils rather than climate underlie the biased composition of Cape heathlands. The Cape flora is compositionally biased, being dominated by a few fynbos clades (such as Iridaceae, Ericaceae, Proteaceae and Restionaceae) that make up major part of the distinct heathland vegetation in the Cape Floristic Region. Uncertainty exists concerning what excluded the subtropical to tropical palm-dominated woodland/forest vegetation that was the dominant component in the CFR in the Paleocene and allowed the fynbos clades, which are largely derived from outside Africa, to establish and radiate. Two filters have been proposed. The first postulates that the establishment of the Mediterranean climate driven by the late Miocene initiation of the cold-water Benguela Upwelling System (BUS) eliminated the African lineages and allowed the establishment and radiation of sclerophyllous plant clades ("the Mediterranean climate model", MCM). Alternatively, the "oligotrophic soils model" (OSM) postulates that the oligotrophic soils, gradually exhumed by post-Gondwanan Late Cretaceous – early Cenozoic erosion, acted as a filter excluding the African lineages. In this study, we re-calibrate the fynbos clade Phylica (Rhamnaceae), the genus initially used to test the MCM, using new fossil data to test if the crown age precedes the Late Miocene. Our results indicate that we cannot significantly reject a crown age of Phylica consistent with the MCM. We compare the MCM and OSM model for the Cape fynbos flora by compiling the crown ages of 22 fynbos clades. We show that crown ages are not clustered in time around the initiation of the BUS but, are dispersed throughout the Cenozoic. This suggests that oligotrophic soils, rather than summer drought, acted as a filter. Consequently, we argue that the fynbos clades radiated separately in expanding edaphically controlled heathland patches in the Cape mountains as sandstone exhumation after the Gondwanan break-up progressed. [ABSTRACT FROM AUTHOR]

Cover description: The Silver-edge Pincushion ( Leucospermum patersonii) occurs on limestone soils in the Agulhas region at the southern tip of Africa. It is one of 381 taxa of Proteaceae which occur in the species-rich Fynbos Biome of the Cape Floral Kingdom. They were the focus of a 10-year atlas project ( ) involving over 500 amateurs on the subcontinent, who collected over 250 000 records from 65 000 localities. For over 15 years proteas have been used to guide systemic and objective conservation planning and management in the region. Photo: Justine Grantham. [ABSTRACT FROM AUTHOR]