Cape Verde Islands Research Articles

New records of two deep-sea Periclimenes species (Decapoda, Caridea, Palaemonidae) from the North-East Atlantic

Abstract During the “Tydeman” CANCAP VII expedition to the Cape Verde Islands in 1986 and the “Tyro” MAURITANIA II Expedition to the Banque d’Arguin off the coast of Mauritania in 1988, several specimens belonging to two species within the genus Periclimenes were trawled from deep water constituting range extensions for both species. The specimens are here compared with previous descriptions, illustrated, and their distribution is discussed.

A Comparative Genetic Analysis of Phoenix atlantica in Cape Verde.

The Cape Verde palm tree, Phoenix atlantica, holds significant ecological and cultural importance within the Cape Verde archipelago. However, its genetic distinctiveness has been questioned due to its close relationship and morphological similarity to the date palm (Phoenix dactylifera). In this study, we used an expanded sample set, 18 simple sequence repeat (SSR) markers, and a plastid minisatellite to characterize P. atlantica in Cape Verde and investigate its relationship with other Phoenix species. Our findings identify genetic markers that differentiate the P. atlantica genetic pool, including a unique fixed allele. We also provide evidence of the recent divergence of P. atlantica from Northern African date palm populations, suggesting a relatively recent colonization of Cape Verde by palm trees. Additionally, we characterized the genetic composition of palm tree populations across three Cape Verde islands, concluding that wild samples from certain populations in Boavista and Sal are best suited for establishing a seed and/or germplasm bank for replantation efforts, representing a crucial step for the conservation of Cape Verde's natural heritage. Overall, our results enhance the understanding of the historical trajectories and genetic characterization of palm trees in Africa, offering valuable insights for conservation strategies.

Endless forms most frustrating: disentangling species boundaries in the Ramalina decipiens group (Lecanoromycetes, Ascomycota), with the description of six new species and a key to the group.

Oceanic islands have been recognized as natural laboratories in which to study a great variety of evolutionary processes. One such process is evolutionary radiations, the diversification of a single ancestor into a number of species that inhabit different environments and differ in the traits that allow them to exploit those environments. The factors that drive evolutionary radiations have been studied for decades in charismatic organisms such as birds or lizards, but are lacking in lichen-forming fungi, despite recent reports of some lineages showing diversification patterns congruent with radiation. Here we propose the Ramalina decipiens group as a model system in which to carry out such studies. This group is currently thought to be comprised of five saxicolous species, all of them endemic to the Macaronesian region (the Azores, Madeira, Selvagens, Canary and Cape Verde islands). Three species are single-island endemics (a rare geographic distribution pattern in lichens), whereas two are widespread and show extreme morphological variation. The latter are suspected to harbor unrecognized species-level lineages. In order to use the Ramalina decipiens group as a model system it is necessary to resolve the group's phylogeny and to clarify its species boundaries. In this study we attempt to do so following an integrative taxonomy approach. We constructed a phylogenetic tree based on six molecular markers, four of which are newly developed and generated competing species hypotheses based on molecular (species discovery strategies based on both single locus and multilocus datasets) and phenotypic data (unsupervised clustering algorithms based on morphology, secondary chemistry and geographic origin). We found that taxonomic diversity in the Ramalina decipiens group has been highly underestimated in previous studies. In consequence, we describe six new species, most of them single-island endemics and provide a key to the group. Phylogenetic relationships among species have been reconstructed with almost full support which, coupled with the endemic character of the group, makes it an excellent system for the study of island radiations in lichen-forming fungi. Citation: Blázquez M, Pérez-Vargas I, Garrido-Benavent I, et al. 2024. Endless forms most frustrating: disentangling species boundaries in the Ramalina decipiens group (Lecanoromycetes, Ascomycota), with the description of six new species and a key to the group. Persoonia 52: 44-93. https://doi.org/10.3767/persoonia.2024.52.03 .

