Guinean Region Research Articles

Diversity, Geographical, and Consumption Patterns of Traditional Vegetables in Sociolinguistic Communities in Benin: Implications for Domestication and Utilization1

Diversity, Geographical, and Consumption Patterns of Traditional Vegetables in Sociolinguistic Communities in Benin: Implications for Domestication and Utilization. Traditional vegetables in many African rural areas are an important part of the daily diet and economy but have been poorly documented until recently. We undertook a survey in Benin on the diversity and patterns of use of traditional vegetables by 18 sociolinguistic groups in the three major phytogeographical regions. Major groups include the Yoruba–Nagot, Fon, Bariba, Adja, Cotafon, and Ditammari. Focus groups and field visits were conducted in 49 villages. Species richness at the country level and in phytogeographical regions was estimated using species accumulation curves. Our results indicated that 245 species belonging to 62 families are used as vegetable resources all over the country. The most frequently used families include Amaranthaceae, Asteraceae, Cucurbitaceae, and Leguminoseae. About 80% of collected vegetables are wild resources; only 19% were clearly under cultivation. Herbs were the most widely consumed life form. The Guinean and the Sudanian regions exhibit similar species richness while in the Sudano–Guinean region vegetable richness is higher. The use of a species as a vegetable depends not only on socio–cultural attributes but also on geographical occurrence. Based on this inventory, we identified needs for further research and activities for both the conservation and promotion of traditional vegetables.

Comparison of Rainfall Profiles in the West African Monsoon as Depicted by TRMM PR and the LMDZ Climate Model

Abstract Vertical rainfall profiles obtained with TRMM-PR 2A25 standard products are compared with rain profiles deduced from the Laboratoire de Météorologie Dynamique second generation global climate model (LMDZ, the Z stands for zoom capability) with two parameterization schemes: Emanuel’s and Tiedke’s. This paper focuses on the low layers of the atmosphere over West Africa during the monsoon [June–September (JJAS)]. The precipitation decrease above 4 km is systematically not represented in rainfall profiles generated by Emanuel’s parameterization scheme. However, Emanuel’s scheme shows a decrease similar to the observation from 4 km down to the surface, especially in the Sahel (proper depth of the layer dominated by reevaporation). As for Tiedtke’s scheme, it best describes the downward increase in the upper levels of the atmosphere, whereas the downward decrease in the lower levels begins too low when compared to the observations. Tiedtke’s parameterization shows an overestimation of liquid water production over the ocean and over the Guinean region and a slightly too strong reevaporation in the Sahara and Sahel. The zonal distribution of vertical rain profiles is then biased with this model scheme compared to the 2A25-PR product. On the other hand, although Emanuel’s scheme detects too much reevaporation over the Sahara and underestimates liquid water production over the ocean compared to PR observation, it shows a good meridional distribution of these parameters. This is especially true in the Sahel where Emanuel’s scheme gives the best representation of reevaporation.

WRF/ARPEGE-CLIMAT simulated climate trends over West Africa

The Weather Regional Forecast (WRF) model is used in this study to downscale low-resolution data over West Africa. First, the performance of the regional model is estimated through contemporary period experiments (1981–1990) forced by ARPEGE-CLIMAT GCM output (ARPEGE) and ERA-40 re-analyses. Key features of the West African monsoon circulation are reasonably well represented. WRF atmospheric dynamics and summer rainfall compare better to observations than ARPEGE forcing data. WRF simulated moisture transport over West Africa is also consistent in both structure and variability with re-analyses, emphasizing the substantial role played by the West African Monsoon (WAM) and African Easterly Jet (AEJ) flows. The statistical significance of potential climate changes for the A2 scenario between 2032 and 2041 is enhanced in the downscaling from ARPEGE by the regional experiments, with substantial rainfall increases over the Guinea Gulf and eastern Sahel. Future scenario WRF simulations are characterized by higher temperatures over the eastern Tropical Atlantic suggesting more evaporation available locally. This leads to increased moisture advection towards eastern regions of the Guinea Gulf where rainfall is enhanced through a strengthened WAM flow, supporting surface moisture convergence over West Africa. Warmer conditions over both the Mediterranean region and northeastern Sahel could also participate in enhancing moisture transport within the AEJ. The strengthening of the thermal gradient between the Sahara and Guinean regions, particularly pronounced north of 10°N, would support an intensification of the AEJ northwards, given the dependance of the jet to the position/intensity of the meridional gradient. In turn, mid-tropospheric moisture divergence tends to be favored within the AEJ region supporting southwards deflection of moist air and contributing to deep moist convection over the Sahel where late summer rainfall regimes are sustained in the context of the A2 scenario regional projections. In conclusion, WRF proved to be a valuable and efficient tool to help downscaling GCM projections over West Africa, and thus assessing issues such as water resources vulnerability locally.

