Tornabenea ribeirensis (Apiaceaeb a new species from São Nicolau, Cape Verde Islands (West Africa)

Many species of Apiaceae are found in the Macaronesien Region. Several have been introduccd by human activities, but a number of taxa is endemic to the different archipelagos or even rrstrictcd to a single island. The following enumeration is based mainly on HANSEN & SUNDING ( 1993). In the Arores 28 different taxa of Apiaceae occur; among them four endemic species [AUIMI; hrrrrii WATSON, A. trifoliatum (WATSON) TKEL., Clrtrc~,y~l~~ll~r~~~ cl:oricrm TREL.. SOErich trwrictr GUTIINICK ex SEUB.]. In Madeira the Apiaceae are very diverse and consist ol’ 29 species and subspecies. From the archipelago two monotypic genera, rC/c/trtio. velitru~rr t/ccipicvr.s (SCHRAD. & J. C. WENDL.) Ho~+hl. md kJorli:ia edu[is LOWE and ~hrcc cndcmic species [Oemmrlre diwricore (R. BR.) MABB.. I/nperrr/orio lotvei COSS. and Burrirr~r hre~$~lirrnr LOWE] are described. The Canary Islands have the highest numbcr of plant-species and a high level of endemism. 5-l taxa of Apiaceae are recorded including three endemic genera (Rtrrheopsis A. HANSEX & KUNKEL, Todm-oa PARL. and Tiqyrmm PARL.) and further I5 endemic taxa. The Apiaceae are represented in the Cape Verde Islands by I2 species. Most of the taxa have been introduced by human activities (LOBIN & ZIZKA 1957) like Amvhm grm’eo- 1efr.s L., Apirm grmvolerrs L, Foerricrrhrr urlgore MILL.. Corimrtlru~t~ srrtirvrrrr L. or Petrosilerrm crisprrm (FRILL.) A.W.HILL. These species are cultivated and some of them later became \\esdy. Other species like Ciclosper- UWL /e/~fo/~/l~ll~rrtr (PER%) SPRAGUE (= Apimr leproplr~llrr~rr) are weeds of cultivated grounds or wasted lands. All these species are today widespread in temperate. subtropical or tropical regions all over the world. The only native species are to be found in the endemic genus To~wI~~I~~~ PARL.

Phoenix in the Cape Verde Islands

The African Republic of Cape Verde consists of nine inhabited and several uninhabited volcanic islands set out in the Atlantic Ocean, about 500 km off the most westerly point of the African mainland and 1500 km south of the Canary Islands @g. 2). Most are rugged and mountainous; three (Sal, Maio, and Boavista) are flat, desert islands with sand beaches. Precipitation is meagre and very erratic; indeed Cape Verde can be seen as an island extension of the arid Sahel zone. Three species of the genus Phoenix are recorded from the Cape Verde Islands, P. akzctyli&a L., P. canariensis Chabaud and P. atlantica A. Chev. While the former two species have almost certainly been introduced by man, the latter is said to be endemic to the islands. Perhaps because the Cape Verdes are a particularly isolated set of islands or because palms are notoriously awkward to collect, little is known about the taxonomy, origins and natural history of this species. Phoenix atlantica was described by the French botanist Auguste Chevalier (1935a) following field exploration in the Cape Verdes in 1934 (Chevalier 1934: 1153). Chevalier provided limited diagnostic characters, defining the species as a clustering palm with 2-6 trunks, 5-15 m in height with dark green leaves 2-3 m in length. He considered it to be most similar in form to P. &ctyZzjkra and P. canariensis, possessing characters of both (Chevalier 1935a). Chevalier’s description indicates that Phoenix atlantica can be distinguished easily from P. canariensis by its clustering growth form (P. canariensis always has a single, stout trunk) and its shorter, straighter leaves. However, the differences between P. atlantica and P. dactylzjkra appear much more subtle. For example, while P. dacfylifera is usually observed as single-stemmed, when left undisturbed for a number of years it becomes clustering like the Cape Verde Phoenix, so this character on its own is unreliable. Further alleged distinctions include acuminate (P. atlantica) versus rounded (P. dactylzjkra) petals in the male flowers (Chevalier 1935a, b, Greuter 1967: 249, and Brochmann et al. 1997), fruit 2 cm long (P. atlantica) versus fruit more than 2.5 cm long (P. dactyl&a) (Brochmann et al.