“What’s in a name?” Bairdia fasciata Brady, 1870, and two new Caribbean species of Bairdoppilata (Bairdiidae, Podocopida, Ostracoda)

The single specimen of Bairdia fasciata Brady, 1870 in the Great North Museum, Newcastle upon Tyne, UK, is declared to be the holotype by monotypy. Because it is a closed carapace, the internal characters remain unknown. Taxonomically, neither the genus nor the species is identifiable, nor can the subsequent identification in Belize be confirmed. New sampling at the type locality in the Cape Verde Islands is recommended, to recover a population for taxonomic re-description. Here, two new species of Genus Bairdoppilata are described from the carbonate platform of Belize, Ba. magnafasciata, n. sp. and Ba. parvafasciata, n. sp. Both display similarities to B. fasciata from the Cape Verde Islands, but neither one can be identified with that species. Both species are widely distributed in shallow coastal assemblages around the central and northern Caribbean. In taxonomy, names matter, and the correction of published misidentifications is essential. Clarification of these species enables more accurate delineation of ecological and biogeographical distributions in Caribbean assemblages.

A taxonomic revision of the sponge-associated genus Thoracactis Gravier, 1918 (Anthozoa: Zoantharia) based on an integrated approach

Abstract The integrated approach of molecular phylogenetic and morphological analyses has revolutionized the systematics and our understanding of the evolutionary relationships of marine taxa. One such group is the hexacorallian order Zoantharia Rafinesque, 1815. The monotypic genus Thoracactis Gravier, 1918 has been little investigated since its placement within the order Zoantharia more than 100 years ago. Here, we examined museum specimens collected from the Cape Verde Islands (eastern Atlantic) and newly collected specimens from Brazil (southwestern Atlantic), using a combined molecular and morphological approach. Our results conclusively show Thoracactis to be referable to the family Parazoanthidae. Morphological data show that Thoracactis topsenti Gravier, 1918, the type species of this monotypic genus, has a cyclically transitional arrangement of its sphincter muscle, and this arrangement has previously been reported from the Parazoanthidae. Thoracactis can be distinguished from other hexasterophoran glass-sponge-associated genera (Churabana Kise, Montenegro & Reimer, 2022, Parachurabana Kise, 2023, and Vitrumanthus Kise, Montenegro & Reimer, 2022) by a combination of morphological, ecological and molecular phylogenetic data. In addition, molecular phylogenetic analyses clearly indicate that Thoracactis topsenti is placed within Parazoanthidae. These results are yet another demonstration of the utility of comprehensive combined approaches. From now, research attention should focus on the revision of remaining taxonomic questions within the family Epizoanthidae, with the goal of a comprehensively revised suborder Macrocnemina within reach.

On the existence, uniqueness, stability, and numerical aspects for a novel mathematical model of HIV/AIDS transmission by a fractal fractional order derivative

In this study, we explore a mathematical model of the transmission of HIV/AIDS. The model incorporates a fractal fractional order derivative with a power-law type kernel. We prove the existence and uniqueness of a solution for the model and establish the stability conditions by employing Banach’s contraction principle and a generalized α-ψ-Geraghty type contraction. We perform stability analysis based on the Ulam–Hyers concept. To calculate the approximate solution, we utilize Gegenbauer polynomials via the spectral collocation method. The presented model includes two fractal and fractional order derivatives. The influence of the fractional and fractal derivatives on the outbreak of HIV is investigated by utilizing real data from the Cape Verde Islands in 1987–2014.

First documented movement of a humpback whale between the Cape Verde Islands and West Greenland.

The endangered population of humpback whales (Megaptera novaeangliae) breeding and calving off the Cape Verde Islands (CVI) are known to migrate to feeding areas located along the eastern margin of the North Atlantic Ocean (Iceland, and Norway). Here, we report for the first time a confirmed migration of an individual humpback whale from CVI breeding ground to a western North Atlantic feeding ground of West Greenland. This individual humpback, which was photographed and identified off the coast of West Greenland in 2021, was previously documented in CVI 22 years before (1999). An annual subsistence hunt for humpbacks occurs in West Greenland and the resighting at this location with a humpback whale from CVI has strong implications for the conservation efforts of the small CVI population.