Sensitivity of the West African hydrological cycle in ORCHIDEE to infiltration processes

Abstract. The aim of this article is to test the sensitivity of the West African hydrological cycle to infiltration processes and to river reinfiltration pathways. This is done through sensitivity experiments to both inputs and paramterization settings of the ORCHIDEE Land-Surface Model. The parameterizations to take into account the effects of flat areas, ponds and floodplains on surface infiltration, and the effect of roots and deep-soil compactness on infiltration are first described. The sensitivity analysis to parameterization settings shows that the surface infiltration processes have a stronger impact in the soudano-sahelian region and more generally in semi-arid African regions, whereas the rootzone and deep-soil infiltration also play a role in the guinean and intermediate regions between arid and humid ones. In the equatorial and semi-humid regions, infiltration processes generally play a minor role. The infiltration parameterizations may explain part of the difference between simulated and observed river discharge in semi-arid and intermediate basins. The sensitivity analysis to the Land-Surface Model inputs shows that different sources of uncertainty might also explain part of the error. Indeed, the precipitation forcing in the whole West African region, the long-term storage in the soudano-sahelian region, the soil types in the guinean region and the vegetation types in the equatorial region are significant sources of errors. Therefore, observations and analyses of small scale infiltration processes as well as continuous measurements of river discharges in West Africa are essential to ensure the reliability of future calibration for the infiltration parameterizations.

Simulation of West African monsoon using RegCM3 Part II: impacts of deforestation and desertification

In this study, we investigate the feedback mechanisms between land cover and the monsoon in West African using the International Centre for Theoretical Physics Regional Climate Model (RegCM3). A series of multi-year simulations are performed using reanalysis boundary conditions under three idealised vegetation states (potential, desertified and deforested). The study shows that both desertification and deforestation tend to increase the monsoon flow over the Guinean region, although the mechanisms for change are different in each case. Desertification increases the flow mainly by increasing the meridional temperature gradient. While this reduces rainfall over the desertification region, it increases rainfall to the south. On the other hand, deforestation increases the monsoon flow mainly due to the reduced surface friction experienced by the flow over the Guinean region. This reduces rainfall over the entire West African region. The study further shows that desertification and deforestation also increase the speed and specific humidity of the mid-tropospheric easterly flow, to the south of the African easterly jet. Consequently, the flow transports more moisture away from the West Africa region at the expense of low-level moisture, resulting in less moisture available for rainfall over the region. Overall, this study suggests that the state of the biosphere in West Africa may play an important role in determining the characteristics of the monsoon and rainfall pattern.

