Guinea Highlands Research Articles

Seed and Germination Study of a New Guinea Endemic Plant Species <i>Grevillea papuana</i> Diels.

Grevillea papuana is a culturally important endemic plant species of New Guinea highland. Although G. papuana conservation and propagation attempts were already conducted, this species seed and germination characters information were still very limited. This study aimed to provide information regarding G. papuana seed and germination biology. Seed characteristic and germination trials were conducted in this study. Data analysis was conducted descriptively, while germination parameters were also calculated. G. papuana has a light, elliptic, and winged seed. The species germination was low and ununiform with phanerocotylar epigeal foliaceous (PEF) seedling functional type.

On Vortices Initiated over West Africa and Their Impact on North Atlantic Tropical Cyclones

AbstractUsing 38 years of the ERA-Interim dataset, an objective tracking approach is used to analyze the origin, characteristics, and cyclogenesis efficiency (CE) of synoptic-scale vortices initiated over West Africa and the Atlantic Ocean. Vortices initiated over the ocean at a given pressure level often result from a vertical expansion of a “primary” vortex track initiated earlier over West Africa. Low-level (850 hPa) primary vortices are initiated mainly in July near the Hoggar Mountains (24°N, 5°E), while midlevel (700 hPa) primary vortices are initiated mainly in August–September near the Guinea Highlands (10°N, 10°W). The CE of all these vortices is about 10% in July and 30% in August. The average CE is, however, smaller for low-level “Hoggar” vortices because they peak in July when the cyclogenesis potential index of the Atlantic Ocean is weak. Seasonal and interannual modulations of the cyclogenesis is related more to this index than to the number of vortices crossing the West African coast. Cyclogenesis is nearly equally distributed between the coast and 60°W, but the part of the cyclogenesis due to vortices initiated over West Africa decreases from 80% near the coast to about 30% at 60°W. The most probable delay between the vortex vertical expansion and cyclogenesis is 2 days, but it can be up to 10 days. This analysis also confirms previous results, such as the larger CE for vortices extending at low levels over the continent at 10°N, or the delayed and therefore west-shifted cyclogenesis of low-level “Hoggar” vortices.

Elevation is a stronger predictor of morphological trait divergence than competition in a radiation of tropical lizards.

Adaptations for efficient performance are expected to shape animal morphology based on selection for microhabitat use and ecological forces. The presence of competitor species is predicted to cause niches to contract and enhance trait divergence. Therefore, increased species richness is expected to lead to greater trait divergence, and to result in reduced overlap and similarity between morphologies of sympatric species. We examined patterns of morphospace occupancy and partitioning in the skink fauna of New Guinea, the world's largest tropical island. Because skink species richness is largely decoupled from elevation in New Guinea, we could examine the effects of both factors (as proxies for competition and abiotic conditions), on morphospace occupancy and partitioning. We measured 1,860 specimens from 79 species of skinks throughout Papua New Guinea, and examined their morphospace occupancy in a spatial context. We calculated, for each assemblage within equal-area cells, the volume of morphospace occupied by all skinks, the mean volume occupied per species, and the mean distance and overlap between all species pairs. We then examined whether these metrics are related to species richness and elevation. Elevation is a stronger predictor of morphospace occupancy than species richness. As elevation increases, intraspecific variation decreases and morphologies become more similar to each other such that overall morphospace occupancy decreases. Highland skinks are, on average, smaller, thinner and shorter limbed than lowland species. We hypothesise that harsh climates in the New Guinea highland habitats impose strong selection on skinks to occupy specific areas of morphospace that facilitate efficient thermoregulation in suboptimal thermal conditions. We conclude that the effect of competition on trait divergence on a community and assemblage scale is eclipsed by abiotic selection pressures in these harsh environments.

Small game hunting in montane rainforests: Specialised capture and broad spectrum foraging in the Late Pleistocene to Holocene New Guinea Highlands