Mineral Chemistry of Olivine, Oxy-Spinel, and Clinopyroxene in Lavas and Xenoliths from the Canary, Azores, and Cape Verde Islands (Macaronesia, North Atlantic Ocean): New Data and Comparisons with the Literature

An electron microprobe study was carried out on olivine, clinopyroxene, and oxy-spinel occurring in basalts and dunite xenoliths from the archipelagos of the Azores, the Canary Islands, and Cape Verde. By comparing our results with previously published data from the volcanic islands of Macaronesia, we confirmed the validity of the compositions of olivine, clinopyroxene, and oxy-spinel as geochemical tracers. The origin of olivine, i.e., crystallized in the lithospheric mantle or in volcanic rocks, was successfully discriminated. Olivine from Lanzarote dunite xenoliths, which represent fragments of the mantle transported to the surface by host magmas, exhibited higher Fo% values (Fo91.02 to Fo91.94) and a different distribution of minor elements Ca, Ni, and Mn (CaO up to 0.42 wt%, NiO 0.07–0.41 wt%, MnO 0.06–0.3 wt%) when compared with olivine occurring as phenocrysts in basaltic lavas from the Macaronesian islands. The highly variable forsterite contents (Fo75.1 to Fo94.4) in olivine from gabbro and peridotite xenoliths found across the islands of Macaronesia were attributed to fractional crystallization that started in a deep magma reservoir, suggesting that these xenoliths represent cumulate rocks and not mantle fragments. Alternatively, these xenoliths may have been affected by the interaction with metasomatic fluids. The composition of clinopyroxene phenocrysts was used to decipher formation conditions under extensional tectonics. Their composition suggests that the host lavas have an alkaline to calc-alkaline signature. Furthermore, clinopyroxene euhedral shapes and compositions suggest an origin by fractional crystallization in a closed magmatic system. The composition alone of oxy-spinel from Macaronesian basalts and xenoliths was not sufficient to draw conclusions about the geodynamic environment where they were formed. Nevertheless, the relationship between oxy-spinel and olivine crystallized in equilibrium was successfully used as oxybarometers and geothermometers. The oxy-spinel–olivine pairs show evidence that the basaltic lavas were crystallized from melts with higher oxygen fugacity and different cooling histories than those of the mantle xenoliths, as the latter crystallized and re-equilibrated much slower than the basalts.

Compositional variations in shield-stage volcanism in Fogo, Cape Verde islands

The intraplate oceanic island of Fogo (Cape Verde islands) is in the shield-stage of its evolution. It experienced a major lateral collapse ca. 70 ka ago, after which a sequence of lavas about 2 km thick infilled the collapse scar, with eruptions continuing to the present day. Nearly 100 lavas from before and after the collapse have been sampled and analysed for bulk rock compositions. These lavas have been divided into five Formations (2 pre-collapse and 3 post-collapse), using stratigraphic principles. There is little difference in the major and trace element compositions of pre- and post-collapse lavas, and the main process that gives rise to their diversity is fractional crystallization of observed mineral phases. Pre-collapse lavas show a narrower range of bulk compositions than the post-collapse lavas, but this may be because the sampling strategy avoided these more altered and poorly exposed lavas. A group of high-P2O5 lavas, erupted both before and after the collapse, may have been extensively contaminated by local seamount-stage intrusive carbonatites. A subset of 30 samples was analysed for Sr, Nd and Pb isotope ratios. They show a plume component which has interacted with two contaminants: (1) an increase in 87Sr/86Sr and decrease in 143Nd/144Nd with decreasing MgO, which indicates varying amounts of assimilation of an enriched lithospheric component coupled to fractionation (AFC), and (2) contamination of the more fractionated magmas, without further fractionation, involving the suspected carbonatite contaminant which originates from a more isotopically depleted source. Overall trends of increasing 87Sr/86Sr, and slight decreases in 143Nd/144Nd and all radiogenic Pb isotope ratios, with decreasing age of eruption, indicate a general increase in the assimilated lithospheric component throughout shield-stage activity. However, there is no clear evidence of any change in isotope compositions across the period of the collapse. All Formations show similar wide and overlapping ranges of isotope compositions, regardless of the timescales represented by each Formation. This implies that much short-term variation in the magma sources was superimposed on the overall trend of increasing lithospheric assimilation.

