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Background and Aims The Canary Islands have strong floristic affinities with the Mediterranean Basin. One of the most characteristic and diverse vegetation belts of the archipelago is the thermophilous woodland (between 200 and 900 m.a.s.l.). This thermophilous plant community consists of many non-endemic species shared with the Mediterranean Floristic Region together with Canarian endemic species. Consequently, phytogeographic studies have historically proposed the hypothesis of an origin of the Canarian thermophilous species following the establishment of the summer-dry mediterranean climate in the Mediterranean Basin around 2.8 million years ago. Methods Time-calibrated phylogenies for 39 plant groups including Canarian thermophilous species were primarily analysed to infer colonization times. In particular, we used 26 previously published phylogenies together with 13 new time-calibrated phylogenies (including newly generated plastid and nuclear DNA sequence data) to assess whether the time interval between stem and crown ages of Canarian thermophilous lineages postdates 2.8 Ma. For lineages postdating this time threshold, we additionally conducted ancestral area reconstructions to infer the potential source area for colonization. Key Results A total of 43 Canarian thermophilous lineages were identified from 39 plant groups. Both mediterranean (16) and pre-mediterranean (9) plant lineages were found. However, we failed to determine the temporal origin for 18 lineages because a stem–crown time interval overlaps with the 2.8-Ma threshold. The spatial origin of thermophilous lineages was also heterogeneous, including ancestral areas from the Mediterranean Basin (nine) and other regions (six). Conclusions Our findings reveal an unexpectedly heterogeneous origin of the Canarian thermophilous species in terms of colonization times and mainland source areas. A substantial proportion of the lineages arrived in the Canaries before the summer-dry climate was established in, Depto. de Biodiversidad, Ecología y Evolución, Fac. de Ciencias Biológicas, TRUE, pub

El 19 de septiembre de 2021 tuvo lugar el inicio de la erupción del volcán de Tajogaite en la vertiente oeste de la dorsal de Cumbre Vieja en la isla de La Palma. Después de 85 días de actividad, ésta ha sido la erupción histórica más larga en la isla y la octava que ha tenido lugar en periodo histórico, después de los volcanes de Tacande (1480), Jedey (1585), Martín y El Búcaro (1646), Fuencaliente (1677), El Charco (1712), San Juan, Hoyo Negro y Duraznero (1949) y Teneguía (1971). Ha sido uno de los volcanes mejor monitorizados desde el punto de vista geológico, pero los efectos de una erupción volcánica sobre la biodiversidad nunca habían sido estudiados simultáneamente al evento eruptivo. La mayoría de los trabajos científicos en esta materia se han dirigido a conocer cuáles son los procesos de regeneración de la vegetación y de la sucesión ecológica una vez finalizadas las erupciones volcánicas. Por ello, el objetivo de este estudio es detallar cómo se plantearon los métodos de seguimiento de la biodiversidad en unas condiciones ambientales adversas como las producidas por la erupción de un volcán. Asimismo, se trató de responder algunas cuestiones relativas a sus efectos sobre las especies de la flora y fauna insular: ¿Están las especies insulares «adaptadas» a los factores de estrés provocados por el volcanismo? ¿Hay algunos tipos funcionales de plantas vinculados a ellos? El estudio de las escalas temporales y espaciales de esos patrones ayudará a conocer en qué medida estos eventos naturales catastróficos constituyen ventanas de oportunidad para que se produzcan o aceleren los procesos evolutivos que tienen lugar en la biota de islas oceánicas.

Background and Aims The Canary Islands have strong floristic affinities with the Mediterranean Basin. One of the most characteristic and diverse vegetation belts of the archipelago is the thermophilous woodland (between 200 and 900 m.a.s.l.). This thermophilous plant community consists of many non-endemic species shared with the Mediterranean Floristic Region together with Canarian endemic species. Consequently, phytogeographic studies have historically proposed the hypothesis of an origin of the Canarian thermophilous species following the establishment of the summer-dry mediterranean climate in the Mediterranean Basin around 2.8 million years ago. Methods Time-calibrated phylogenies for 39 plant groups including Canarian thermophilous species were primarily analysed to infer colonization times. In particular, we used 26 previously published phylogenies together with 13 new time-calibrated phylogenies (including newly generated plastid and nuclear DNA sequence data) to assess whether the time interval between stem and crown ages of Canarian thermophilous lineages postdates 2.8 Ma. For lineages postdating this time threshold, we additionally conducted ancestral area reconstructions to infer the potential source area for colonization. Key Results A total of 43 Canarian thermophilous lineages were identified from 39 plant groups. Both mediterranean (16) and pre-mediterranean (9) plant lineages were found. However, we failed to determine the temporal origin for 18 lineages because a stem–crown time interval overlaps with the 2.8-Ma threshold. The spatial origin of thermophilous lineages was also heterogeneous, including ancestral areas from the Mediterranean Basin (nine) and other regions (six). Conclusions Our findings reveal an unexpectedly heterogeneous origin of the Canarian thermophilous species in terms of colonization times and mainland source areas. A substantial proportion of the lineages arrived in the Canaries before the summer-dry climate was established in