Impacts of bark and foliage harvest on Khaya senegalensis (Meliaceae) reproductive performance in Benin

Summary Increasing concern over the sustainability of harvesting non‐timber forest products (NTFP) has led to a growing literature on the ecological impacts of NTFP extraction. A large proportion of NTFP are harvested for multiple plant parts, but few studies have assessed the impacts of harvesting multi‐use species. In addition, few studies have assessed how harvest effects may vary across space. This information is necessary for designing effective conservation plans for the many NTFP species that are harvested from variable ecological contexts. This study assessed the impacts of combined bark and foliage harvest on Khaya senegalensis (Meliaceae) reproductive performance in Benin. K. senegalensis bark is an important medicine for malaria, the leaves are pruned by indigenous Fulani herders as a critical source of fodder for their livestock, and the timber is highly prized. Data on reproductive characteristics were collected from 12 populations spread across two ecological regions (Sudanian and Sudano–Guinean). Half the populations had a history of high harvest intensity and half were subject to low/no harvest. Trees produced more fruit and began fruiting at a significantly smaller size in the drier Sudanian region than in the wetter Sudano–Guinean region. However, pruning decreased fruit production significantly in the Sudanian region but not in the Sudano–Guinean region. Pruning had a significantly greater impact on fruit production in larger trees than in smaller trees. High harvest populations in the Sudano–Guinean region had significantly higher rates of seed production than low harvest populations, although the seeds were significantly lighter. There were no significant effects of debarking or combined debarking and pruning on reproductive performance. Synthesis and applications. This study illustrates that heavy rates of foliage harvest can decrease rates and patterns of reproduction in K. senegalensis, and that the impacts may vary across environmental contexts. Lowered rates of reproduction may lead to decreases in K. senegalensis population size over the long term. Effective ex situ conservation strategies for K. senegalensis include increasing the availability of its fodder and bark by promoting K. senegalensis plantations programmes involving Fulani harvesters.

Characterization of the Interannual and Intraseasonal Variability of West African Vegetation between 1982 and 2002 by Means of NOAA AVHRR NDVI Data

AbstractThe interannual and intraseasonal variability of West African vegetation over the period 1982–2002 is studied using the normalized difference vegetation index (NDVI) from the Advanced Very High Resolution Radiometer (AVHRR).The novel independent component analysis (ICA) technique is applied to extract the main modes of the interannual variability of the vegetation, among which two modes are worth describing. The first component (IC1) describes NDVI variability over the Sahel from August to October. A strong photosynthetic activity over the Sahel is related to above-normal convection and rainfall within the intertropical convergence zone (ITCZ) in summertime and is partly associated with colder (warmer) SST in the eastern tropical Pacific (the Mediterranean). The second component (IC2) depicts a dipole pattern between the Sahelian and Guinean regions during the northern summer followed by a southward-propagating signal from October to December. It is associated with a north–south dipole in convection and rainfall induced by variations in the latitudinal location of the ITCZ as a response to the occurrence of the tropical Atlantic dipole.The analysis of the intraseasonal variability of the Sahelian vegetation relies on the analysis of the seasonal marches and their main phenological stages. Green-up usually starts in early July and shows a very low year-to-year variability, while senescence ends by mid-November and is prone to larger interannual variability. Six types of vegetative seasonal marches are discriminated according to variations in the timing of phenological stages as well as in the greening intensity. These types appear to be strongly dependent on rainfall distribution and amount, particularly those recorded in late August. Finally, year-to-year memory effects are highlighted: NDVI recorded during the green-up phase in year j appears to be strongly related to the maximum NDVI value recorded at year j − 1.

Does a ruderal strategy dominate the endemic flora of the West African forests?

AbstractAim To understand the distribution pattern of endemic plant species in West African rain forests, one of the global priority areas for biodiversity conservation.Location Upper Guinean forests, West Africa (Senegal, Guinea‐Bissau, Guinea, Sierra Leone, Liberia, Côte d'Ivoire, Ghana and Togo).Methods We used herbarium collections from the whole Upper Guinean region (sensuWhite 1981) to analyse the distribution patterns of 216 vascular plant species (approximately one‐third of the endemic flora ranging from herbs to trees) that are restricted to these rain forests. We related species distribution ranges and species commonness to the main environmental variables and species life‐history traits.Results We found that most endemic species of West African forests have large distribution ranges and ruderal strategies. Among all plant life‐forms, species with small ranges were restricted to very moist places whereas more widespread species were less dependent on the availability of water. These more common species seem able to tolerate drier conditions, indicated by the minimum rainfall conditions where they are found and the positive correlation with local habitat openness. Light‐demanding endemics were more common and widespread than shade‐tolerant species, and there was a trend towards wind‐dispersed species having a higher proportion of records in open places. This suggests that how widespread and common an endemic species is depends on being able to tolerate open and drier conditions.Main conclusions A ruderal strategy seems to be key for understanding the success of endemics in the Upper Guinean forests, and indicates the important role of disturbances in shaping the composition of these tropical forests. Our results have large implications for predicting the potential effect of increasing drought on rare endemic plant species of West African forests.