Moving into montane rainforests was a unique behavioural innovation developed by Pleistocene Homo sapiens as they expanded out of Africa and through Southeast Asia and Sahul for the first time. However, faunal sequences from these environments that shed light on past hunting practices are rare. In this paper we assess zooarchaeological evidence from Yuku and Kiowa, two sites that span that Pleistocene to Holocene boundary in the New Guinea Highlands. We present new AMS radiocarbon dates and a revision of the stratigraphic sequences for these sites, and examine millennial-scale changes to vertebrate faunal composition based on NISP, MNI, and linear morphometric data to shed light on variability in hunting practices, processes of natural cave deposition, and the local palaeoenvironment at the end of the LGM through to the Late Holocene. We show that Yuku was first occupied at least c. 17,500 years ago and that Late Pleistocene–Early Holocene hunters targeted a wide range of small-bodied and agile species from the mid-montane forest, with a particular focus on cuscus (Phalanger spp.). At Kiowa, occupied from around 12,000 years ago, a similar range of species were targeted, but with an added emphasis on specialised Dobsonia magna fruit bat hunting. We then integrate other zooarchaeological data from the wider Highlands zone to build a model of generalist-specialist hunting dynamics and examine how this more broadly contributes to our understanding of tropical foraging during the Late Pleistocene and Holocene.

Modeling Past and Present in the Eastern Highlands of Papua New Guinea

The existence of “fringe societies” in Papua New Guinea has long been recognized by anthropologists. In the New Guinea Highlands, the term refers to peoples who occupy the fringes of more populous and better-known valleys. In many instances, these groups also subsist on staples other than Ipomoea batatas, more commonly known as sweet potato, a tuber introduced to the highlands within the last 300 years. The Awa at the far eastern edge of the Eastern Highlands are such a group, and the word fringe has often been used to describe them. Surprisingly, anthropologists and archaeologists have not seized on the possibility that their unusual subsistence represents a survival of a previous adaptation that has not completed its conversion to the new crop. The authors of this paper use the Awa economy to model a pre-ipomoean past for members of the Tairora language subfamily, namely, the South Tairora, Auyana, and Awa languages. Using archaeological, paleoenvironmental, demographic, and ethnohistorical data from our study area; data for Awa from ethnographer David Boyd’s research; and other sources and simulation modeling, we explore long-standing questions about the dispersal of early horticultural peoples, its determinants, the differentiation of languages, possible time frames for their migrations, and impacts on the resulting landscapes.

A continuation of warfare by sportive means: settling conflicts through football in the Eastern Highlands of colonial New Guinea

ABSTRACT This ethnohistorical study of football games from the mid-1940s to the 1970s in the Eastern Highlands of Papua New Guinea explores the potentials and limits of using sport as a conflict-settlement measure. Football was introduced by Australian colonial officers as a peacebuilding exercise, and local communities quickly adapted it to settle conflicts that otherwise could have escalated to war. It was a new mechanism to redress perceived violations and injustices but culturally shaped by pre-existing experiences and understandings. The game, similar to warfare, only came to a conclusion when both sides were exhausted, and the scores considered even. Football thus served a useful purpose to settle conflicts peacefully and efficiently – within limits. Tensions and emotions ran high on the football pitch, resulting in instances where games led to the renewed outbreak of inter-village wars, especially when the underlying ethos of equivalence was breached, and one side dominated the match.

West African Summer Monsoon Precipitation Variability as Represented by Reanalysis Datasets

Focusing on West Africa, a region riddled with in situ data scarcity, we evaluate the summer monsoon monthly rainfall characteristics of five global reanalysis datasets: ERA5, ERA-Interim, JRA-55, MERRA2, and NCEP-R2. Their performance in reproducing the West African monsoon (WAM) climatology, interannual variability, and long-term trends for the main monsoon months are compared to gauge-only and satellite products. We further examine their ability to reproduce teleconnections between sea surface temperatures and monsoon rainfall. All reanalyses are able to represent the average rainfall patterns and seasonal cycle; however, regional biases can be marked. ERA5, ERA-Interim, and NCEP-R2 underestimate rainfall over areas of peak rainfall, with ERA5 showing the strongest underestimation, particularly over the Guinea Highlands. The meridional northward extent of the monsoon rainband is well captured by JRA-55 and MERRA2 but is too narrow in ERA-Interim, for which rainfall stays close to the Guinea Coast. Differences in rainband displacement become particularly evident when comparing strong El Niño Southern Oscillation (ENSO) years, where all reanalyses except ERA-Interim reproduce wetter Sahelian conditions for La Niña, while overestimating dry conditions at the coast except for NCEP-R2. Precipitation trends are not coherent across reanalyses and magnitudes are generally overestimated compared to observations, with only JRA-55 and NCEP-R2 displaying the expected positive trend in the Sahel. ERA5 generally outperforms ERA-Interim, highlighting clear improvements over its predecessor. Ultimately, we find the strengths of reanalyses to strongly vary across the region.