Vertical distribution of epibenthic megafauna of a large seamount west of Cape Verde islands (tropical North Atlantic)

Seamounts are thought to function as hotspots of megafauna diversity due to their topology and environmental characteristics. However, assessments of megafauna communities inhabiting seamounts, including diversity and density, are scarce. In this study, we provide megafauna diversity and density estimates for a recently discovered, not yet characterized seamount region (Boetius seamounts) west of Cape Verde (N17° 16′, W29° 26′). We investigated the distribution of epibenthic megafauna over a large depth gradient from the seamount’s summit at 1400 m down to 3200 m water depth and provided qualitative and quantitative analyses based on quantified video data. In utilizing an ocean floor observation system (OFOS), calibrated videos were taken as a horizontal transect from the north-eastern flank of the seamount, differentiating between an upper, coral-rich region (−1354/−2358 m) and a deeper, sponge-rich region (−2358/−3218 m). Taxa were morphologically distinguished, and their diversity and densities were estimated and related to substrate types. Both the upper and deeper seamount region hosted unique communities with significantly higher megafauna richness at the seamount’s summit. Megafauna densities differed significantly between the upper (0.297 ± 0.167 Ind./m2) and deeper community (0.112 ± 0.114 Ind./m). The seamount showed a vertical zonation with dense aggregations of deep-sea corals dominating the seamount’s upper region and colonies of the glass sponges Poliopogon amadou dominating the deeper region. The results are discussed in light of detected substrate preferences and co-occurrence of species and are compared with findings from other Atlantic seamounts.

Natural variation of temperature acclimation of Arabidopsis thaliana.

Acclimation is a multigenic trait by which plants adjust photosynthesis and metabolism to cope with a changing environment. Here, natural variations of photosynthetic efficiency and acclimation of the central carbohydrate metabolism were analyzed in response to low and elevated temperatures. For this, 18 natural accessions of Arabidopsis thaliana, originating from Cape Verde Islands and Europe, were grown at 22°C before being exposed to 4°C and 34°C for cold and heat acclimation, respectively. Absolute amounts of carbohydrates were quantified together with their subcellular distribution across plastids, cytosol and vacuole. Linear electron transport rates (ETRs) were determined together with the maximum quantum efficiency of photosystem II (Fv/Fm) for all growth conditions and under temperature fluctuation. Under elevated temperature, ETR residuals under increasing photosynthetic photon flux densities significantly correlated with the degree of temperature fluctuation at the original habitat of accessions, indicating a geographical east/west gradient of photosynthetic acclimation capacities. Plastidial sucrose concentrations positively correlated with maximal ETRs under fluctuating temperature, indicating a stabilizing role within the chloroplast. Our findings revealed specific subcellular carbohydrate distributions that contribute differentially to the photosynthetic efficiency of natural Arabidopsis thaliana accessions across a longitudinal gradient. This sheds light on the relevance of subcellular metabolic regulation for photosynthetic performance in a fluctuating environment and supports the physiological interpretation of naturally occurring genetic variation of temperature tolerance and acclimation.