AVHRR derived phenological change in the Sahel and Soudan, Africa, 1982–2005

The Sahel region of Africa has experienced a decrease in rainfall from the early 1960s to mid 1990s. Recent studies have detected an increased in NDVI amplitude and growing season integrated NDVI for the region since 1982. However, these studies have not examined how plant phenology has changed. Phenology examines life cycle events such as bud burst and leaf senescence. Using the software TIMESAT to estimate phenological parameters from the GIMMS AVHRR NDVI dataset, we have found significant positive trends for the length of the growing and end of the growing season for the Soudan and Guinean regions, but significant trends in the Sahel could not be detected. The geographical extent of these trends contrasts with the more northern extent of positive trends of NDVI amplitude and growing season integrated NDVI. Results suggest two types of “greening” trends associated with rainfall change since the drought in the early 1980s.

Tropical Rainfall Measuring Mission observation and regional model study of precipitation diurnal cycle in the New Guinean region

The diurnal cycle of precipitation in the New Guinean region is studied on the basis of satellite observations from Tropical Rainfall Measuring Mission (TRMM) Precipitation Radar (PR) measurements and regional atmospheric model simulations. The study focuses on the effects of both the land‐sea breeze and the orographic forcing on the diurnal evolution of precipitation during the rainy season (January–March) in the region. The 7‐year TRMM PR data composite reveals several distinct features of the precipitation diurnal cycle in the region. Precipitation bands develop in the inland coastal region in the late morning to early afternoon and migrate inland from both northeast and southwest sides of the New Guinean Island following the inland penetration of the sea‐breeze fronts. A separate convective rainband develops over the central mountain ridge in the early afternoon as a result of the development of the upslope winds due to the elevated surface warming over the mountain in the morning hours. This mountain ridge rainband intensifies and becomes the dominant rainband as the coastal rainbands associated with the sea‐breeze fronts weaken during the late afternoon and the early evening. In the midnight to the early morning the rainband over the mountaintop weakens as downslope winds develop and splits into two rainbands, propagating away from the mountain ridge, one to the north and one to the south, and weakens over the lowland some distance away from the coasts. Meanwhile a coastal rainband develops offshore on each side of the island in the late evening to midnight and remains strong through early morning before it migrates offshore. As a result, the rainfall rate peaks in the late afternoon to early evening in most land areas except for in the lowland regions between the coastlines and the mountain where the rainfall rate peaks during the midnight, while the rainfall rate peaks in the late evening to early morning in most coastal regions offshore. The distribution of the diurnal amplitude shows two maxima: one over the mountains and the other in the coastal regions offshore. Convective rainfall rate peaks in the late afternoon while stratiform rainfall rate peaks in the midnight to early morning. The latter dominates the large diurnal amplitude over the mountain areas in the early morning. The above broad features are simulated reasonably well in a control experiment with a high‐resolution regional atmospheric model. A sensitivity experiment with the terrain removed is conducted to elucidate the role of orographic forcing in the diurnal evolution of both the local circulation and rainfall patterns. The results show that the orographic forcing affects the diurnal precipitation through three major processes. First, the orography increases the moisture convergence at low levels by blocking and deflecting the mean flow. Second, the upslope winds help initiate convection in the afternoon at the mountaintop. Finally, the deep convection over the mountain acts as a source of propagating gravity waves, which help initiate rainbands in the coastal regions offshore in the late evening to early morning. Implication of the results is discussed.

