Malawi: closely related lake cichlids, white clay paintings at Chongoni and 845 hectares of Mulanje cedar

UNESCO places Lake Malawi National Park at the southern end of the lake and says it is home to many hundreds of cichlid species, nearly all of them endemic to the lake. For a 2018 genome study, Malinsky and colleagues sequenced 134 individuals from 73 species, using fin clips collected in Malawi and Tanzania between 2004 and 2014. Average sequence divergence between pairs of species was only 0.1–0.25%, a range that overlaps with the diversity found within species, and 82% of heterozygosity, the variation between an individual’s two sets of chromosomes, was shared between species. The authors divide the species into seven groups by ecology and body form, among them the rock-dwelling mbuna, the typically deep-water Diplotaxodon and the Copadichromis utaka, which feed in open water but breed on or near the bottom. Their analysis points to serial branching from a generalist ancestor resembling Astatotilapia, and no single species tree fits all the relationships, which they read as evidence of gene flow at multiple times.[2][1]

UNESCO lists 127 rock-art sites in the Chongoni Rock-Art Area, 126.4 km² of forested granite hills on the central plateau in Dedza District, with paintings by BaTwa hunter-gatherers and later ones by Chewa farmers. The Rock Art Research Institute at the University of the Witwatersrand describes the Chewa work as two traditions, chinamwali and nyau. The white paint is powdered clay dug from riverbeds, the same material still used to decorate houses, and it appears to have been mixed with water only. Chinamwali paintings, linked to the girls’ coming-of-age ceremony of the same name, are far more numerous, with more than a dozen superimposed layers at some sites; nyau paintings show masked figures and large animal basketwork figures and are known from only a few dozen sites. The institute says neither is made today, though some chinamwali shelters are still used for the ceremony; UNESCO adds that Chinamwali is still practised, mostly in secret, and that Nyau masked figures can be seen in most villages around Chongoni. UNESCO’s intangible heritage list also records Gule Wamkulu, the dance of the Chewa performed by members of the Nyau brotherhood in Malawi, Mozambique and Zambia.[3][4][5]

Bayliss and colleagues (2007) describe Mount Mulanje as rising above the plains of southern Malawi to more than 3,000 m over about 650 km², known locally as chilumba mu mlengalenga, the Island in the Sky, with tea estates along the southern and eastern edges of its forest reserve. The Mulanje cedar, Widdringtonia whytei, a conifer of the cypress family, is endemic to the massif. Their 2004 sample-plot survey found 30 cedar clusters in six regions, among them Chambe, Chinzama, Lichenya and Thuchila, covering 845.3 ha, and about a third of the recorded trees were dead. A 1989 survey had given 1,462 ha; the authors calculate a loss of 616.7 ha in 15 years but note that different methods make direct comparison difficult. The Royal Botanic Garden Edinburgh’s conifer profile gives an altitude range of 1830–2550 m and says that, unlike its relative Widdringtonia nodiflora, the cedar does not resprout from stumps burnt by fire and must regenerate from seed; it names more frequent fire as a barrier to regeneration and lists the species as Critically Endangered, where Bayliss and colleagues cited an Endangered listing from 2006.[6][7]