Gut microbiota composition in obese and non-obese adult relatives from the highlands of Papua New Guinea.

Obesity is a condition that results from an imbalance between energy intake and expenditure. Recently, obesity has been linked to differences in the composition of gut microbiota. To examine this association in Papua New Guinea (PNG) highlanders, fecal samples were collected from 18 adults; nine obese participants were paired with their non-obese relative. Amplification of the 16S rRNA gene targeting the V1-V2 region was performed on DNA extracts for each participant, with high-quality sequences selected and used for operational taxonomic unit clustering. The data showed Firmicutes and Bacteroidetes were the two dominant phyla, while at genus level Prevotella was the most dominant genus in all of the samples. Nonetheless, statistical evaluation of potential association between nutritional status and bacterial abundance at both phyla and genus levels showed no significant difference. Further studies, ideally in both rural and urban areas, are needed to evaluate the role of the gut microbiome in the occurrence of obesity in PNG and other resource-limited settings.

New Guinea Erythrura parrotfinches: one species or two?

Two species of Erythrura parrotfinches, differing mainly in bill size, are described from the New Guinea highlands: Blue-faced Parrotfinch E. trichroa and Papuan Parrotfinch E. papuana. Morphological measurements from museum specimens support two non-overlapping groups, but mitochondrial DNA sequence data show negligible differences between the two species. These observations suggest that E. trichroa and E. papuana may form a single species in the highlands of New Guinea that exhibits a resource-based bill size polymorphism.

Orographic effects on the propagation and rainfall modification associated with the 2007–08 Madden–Julian oscillation (MJO) past the New Guinea Highlands

Based on the tropical rainfall measuring mission (TRMM)-measured rainfall and estimated outgoing longwave radiation (OLR) fields, it is found that 2007–08 Madden–Julian Oscillation (MJO07-08) went through blocking, splitting, and merging stages when it passed over the New Guinea Highlands (NGH). The TRMM-estimated OLR fields fail to capture detailed TRMM rainfall field and thus is not suitable to serve as proxy for rainfall, as also found in previous studies. The mechanism of orographic blocking is explained by strong orographic blocking on the incoming, low-Froude number, and moist flow, which belonged to the flow-around regime. This is evidenced by estimating the Froude number by upstream soundings. The strong blocking forced the flow to go around the mountains on NGH, leading to the splitting of flow and MJO precipitating system and the merging at the southeast tip of New Guinea. Orographic, MJO, and cyclone clouds were shown in both observed and model-simulated results. The major differences of the model-simulated and TRMM-measured precipitation are as follows: (a) the model-simulated rainfall area is much larger than that covered by the observed rainfall and (b) even though they both show comparable maximum rainfall rate, the rainfall estimated by TRMM reveals more localized rainfall spots, which is unexpected since the WRF simulation uses a relatively fine resolution (5 km). In summary, during the blocking stage, the mountains have slowed down the MJO propagation and increased the rainfall amount upstream of the local mountains, while during the splitting and merging stages, the mountains have made significant impacts on the MJO rainfall distribution.

Mountain linguistics

AbstractLanguage use in mountainous areas often exhibits special social dynamics. This contribution sketches some of the most salient patterns of language use in upland Southeast Asia ,the greater Himalayas, the Caucasus, the Central Andes, the New Guinea highlands, and touches upon the Alps and some highland areas of Africa and North America. Accumulated over long time, such patterns of use yield particular—often highly diverse, fragmented, and discontinuous—distributions of languages and language families in geographical space the precise characteristics of which also depend on prevailing local sociolinguistic and socioeconomic conditions. Generalization are still difficult since most observations are anecdotal rather than systematic: as far as language structure is concerned, languages spoken in mountainous regions are traditionally often attributed a “conservative” or “archaic” character, preserving inherited traits and patterns that are lost elsewhere; the inaccessibility of the terrain and the resulting relative social isolation are commonly invoked to explain this situation. More recently, mountain languages have also been claimed to feature peaks in the distribution of some typological properties, whether due to sociogeographical factors or, more controversially, even direct influences of the environment: ejectives, grammatical encoding of elevational or topographic information, and overall high levels of structural complexity.