Revision of the subgenus Marquesania (Acari : Atopomelidae : Listrophoroides)

The subgenus Marquesania Womersley (Acari : Atopomelidae : Listrophoroides) is revised. The species of this subgenus are permanent parasites living in the fur of rats (Rodentia : Murinae) in the Oriental region, Australia and New Guinea. Most of the type material has been examined. Two new species, Listrophoroides melomys, sp. nov. from Melomys moncktoni (Thomas) and L. mordax, sp. nov. from Rattus mordax (Thomas) are described from New Guinea. A new diagnosis of the subgenus Marquesania, detailed descriptions, and a key for all species is provided. The phylogenetic reconstruction of the subgenus Marquesania was effected by the method of parsimonius cladistics. The monophyly of the subgenus is strongly supported by this analysis, and most species from the Oriental region fall at the base of the cladogram. The distribution of Marquesania species on their hosts is discussed. It is suggested that these mites originated in the Oriental region and then migrated to Australia and New Guinea. The distribution of Marquesania species in the Australian and New Guinean regions is noticeably complicated, reflecting the complex settling history of their hosts.

The Composition and Spatial Structure of Coastal Fish Communities in Western Africa (Guinean Region)

The Composition and Spatial Structure of Coastal Fish Communities in Western Africa (Guinean Region)

GLOBAL, REGIONAL, AND LOCAL PATTERNS IN SPECIES RICHNESS AND ABUNDANCE OF BUTTERFLYFISHES

Butterflyfish communities vary in richness longitudinally from highs of >30 species to lows of 2–3 species. We investigated this gradient because it provides an opportunity to address some basic questions relating to determinants of community structure, e.g., are richness and abundance functions of geography or of local conditions? How are richness and density of species populations related? Do community-level processes, such as competition, determine community structure? In a broader sense, to what extent are community properties internally deterministic as opposed to being functions of higher-level processes? From 1981 through 1997 we counted kinds and number of butterflyfishes on over 2000 10-min transects distributed from the eastern Caribbean to the western Indian Ocean and Red Sea. We grouped transects at the same site into stations, stations in the same local area into islands, and islands into 18 geographic regions, thus organizing the data into four spatial levels. For each station, extent of live coral cover and degree of open-ocean influence were estimated. Richness is highest in the Philippine–Bornean–New Guinean region and declines radially from that center. Total number of individual butterflyfish also declines over that gradient. On more local scales, increased open-ocean exposure and live-coral cover enhance both richness and numerical abundance. Because species richness declines more rapidly with distance from the richness center than does abundance, across the same gradient average abundance per benthivore species rises. In peripheral, species-poor reaches of the Indopacific, the Eastern Tropical Pacific, and the Caribbean the communities are dominated by one or a few very common species. Butterflyfishes respond to changing richness of their communities by adjusting the abundance of individual species. Use of space by individual species decreases with increasing richness. Global richness is determined chiefly by geography; within local areas local factors are more important. Community structure is predominantly organized by richness, hence first by geography and then by habitat characteristics.

Global, Regional, and Local Patterns in Species Richness and Abundance of Butterflyfishes

Butterflyfish communities vary in richness longitudinally from highs of >30 species to lows of 2–3 species. We investigated this gradient because it provides an opportunity to address some basic questions relating to determinants of community structure, e.g., are richness and abundance functions of geography or of local conditions? How are richness and density of species populations related? Do community-level processes, such as competition, determine community structure? In a broader sense, to what extent are community properties internally deterministic as opposed to being functions of higher-level processes? From 1981 through 1997 we counted kinds and number of butterflyfishes on over 2000 10-min transects distributed from the eastern Caribbean to the western Indian Ocean and Red Sea. We grouped transects at the same site into stations, stations in the same local area into islands, and islands into 18 geographic regions, thus organizing the data into four spatial levels. For each station, extent of live coral cover and degree of open-ocean influence were estimated. Richness is highest in the Philippine–Bornean–New Guinean region and declines radially from that center. Total number of individual butterflyfish also declines over that gradient. On more local scales, increased open-ocean exposure and live-coral cover enhance both richness and numerical abundance. Because species richness declines more rapidly with distance from the richness center than does abundance, across the same gradient average abundance per benthivore species rises. In peripheral, species-poor reaches of the Indopacific, the Eastern Tropical Pacific, and the Caribbean the communities are dominated by one or a few very common species. Butterflyfishes respond to changing richness of their communities by adjusting the abundance of individual species. Use of space by individual species decreases with increasing richness. Global richness is determined chiefly by geography; within local areas local factors are more important. Community structure is predominantly organized by richness, hence first by geography and then by habitat characteristics.