Rabbits have travelled with humans to the most remote archipelagos, having been introduced on at least 800 islands worldwide. This herbivore has caused a devastating effect on endemic insular plants, causing changes in species composition, cascading extinctions and disruption of native seed dispersal systems worldwide. However, its ecological impacts as disrupting native seed dispersal systems have not been studied from a holistic perspective in any of the archipelagos where rabbits were introduced. Here, we assess the role of rabbits as frugivores and seed-dispersers on the most extensive and diverse island of the Canary Archipelago, Tenerife, across its five main vegetation zones represented in an altitudinal gradient 0–3715 m a.s.l. To this end, 120 transects per vegetation zone were conducted (August 2020–November 2021) to collect fresh faecal samples from a total of 244 latrines. They consisted of 29,538 droppings in which we found seeds from 73 plant species, 29 of which were identified to species level (13 endemic, eight natives and eight introduced by humans). About 70% of the seeds were identified as fleshy-fruited plant species while the remaining nine were dry fruits. Of the former, only nine showed a percentage of intact seeds greater than 75%, another nine species between 50 and 75%, and three lower than 50%. The digestive effect of rabbits on seedling emergence was generally low, compared to that produced by native seed dispersers. Since fleshy-fruited plants and rabbits have not been linked in their evolutionary history in the Canaries, the former seems to have their own legitimate seed dispersers.

Pigeons are considered to play key ecological roles in frugivory and seed dispersal. They have colonised numerous oceanic islands and diversified into several species in sympatry. How these species coexist in similar niches is poorly understood although dietary separation is among the mechanisms suggested to avoid trophic overlap. We investigated the trophic ecology of the two endemic Columba species co-occurring in the laurel forest and thermosclerophyllous relicts of two of the Canary Islands. This study includes diet description in spatiotemporal terms, its relationship with fruit availability and seed treatment in 10 study areas established on La Palma and La Gomera. We used non-invasive DNA analysis to identify the faeces of the two con-generic species and microhistological methods to examine their diets. The degree of trophic overlap was evaluated by niche similarity and breadth indices. Molecular faecal sampling determined the spatiotemporal distribution of both pigeons to identify their areas of coexistence. These frugivorous pigeons’ diets did not differ concerning the main plant species, but they diverged quantitatively in the proportions and parts of plants consumed. Lauraceae fruits were their staple foods although Rhamnaceae and some Fabaceae and Solanaceae were also important. Both pigeons showed selective preferences for some fruits. Significant spatiotemporal variations in their diets were observed along with a general tendency to increase fruit intake at its ripening times. Our results suggest that different trophic strategies facilitate the coexistence of these frugivorous columbids. These pigeons act as seed dispersers and/or predators depend ing on seed features (size and hardness), and this may have valuable implications for their conservation.

Many fleshy-fruited plants from the Mediterranean and Macaronesian islands are dispersed through endozoochory. In mainland Mediterranean areas, reciprocal adaptations have been found between plants and animals, although evidence is scarce. On small isolated oceanic islands, such reciprocal adaptations might well be more prevalent due to intrinsic island traits. Here we evaluate the existence of selective pressures exerted by two different disperser guilds (lizards and birds) on two seed traits (seed coat thickness and seed germination pattern) of two congeneric species present on Mediterranean and Macaronesian islands. In the continental Balearic Islands, Rubia peregrina has evolved mostly with birds, although frugivorous lizards are present in some of these islands and are known to eventually consume its fruits. By contrast, R. fruticosa, endemic to the Macaronesian archipelago, has evolved mostly interacting with lizards and only recently with birds. We hypothesized that R. fruticosa would be especially adapted to saurochory, with thicker seed coats and higher germination proportion, whereas R. peregrina would be more adapted to ornithocory, with thinner seed coats and showing a lower germination percentage after being ingested by lizards. Captivity experiments of seed ingestions by natural and non-natural dispersers (i.e., frugivores that have not evolved with those plants) were conducted. Results suggest that dispersers did not exert any strong enough selective pressure to induce changes in germination patterns. We attribute this to the fact that the Rubiaceae is an ancestral family in the Mediterranean (both on continent and islands) and thus probably interacted with lizards in the past. Lastly, although we hold that the seed coat structure of R. fruticosa is probably associated with its evolutionary success after a long interaction with insular lizards, our findings support the idea that the relationship between endozoochorous plants and the guild of disperser