Hibiscus fabiana sp. nov. (Malvaceae) from the Guinea Highlands (West Africa)

Hibiscus fabiana Cheek (sect. Furcaria, Malvaceae) is described from the Guinea Highlands of West Africa, and its taxonomic affinities and ecology are considered. Hibiscus fabiana has previously been confused with H. rostellatus but has red fleshy calyx ribs (vs not red and non-fleshy), the calyx surface is glabrous apart from 1-armed bristles (vs densely covered in minute white stellate hairs and bristles 2–5-armed), the leaves 3(–5)-lobed, bases truncate to rounded (vs 5-lobed, cordate). The conservation status of the new species is assessed using the IUCN 2012 standard as Vulnerable. In the context of the recently discovered extinction of the Guinean endemic Inversodicraea pygmaea G. Taylor (Podostemaceae), we discuss the 30 new species to science discovered in Guinea since 2005, all but one of which are also range-restricted and threatened, usually by development or habitat loss. We consider it urgent to avoid their extinction, ideally with in situ conservation using an Important Plant Areas approach.

Marital sexual violence and conjugality in highlands Papua New Guinea

Many male coffee farmers in the highlands of Papua New Guinea believe they have a right to sex with their spouse without regard to her wishes. Drawing on quantitative and qualitative data, I argue that such sexual violence is best framed within local understandings of what marriage involves – an implicit contract which conveys rights and responsibilities to each partner in a marriage. Changes brought by modernity are transforming traditional understandings of conjugality, causing some discrepancies in partners’ understanding of what they have agreed to. Too many women continue to endure marital rape, but some signs of improvement are discernible.

The Syntax and Semantics of Clause-Chaining in Toposa

Some languages make extensive use of clause-chaining. According to Payne (1997: 312), clause-chaining has been documented for languages in the highlands of New Guinea, Australia and the Americas. In Africa it is found in Ethiopia (Völlmin et al. 2007), in Kiswahili, a Bantu language (Hopper 1979: 213-215, Mungania 2018), in Anuak, a Western Nilotic language (Longacre 1990: 88-90 and 2007: 418) and in Toposa, a VSO language of South Sudan (Schröder 2011). Clause-chaining is characterized by a long combination of non-finite clauses that have operator dependency on a finite clause, and it usually signals foregrounded information in discourse (see also Dooley 2010: 3). Besides its discourse function, clause-chaining exhibits morpho-syntactic and semantic properties as demonstrated in this paper with examples from Toposa, an Eastern Nilotic language.

Functional studies of flaked and ground stone artefacts reveal starchy tree nut and root exploitation in mid-Holocene highland New Guinea

Ground stone technology for processing starchy plant foods has its origins in the late Pleistocene, with subsequent intensification and transformation of this technology coinciding with the global emergence of agriculture in the early Holocene. On the island of New Guinea, agriculture first emerges in the highland Wahgi Valley, potentially from c. 9 kya, and clearly evident by 6.5 kya. Approximately 400 km further east in the highland Ivane Valley, long-term occupation sequences span the Holocene and late Pleistocene, but there is currently no direct evidence for wetland agriculture. Here, we report rare evidence for ground stone implements from a secure mid-Holocene archaeological context in the Ivane Valley. The Joe’s Garden site has flaked and ground stone artefacts with significant starch assemblages dating to approximately 4.4 kya. We present the first empirical evidence for the function of stone bowls from a New Guinea highland setting. Usewear and residues indicate the grinding and pounding of endemic starch-rich plant foods. Geometric morphometric analysis of starch grains shows that at least two taxa were processed: Castanopsis acuminatissima (nut) and Pueraria lobata (tuber). This regional example adds to our understanding of the trajectories of diverse plant food exploitation and ground stone technology development witnessed globally in the Holocene.

Emergence of a Neolithic in highland New Guinea by 5000 to 4000 years ago.

The emergence of agriculture was one of the most notable behavioral transformations in human history, driving innovations in technologies and settlement globally, referred to as the Neolithic. Wetland agriculture originated in the New Guinea highlands during the mid-Holocene (8000 to 4000 years ago), yet it is unclear if there was associated behavioral change. Here, we report the earliest figurative stone carving and formally manufactured pestles in Oceania, dating to 5050 to 4200 years ago. These discoveries, at the highland site of Waim, occur with the earliest planilateral axe-adzes in New Guinea, the first evidence for fibercraft, and interisland obsidian transfer. The combination of symbolic social systems, complex technologies, and highland agricultural intensification supports an independent emergence of a Neolithic ~1000 years before the arrival of Neolithic migrants (Lapita) from Southeast Asia.

Recent kuru-induced female gene flow disrupted the coevolution of genes and languages in the Papua New Guinea highlands.