West African Monsoon Dynamics and Eastern Equatorial Atlantic and Pacific SST Anomalies (1970-88)

Abstract The Laboratoire de Meteorologie Dynamique atmospheric GCM is used to investigate relationships between West African monsoon dynamics and SST anomalies in the eastern equatorial Atlantic and Pacific for the period 1970–88. Positive SST anomalies in the eastern equatorial Pacific, mainly associated with a larger east–west divergent circulation over the tropical Atlantic, are found to coincide with negative rainfall anomalies over West Africa. This is the case for the composite ENSO warm episodes of 1972, 1976, 1982, and 1983. By contrast, positive SST anomalies in the eastern equatorial Atlantic are accompanied by a southward shift of the intertropical convergence zone along with negative rainfall anomalies in the Sahel and positive rainfall anomalies in the Guinean region. This was the case in 1987. The ENSO warm event during this year had apparently no significant impact on West African monsoon dynamics. A zonal atmospheric coupling associated with differences of SST anomalies between the eastern...

West African Monsoon Dynamics and Eastern Equatorial Atlantic and Pacific SST Anomalies (1970–88)

Abstract The Laboratoire de Météorologie Dynamique atmospheric GCM is used to investigate relationships between West African monsoon dynamics and SST anomalies in the eastern equatorial Atlantic and Pacific for the period 1970–88. Positive SST anomalies in the eastern equatorial Pacific, mainly associated with a larger east–west divergent circulation over the tropical Atlantic, are found to coincide with negative rainfall anomalies over West Africa. This is the case for the composite ENSO warm episodes of 1972, 1976, 1982, and 1983. By contrast, positive SST anomalies in the eastern equatorial Atlantic are accompanied by a southward shift of the intertropical convergence zone along with negative rainfall anomalies in the Sahel and positive rainfall anomalies in the Guinean region. This was the case in 1987. The ENSO warm event during this year had apparently no significant impact on West African monsoon dynamics. A zonal atmospheric coupling associated with differences of SST anomalies between the eastern equatorial Pacific and the Atlantic is evident in the period 1970–88. Positive (negative) phases of this coupling could enhance the impact of ENSO warm (cold) events on West African monsoon dynamics.

Sea Surface Temperature Fields Associated with West African Rainfall Anomaly Types

Four West African rainfall anomaly types are defined in relation to the northern summer rainfall departure signs in the Sahel and in the Guinean region in order to investigate the statistical links between interannual variability of West African rainfall and sea surface temperature (SST) through the period 1950–90. Composite analysis depicts the setup of four different mean SST anomaly fields. Drought over all of West Africa is associated with the growth of positive SST anomalies in the eastern Pacific and in the Indian Ocean, and negative SST anomalies in the northern Atlantic and in the Gulf of Guinea. In contrast, drought limited to the Sahel corresponds mostly to a northward expansion of positive SST anomalies in the southern Atlantic, and negative SST anomalies in the northern Atlantic. Northward expansion of negative SST anomalies in the southern Atlantic, positive SST departures in the northern Atlantic, and development of negative SST anomalies in the eastern Pacific appear to be synchronous of flood limited to the Sahel. Flooding over all of West Africa is mainly associated with positive SST anomalies in the northern Atlantic. This approach complements previous papers dealing with rainfall anomalies located in the Sahel alone. In particular, it points out different associations between Atlantic/Pacific SST anomalies and Sahel rainfall variability. Individual cases are also discussed, especially the case of 1972 when a West African rainfall deficit was concomitant to a southward location of the intertropical convergence zone over the tropical Atlantic.