New data on the distribution and conservation status of some angiosperms of the Cape Verde Islands, W Africa

New data on the distributibn and conservation status of some angiosperms of the Cape Verde Islands, W Africa Intensive field work aud analysis of the state of biodiversity ou all islands during the years iYY.3 lo IYYY Icd lo lhc publication ol’several contributions lo the flora and vegelalion of the archipclago of Cabo Verde (Brochniann & al. 1997, Gornes & Vera-Cruz 1993. Gonles & al. I9YSa-h. 1998, Games 1997. Kilian & Leyens 1994, Leyens 1998. Leyens & Lobin 1995, Lobin & al. 1995) as well as to the compilation of the First Red Data List for the Cape Verde Islnuds (Lcyrus & Lobin 1996). the elaboration of the National Strategy for Biodiversity Conservation (SIPA 19YY) and ! compilation of all areas in urgent need of protection (Leyens unpubl. diplonla thc.\is IYYJ. Gwnes & al. iu prep.). As part UC the activities of the lnstituto National de Invcstig;u$o c Dcscnvolvitucnto Agriirio (INIDA) and the Dcpurtamcnto de GeociSncias do Institute Supcriot de Educ;u$o t ISE) iutcnsive t’icld studies were conducted PI many diffcrctu localilics OII xcvcr;~I islands. resulting in a thesis tGo~nes IY97) and several terminal study papers (Luz IYYY. Cosi;t 1994. Gonsalvez 1999). The results show that the vegetation and flora of the islands arc still IWI fully known and much more field work is needed. hllhot~gh Sanliiqw is one of lhc islands whcrc lhc firs1 holanicill iIlVcxligilliollx wcrr c:crriul WI (Wcbh 1x49. Schruidt 1x52. Chcvalicr IY35) and where uu~ny intensive field studirs wcrc

Multiscale phylogeography: glacial history and autopolyploidy of Biscutella laevigata L. (Brassicaceae) in the Western Alps

Résumé Les changements climatiques du Quaternaire ont eu une influence majeure sur la distribution et l'évolution des biota septentrionaux. Les Alpes offrent un cadre spatio-temporel bien étudié pour comprendre la réactivité de la flore et le potentiel d'adaptation d'une espèce végétale face aux changements climatiques. Certaines hypothèses postulent une diversification des espèces en raison de la disparition complète de la flore des Alpes et d'un isolement important des espèces dans des refuges méridionaux durant les dernières glaciations (Tabula Rasa). Une autre hypothèse stipule le maintien de poches de résistance pour la végétation au coeur des Alpes (Nunataks). Comme de nombreuses espèces végétales présentant un grand succès écologique semblent avoir réagi aux glaciations par la multiplication de leur génome (autopolyploïdie), leur étude en milieu naturel devrait permettre de comprendre les avantages inhérents à la polyploïdie. Biscutella laevigata est un modèle emblématique de biogéographie historique, diverses études ayant montré que des populations diploïdes sont actuellement isolées dans les zones restées déglacées durant le dernier maximum glaciaire, alors que des tétraploïdes ont recolonisé l'ensemble des zones alpines mises à nu par le retrait des glaciers. Si le contexte périglaciaire semble avoir favorisé ce jeune complexe autopolyploïde, les circonstances et les avantages de cette mutation génomique ne sont pas encore clairs. Y a-t-il eu de multiples événements de polyploïdisation ? Dans quelle mesure affecte(nt)il(s) la diversité génétique et le potentiel évolutif des polyploïdes ? Les polyploïdes ont-ils une grande flexibilité génomique, favorisant une radiation adaptative, ou doivent-ils leur succès à une grande plasticité écologique ? Cette étude aborde ces questions à différentes échelles spatiales et temporelles. L'échelle régionale des Alpes occidentales permet d'aborder les facteurs distaux (aspects historiques), alors que l'échelle locale cherche à appréhender les facteurs proximaux (mécanismes évolutifs). Dans les Alpes occidentales, des populations ont été densément échantillonnées et étudiées grâce à (1) leur cytotype, (2) leur appartenance taxonomique, (3) leur habitat et (4) des marqueurs moléculaires de l'ADN chloroplastique, en vue d'établir leurs affinités évolutives. Á l'échelle locale, deux systèmes de population ont été étudiés : l'un où les populations persistent en périphérie de l'aire de distribution et l'autre au niveau du front actif de colonisation, en marge altitudinale. Les résultats à l'échelle des Alpes occidentales révèlent les sites d'intérêt (refuges glaciaires, principales barrières et voies de recolonisation) pour une espèce représentative des pelouses alpines, ainsi que pour la biodiversité régionale. Les Préalpes ont joué un rôle important dans le maintien de populations à proximité immédiate des Alpes centrales et dans l'évolution du taxon, voire de la végétation. Il est aussi démontré que l'époque glaciaire a favorisé l'autopolyploïdie polytopique et la recolonisation des Alpes occidentales par des lignées distinctes qui s'hybrident au centre des Alpes, influençant fortement leur diversité génétique et leur potentiel évolutif. L'analyse de populations locales en situations contrastées à l'aide de marqueurs AFLP montre qu'au sein d'une lignée présentant une grande expansion, la diversité génétique est façonnée par des forces évolutives différentes selon le contexte écologique et historique. Les populations persistant présentent une dispersion des gènes restreinte, engendrant une diversité génétique assez faible, mais semblent adaptées aux conditions locales de l'environnement. À l'inverse, les populations colonisant la marge altitudinale sont influencées par les effets de fondation conjugués à une importante dispersion des gènes et, si ces processus impliquent une grande diversité génétique, ils engendrent une répartition aléatoire des génotypes dans l'environnement. Les autopolyploïdes apparaissent ainsi comme capables de persister face aux changements climatiques grâce à certaines facultés d'adaptation locale et de grandes capacités à maintenir une importante diversité génétique lors de la recolonisation post-glaciaire. Summary The extreme climate changes of the Quaternary have had a major influence on species distribution and evolution. The European Alps offer a great framework to investigate flora reactivity and the adaptive potential of species under changing climate. Some hypotheses postulate diversification due to vegetation removal and important isolation in southern refugia (Tabula Rasa), while others explain phylogeographic patterns by the survival of species in favourable Nunataks within the Alps. Since numerous species have successfully reacted to past climate changes by genome multiplication (autopolyploidy), studies of such taxa in natural conditions is likely to explain the ecological success and the advantages of autopolyploidy. Early cytogeographical surveys of Biscutella laevigata have shed light on the links between autopolyploidy and glaciations by indicating that diploids are now spatially isolated in never-glaciated areas, while autotetraploids have recolonised the zones covered by glaciers- during the last glacial maximum. A periglacial context apparently favoured this young autopolyploid complex but the circumstances and the advantages of this genomic mutation remain unclear. What is the glacial history of the B. laevigata autopolyploid complex? Are there multiple events of polyploidisation? To what extent do they affect the genetic diversity and the evolutionary potential of polyploids? Is recolonisation associated with adaptive processes? How does long-term persistence affect genetic diversity? The present study addresses these questions at different spatiotemporal scales. A regional survey at the Western Alps-scale tackles distal factors (evolutionary history), while local-scale studies explore proximal factors (evolutionary mechanisms). In the Western Alps, populations have been densely sampled and studied from the (1) cytotypic, (2) morphotaxonomic, (3) habitat point of views, as well as (4) plastid DNA molecular markers, in order to infer their relationships and establish the maternal lineages phylogeography. At the local scale, populations persisting at the rear edge and populations recolonising the attitudinal margin at the leading edge have been studied by AFLPs to show how genetic diversity is shaped by different evolutionary forces across the species range. The results at the regional scale document the glacial history of a widespread species, representative of alpine meadows, in a regional area of main interest (glacial refugia, main barriers and recolonisation routes) and points out to sites of interest for regional biodiversity. The external Alps have played a major role in the maintenance of populations near the central Alps during the Last Glacial Maximum and influenced the evolution of the species, and of vegetation. Polytopic autopolyploidy in different biogeographic districts is also demonstrated. The species has had an important and rapid radiation because recolonisation took place from different refugia. The subsequent recolonisation of the Western Alps was achieved by independent lineages that are presently admixing in the central Alps. The role of the Pennic summit line is underlined as a great barrier that was permeable only through certain favourable high-altitude passes. The central Alps are thus viewed as an important crossroad where genomes with different evolutionary histories are meeting and admixing. The AFLP analysis and comparison of local populations growing in contrasted ecological and historical situations indicate that populations persisting in the external Alps present restricted gene dispersal and low genetic diversity but seem in equilibrium with their environment. On the contrary, populations colonising the attitudinal margin are mainly influenced by founder effects together with great gene dispersal and genotypes have a nearly random distribution, suggesting that recolonisation is not associated with adaptive processes. Autopolyploids that locally persist against climate changes thus seem to present adaptive ability, while those that actively recolonise the Alps are successful because of their great capacity to maintain a high genetic diversity against founder effects during recolonisation.