The island of New Guinea was settled by modern human over 50,000 years ago, and is currently characterized by a complex landscape and contains one-seventh of the world's languages. The Eastern Highlands of New Guinea were also the home to the devastating prion disease called kuru that primarily affected Fore-speaking populations, with some 68% of cases involving adult females. We characterized the mitochondrial DNA (mtDNA) diversity of highlanders from Papua New Guinea (PNG) to: (a) gain insight into the coevolution of genes and languages in situ over mountainous landscapes; and (b) evaluate the recent influence of kuru mortality on the pattern of female gene flow. We sequenced the mtDNA hypervariable segment 1 of 870 individuals from the Eastern and Southern Highlands of PNG using serums collected in the 1950s to 1960s. These highlanders were selected from villages representing 15 linguistic groups within the Trans-New Guinea phylum. Genetic, linguistic, and geographic distances were calculated separately and correlations among those distance matrices were assessed using the Mantel test. Geographic, genetic, and linguistic patterns were independently correlated with each other (p < .05). Increased mtDNA diversity in kuru-affected populations and low Fst estimates between kuru-affected linguistic groups were observed. In general, the genetic structure among the Highland populations was shaped by both geography and language, and language is a good predictor of mtDNA affinity in the PNG Highlands. High kuru female mortality increased female gene flow locally, disrupting coevolutionary pattern among genes, languages, and geography.

First records of 31 species of butterflies and moths (Lepidoptera) in Cameroon, with remarks on their elevational ranges.

BackgroundThe biodiversity of West and Central Africa is understudied, including butterflies and moths (Lepidoptera). Cameroon, through its position in between few biogeographic regions and diversity of habitats, is an important hotspot of lepidopteran diversity. However, the country also ranks low when it comes to local biodiversity knowledge. During our long-term ecological projects in the Cameroonian part of the Gulf of Guinea Highlands, we collected rich material of butterflies and moths, including a number of interesting faunistic records.New informationIn this study, we report 31 species of butterflies and moths which have not yet been recorded in Cameroon. These species comprised eight new genera records for the country. In many cases, our records represented an important extension of the species’ known distribution, including ten species whose distribution ranges extended into the Guinean biogeographic region. We also comment on the species’ elevational distribution ranges on Mount Cameroon where most of our records originated. Additionally, we confirm the presence of a butterfly Telchinia encedena, after more than a century since its first and so far its only record in Cameroon.

A first look at oxygen isotope records from modern and Holocene‐aged gastropod (Stenomelania) shells from Lake Kutubu, Papua New Guinea

ABSTRACTThe oxygen isotopic composition of Stenomelania gastropod shells was investigated to reconstruct Holocene palaeoclimate change at Lake Kutubu in the southern highlands of Papua New Guinea. Oxygen isotope (δ18O) values recorded in aquatic gastropod shells change according to ambient water δ18O values and temperature. The gastropod shells appear to form in oxygen isotopic equilibrium with the surrounding water and record a shift in average shell oxygen isotopic composition through time, probably as a result of warmer/wetter conditions at ca. 600–900 and 5900–6200 cal a bp. Shorter term fluctuations in oxygen isotope values were also identified and may relate to changes in the intensity or source of rainfall. Further δ18O analyses of gastropod shells or other carbonate proxies found in the Lake Kutubu sediments are warranted. © 2020 John Wiley &amp; Sons, Ltd.

Responses of Different Explants of Sweet Potato on Modified MS and LS Based Nutrient Media in vitro

A good number of reports on sweet potato (Ipomoea batatas L.) tissue culture using different tissues of various cultivars with varying level of efficiency and reproducibility are available but callus induction and plantlet regeneration are recalcitrant and limited to a few genotypes in response to different treatments in vitro. Reported in this paper is a procedure in which several explants of three high yielding and drought tolerant sweet potato cultivars (SK010, WHCH005 and PRAP496), mostly grown and cultivated in the highlands of Papua New Guinea (PNG) were used to induce embryogenic callus and regenerate plantlets. To achieve a reliable and an efficient system for inducing embryogenic callus on stem, petiole and leaf disc explants, a modified form of Murashige and Skoog (MS) and Linsmaier and Skoog (LS) media, supplemented with 1 gL-1 picloram and 8 gL-1 agar was used. This procedure resulted in large amount of embryogenic calli that were potentially capable of regenerating whole plantlets on all the different types of explants tested. Further attempts made in plantlet regeneration failed, however ways in which improvement of the tested regeneration media can be made for plant regeneration in similar studies were discussed.