Water quality for agricultural irrigation produced by two municipal sewage treatment plants in Santiago Island-Cape Verde: Assessment of chemical parameters and pharmaceutical residues

Abstract Cape Verde, a West Africa Island country, is exposed to climate change effect. An effective way of reducing its poverty and achieving food security is to provide its agricultural sector with water. The purpose of this study is to monitor treated water quality to ensure that any pollutants are below the limits set to ensure the safety and sustainability of reuse because only 10% of its treated wastewater is reused. For the first time on Cape Verde islands, besides chemical quality, the occurrence of 11 pharmaceutical compounds (PhC) in the influent and effluent of two natural wastewater treatment plants (WWTPs) was monitored to assess the effectiveness of the treatment technologies and removal efficiencies of these pollutants. Of the 11 target PhC, nine were detected in influent samples within the ng·L−1 to μg·L−1 range. Lower concentrations were detected in one WWTP vs. the other. Nevertheless, the removal efficiencies for most compounds were similar in both WWTPs: within the ranges of 82–92% for beta-blockers, 48–99% for stimulants and 44–95% for nonsteroidal anti-inflammatories, while carbamazepine (anticonvulsant) concentrations increased in effluents. WWTPs produce water that meets water quality standards for irrigation if a properly designed and managed reusing system is adopted.

Genetic Architecture of Flowering Time Differs Between Populations With Contrasting Demographic and Selective Histories.

Understanding the evolutionary factors that impact the genetic architecture of traits is a central goal of evolutionary genetics. Here, we investigate how quantitative trait variation accumulated over time in populations that colonized a novel environment. We compare the genetic architecture of flowering time in Arabidopsis populations from the drought-prone Cape Verde Islands and their closest outgroup population from North Africa. We find that trait polygenicity is severely reduced in the island populations compared to the continental North African population. Further, trait architectures and reconstructed allelic histories best fit a model of strong directional selection in the islands in accord with a Fisher-Orr adaptive walk. Consistent with this, we find that large-effect variants that disrupt major flowering time genes (FRI and FLC) arose first, followed by smaller effect variants, including ATX2 L125F, which is associated with a 4-day reduction in flowering time. The most recently arising flowering time-associated loci are not known to be directly involved in flowering time, consistent with an omnigenic signature developing as the population approaches its trait optimum. Surprisingly, we find no effect in the natural population of EDI-Cvi-0 (CRY2 V367M), an allele for which an effect was previously validated by introgression into a Eurasian line. Instead, our results suggest the previously observed effect of the EDI-Cvi-0 allele on flowering time likely depends on genetic background, due to an epistatic interaction. Altogether, our results provide an empirical example of the effects demographic history and selection has on trait architecture.

Dissolved Organic Matter Fluorescence as a Tracer of Upwelling and Microbial Activities in Two Cyclonic Eddies in the Eastern Tropical North Atlantic

AbstractMesoscale eddies are frequently observed in the Eastern Tropical North Atlantic (ETNA), yet their effects on the transport and distribution of biogeochemical solutes, and specifically on the production and remineralization of dissolved organic matter (DOM) remain difficult to elucidate. Here, we investigated the submesoscale variability of chromophoric DOM (CDOM) and fluorescent DOM (FDOM) together with microbial production and remineralization processes in two cyclonic eddies (CEs) in the ETNA during summer and winter 2019. One CE, formed near the coast off Mauritania during the post‐upwelling season, was sampled along a ∼900 km zonal corridor between Mauritania and the Cape Verde Islands. The other CE, formed nearby Brava Island, was out of coastal influence. Four fluorescent components were identified with parallel factor analysis, two humic‐like, and two protein‐like components. Humic‐like FDOM components correlated to optode‐based community respiration and were also good indicators of upwelling associated with the Brava Island CE as they correlated to physical parameters (e.g., temperature) and to dissolved inorganic nitrogen. The tryptophan‐like FDOM components correlated with the carbon and nitrogen content of semi‐labile DOM, phytoplankton biomass, community respiration, and bacterial production. Overall, our study revealed that DOM optical properties are suitable for tracing freshly produced organic matter and the transport of remineralized DOM within offshore eddies.