The Effect of Teacher Expectations on Student Achievement: Does The Pygmalion Effect Hold True for Cape Verde?

The present study is about the relationship between teacher expectations and student achievement. Do teachers have the power to influence student achievement? This is the question at hand. Are students under the influence of their teachers in regards to how they perceive themselves as achievers and ultimately how well they perform? What are the other factors that come into play when assessing student’s academic achievement? In light of the literature written on this topic, the two most prevalent theories are (1) Pygmalion in the Class and (2) The Sustaining Effect. These theories show a direct and determinant relationship between teacher expectations and student achievement. The main objective of this study was to investigate if in Cape Verde, teachers follow the same trend. Responses to teacher and student surveys carried out at Domingos Ramos High School gave revealing insights into how Capeverdean teachers view their students and the role the teachers themselves play in supporting the studen’s academic performance. Is the teacher’s expectation of their students the last word? In general, teachers do have a powerful influence on their students for good or for bad, but the key questions are: (1) are they aware of this power and (2) how well do they manage it? This paper includes an in-depth discussion on the different factors that influence student achievement and research carried out at an urban secondary school which characterizes how teachers and students view their roles in the student’s academic success. Recommendations are also provided to assist teachers in managing their expectations to maximize their role as a positive contributor to the success of their students.

Aleo Vera living barriers - Cape Verde - Barreiras Vivas de Aleo vera (Portuguese)

Projecto DESIRE - Cabo Verde