Freshwater fish zoogeography in west Africa: faunal similarities between river basins

Similarities between the freshwater fish faunas of 52 west African rivers have been investigated and three main zoogeographic regions recognized. The Sudanian region includes all rivers from Senegal to the Omo, as well as coastal basins from Ivory Coast to the Cross and the Wouri. The Upper Guinean region comprises the coastal basins from Guinea to Liberia and the Lower Guinean one, the coastal rivers of Cameroon and Gaboon. The Sudanian region can be sub-divided into a Sudanian region sensu stricto, including the Sahelo-Sudanese rivers, and the Eburneo-Ghanean region corresponding to coastal basins from the Cess (or Nipoue, Ivory Coast) to the Pra (Ghana). These delimitations give an highly significant within region faunal homogeneity, even if the effect of geographical proximity between rivers is removed. 21 to 71% of the fish species in each region are endemics. The present patterns of distribution are the result of past climatic and geological events affecting west Africa and, given this framework, the role of alternating wet and dry periods during the early Quarternary is emphasized as well as the importance of mountains as dispersal barriers. Role of recent river connections and links via lagoon is emphasized in explaining river faunal similarities within biogeographical regions.

Guineapsaltria, a new genus from the Australian — New Guinean region (Homoptera, Tibicinidae), with notes on its taxonomy and biogeography

The genus Guineapsaltria is erected for eight species, distributed in New Guinea and northeastern Queensland. Five species are transferred from the genus Baeturia Stål, 1866 and redescribed, viz. G. chinai (Blöte, 1960), G. flava (Goding & Froggatt, 1904), G. pallida (Blöte, 1960),G. stylata (Blöte, 1960), and G. viridula (Blöte, 1960), while three species are described as new to science (G. flaveola n. sp., G. pallidula n. sp., and G. pennyi n. sp.). G. flava is designated as the type species of the genus. Baeturia minuta Blöte, 1960 is synonymized with Guineapsaltria flava. The phylogeny of Guineapsaltria is discussed and some remarks are made on its phylogeneticrelationships with other New Guinean and Australian tibicinid genera. A key to the males and maps of distribution are presented.

Flocks of Brown and Black New Guinean Birds: A Bicoloured Mixed-species Foraging Association

A type of itinerant mixed-species foraging association of New Guinean birds, the brown and black flock, is distinctive in that member species converge on two alternative colours rather than on one, and in that the flock retains its character through many geographic and altitudinal changes of species composition. To complement Bell's intensive study of a single lowland flock, I survey the flocks throughout their geographic and altitudinal range. The flocks are composed of 35 species belonging to 7 families and are led hierarchically: by the Rufous Babbler Pomatostomus kidorei if it is present, otherwise by the Rusty Pitohui Pitohui fermgineus if it is present, otherwise by one of four other Pitohui species. The followers include either of two drongo species, 15 bird-of-paradise species, seven cuckoo-shrike species, and five other species. Flock-joining species are all medium to large forest passerines coloured predominantly brown or black. In nine species the male is black, the female brown. Most member species are endemic to the New Guinean region, eat both fruit and insects, and can forage from the understorey to lower canopy. Different flock members may derive different benefits from joining the flocks, including access to food flushed by other species, opportunities for kleptoparasitism, protection from predators, overwhelming of temtorial defenders, and increased foraging efficiency. The possible benefits of convergence in colour include enhancing the confusion of predators, maintaining spacing of allospecific individuals, and promoting flock cohesion through economy of signal. I hypothesize that a flock forms when a noisy social species ('leader' species) provides a critical level of vocal and visual signals that attract other, ecologically and visually similar species ('follower' species).