“Travel on the Highways of the Broad Atlantic”: Toward a Brief History of the Cape Verdean Packet Trade

Abstract Beginning with the purchase of the schooner Nellie May and concluding with the docking of the schooner Ernestina in the Port of New Bedford, Cape Verdeans in southeastern New England and on the Cape Verde islands off the West African coast purchased and refurbished old, decommissioned ships from New Bedford's bygone whaling and fishing era. Between 1892 and 1965, this fleet of ships, named the Cape Verdean Packet Trade, specialized in the transportation of goods, people, and news between the United States and the Cape Verde islands. The packet trade was a large-scale effort that transformed the Atlantic into a highway for Cape Verdean trade, communication, emigration, and family reunification. Cape Verdeans’ radical repurposing of the packet vessels converted the Atlantic Ocean from a site of dispossession, enslavement, and immobility to a reimagined zone of possibility and freedom through mobility for African-descended peoples. These Cape Verdean–owned and operated packets assisted Cape Verdean Americans in maintaining long-term connections to loved ones separated by the Atlantic. In this way, the Cape Verdean Packet Trade's more than 1,200 voyages connected the United States to Cape Verde as part of a transnational social field and single economic universe for more than seventy years.

Increase in Cape Verde hurricanes during Atlantic Niño

At seasonal-to-interannual timescales, Atlantic hurricane activity is greatly modulated by El Niño–Southern Oscillation and the Atlantic Meridional Mode. However, those climate modes develop predominantly in boreal winter or spring and are weaker during the Atlantic hurricane season (June–November). The leading mode of tropical Atlantic sea surface temperature (SST) variability during the Atlantic hurricane season is Atlantic Niño/Niña, which is characterized by warm/cold SST anomalies in the eastern equatorial Atlantic. However, the linkage between Atlantic Niño/Niña and hurricane activity has not been examined. Here, we use observations to show that Atlantic Niño, by strengthening the Atlantic inter-tropical convergence zone rainband, enhances African easterly wave activity and low-level cyclonic vorticity across the deep tropical eastern North Atlantic. We show that such conditions increase the likelihood of powerful hurricanes developing in the deep tropics near the Cape Verde islands, elevating the risk of major hurricanes impacting the Caribbean islands and the U.S.

Humpback whale (Megaptera novaeangliae) occurrence near the Cape Verde Islands, based on American 19th century whaling records

American 19th century whalers often passed through the Cape Verde Islands (CVI) during the boreal winter and some of them spent a few weeks or months hunting humpback whales (Megaptera novaeangliae) in the bays and near-shore waters of the archipelago. Logbooks were examined from 26 voyages that involved some humpback whaling at the CVI, and information was obtained from various sources on approximately 77 additional voyages that definitely or probably humpbacked there. Twenty of the logbooks contained 396 records of an estimated 1,105 humpback whale encounters (catches, strikes and sightings). The largest estimated numbers of encounters and most of the whaling activity were around the islands of Sal, São Vicente and São Nicolau (272, 269 and 229 encounters, respectively). The peak month for humpback whale occurrence in the region appears to have been March (160 records of an estimated 465 whale encounters), with many records from February (110 records of 282 encounters) and April (86 records of 258 encounters). Catch data from the logbooks were combined with commercial data on landings of oil and reported vessel positions to estimate numbers of humpback whales taken in the CVI by the American fleet. Results suggest that American whaling for humpback whales was most intensive in the Cape Verdes during the 1850s and 1860s when at least a few hundred and perhaps more than 500 whales were killed in at least 45 and perhaps more than 80 vessel-seasons. In many respects, the Cape Verdes fishery was similar to that in the West Indies, with cows and calves frequently taken and a similar seasonal peak in whale occurrence. A crude analysis of encounter rates suggests that humpback whale density in the CVI was comparable to that in the major West Indies grounds, a situation that is clearly not the case today.

Screening of natural Wolbachia infection in mosquitoes (Diptera: Culicidae) from the Cape Verde islands

BackgroundWolbachia pipientis is an endosymbiont bacterium that induces cytoplasmic incompatibility and inhibits arboviral replication in mosquitoes. This study aimed to assess Wolbachia prevalence and genetic diversity in different mosquito species from Cape Verde.MethodsMosquitoes were collected on six islands of Cape Verde and identified to species using morphological keys and PCR-based assays. Wolbachia was detected by amplifying a fragment of the surface protein gene (wsp). Multilocus sequence typing (MLST) was performed with five housekeeping genes (coxA, gatB, ftsZ, hcpA, and fbpA) and the wsp hypervariable region (HVR) for strain identification. Identification of wPip groups (wPip-I to wPip-V) was performed using PCR–restriction fragment length polymorphism (RFLP) assay on the ankyrin domain gene pk1.ResultsNine mosquito species were collected, including the major vectors Aedes aegypti, Anopheles arabiensis, Culex pipiens sensu stricto, and Culex quinquefasciatus. Wolbachia was only detected in Cx. pipiens s.s. (100% prevalence), Cx. quinquefasciatus (98.3%), Cx. pipiens/quinquefasciatus hybrids (100%), and Culex tigripes (100%). Based on the results of MLST and wsp hypervariable region typing, Wolbachia from the Cx. pipiens complex was assigned to sequence type 9, wPip clade, and supergroup B. PCR/RFLP analysis revealed three wPip groups in Cape Verde, namely wPip-II, wPip-III, and wPip-IV. wPip-IV was the most prevalent, while wPip-II and wPip-III were found only on Maio and Fogo islands. Wolbachia detected in Cx. tigripes belongs to supergroup B, with no attributed MLST profile, indicating a new strain of Wolbachia in this mosquito species.ConclusionsA high prevalence and diversity of Wolbachia was found in species from the Cx. pipiens complex. This diversity may be related to the mosquito's colonization history on the Cape Verde islands. To the best of our knowledge, this is the first study to detect Wolbachia in Cx. tigripes, which may provide an additional opportunity for biocontrol initiatives.Graphical

Local African responses to the early slave trade trade in Upper Guinea, sixteenth to seventeenth centuries

When Portuguese mariners reached the Senegambian coast shortly before 1450, they quickly engaged in taking small numbers of captives back to Lis-bon. In Senegambian societies, varied forms of limited or temporary servile status existed before this first contact, and the interior was connected to the older trans-Saharan slave trade. By the 1580s several thousand Africans a year were being pur-chased and taken either to the Cape Verde Islands, to Europe or, increasingly, to the Americas. Africans responded rapidly but variously to the development of this slave trade. They protected themselves by moving into remote or geographically protect-ed areas; and they learned to defend themselves and to turn the tables by capturing their aggressors. Some, such as the Bijogo, actively entered the slave trade, even cap-turing Portuguese. Finally, several communities of escaped slaves were established, with at least the tacit support of local Africans. These Maroon communities were composed at least partly of captives who had escaped from the Portuguese.

Migration of a humpback whale (Megaptera novaeangliae) between the Cape Verde Islands and Iceland

The movements of individual humpback whales (Megaptera novaeangliae) can be tracked by matching photographs of the distinctive markings on the ventral sides of their tail flukes. During the winter-spring seasons of 1990, 1991, 1995, 1996, 1999, 2000, 2001 and 2002 a total of 42 individual humpbacks were identified by fluke photographs from the waters of the Cape Verde Islands. These were compared with photographs taken elsewhere in the North Atlantic. One match was made with a whale previously photographed in the Denmark Strait off Iceland, providing the first direct evidence of a link between the humpbacks in tropical waters of the eastern North Atlantic and a high-latitude feeding ground. This finding is consistent with the mitochondrial DNA evidence of at least two distinct breeding populations of humpback whales in the North Atlantic. The presence of cows with young calves as well as singers during the humpback mating and calving season implies that waters surrounding the Cape Verde archipelago constitute a breeding and calving ground for an eastern North Atlantic population of humpback whales.