The design, synthesis and binding affinity for VEGFR-1 receptors of a small library of linear and cyclic analogues of the VEGF81–91 fragment are described. Cyclic 11- and 10-mer peptide derivatives were prepared using parallel solid-phase protocols. The formation of hydrocarbon alkene-bridged cyclic peptides was achieved through optimized ring-closing metathesis reactions from linear derivatives with conveniently located allylGly residues. Alkane-bridged analogues were successfully obtained by ulterior on-resin hydrogenation. Binding assays showed that some of these compounds were able to compete with labeled VEGF for interaction with the VEGFR-1 receptor. Several peptide derivatives, 2, 7 and 8, showed modest but significant binding affinity, indicating that the designed peptide could mimic the VEGF81–91 fragment and therefore disrupt the VEGF/VEGFR-1 interaction. This fact opens the way for using these peptides as the starting point for biological/pharmacological tools to deeply investigate this protein–protein system.

El presente proyecto comprende el estudio sistemático de la ecología trófica de las palomas turqué (Co- lumba bollii) y rabiche (C. junoniae), especies endémicas de las Islas Canarias. Estas aves frugívoras habitan en simpatría en los relictos bosques de laurisilva. El estatus de amenaza de estas especies y su conducta evasiva, supone que el manejo de ejemplares y las observaciones de campo resulten muy complicados. Por tanto, en este estudio se aborda el desarrollo de técnicas moleculares usando muestras no invasivas, plumas y excrementos, procedentes de diferentes individuos de cada una de las dos especies. En primer lugar, se analizó la variabilidad inter e intraespecífica de las secuencias de la región control del ADN mitocondrial de las poblaciones de palomas presentes en el Parque Nacional de Garajonay en la isla de La Gomera. Posteriormente, los excrementos (similares morfológicamente), fueron identificados a nivel de especie usando la técnica molecular de RFLP. Además, debido a la baja con- centración del ADN fecal y la presencia de inhibidores en las muestras, se diseñó un método de extracción del ADN que permitió el incremento de la tasa de amplificación. Este método fue utilizado por vez primera, para la extracción y amplificación del ADN de las palomas presente en la superficie de las semillas regurgitadas. Una vez identificadas las muestras fecales, se procedió al análisis microhistológico de sus contenidos. Para ello, fue necesaria la elaboración de una extensa colección de referencia de las epidermis de las hojas, flores, frutos y semillas de las principales especies de plantas presentes en el diverso bosque de laurisilva, y que pudieran ser potencialmente consumidas por las palomas. Se realizó una clave de identificación de las epidermis foliares y de frutos de las más de veinte especies arbóreas presentes en los bosques de laurisilva. Por último, aplicando esta metodología, se estudia la distribución de las palomas turqué y rabiche en el Parque Naci

The success of many alien plant species depends on mutualistic relationships with other species. We describe the assemblage of seed dispersers on three species of alien Opuntia invading Mediterranean and Macaronesian habitats, and examine the quality of such plant-animal interactions. We identified vertebrates consuming O. maxima, O. dillenii and O. stricta fruits by direct observation and collecting droppings and pellets. Phenology of the alien species, as well as that of coexisting native species, was monitored for an entire year. Germination tests of ingested and non-ingested seeds were performed both in the greenhouse and in the field. Seed coat thickness and viability were also measured for all treatments. A great variety of taxa, including reptiles, birds and mammals actively participate in the seed dispersal of Opuntia. Phenology of Opuntia fruits in Menorca and Tenerife overlaps with only a few native fleshy-fruited plants present in the study areas, which suggests an advantage for the invader. Most seeds germinated during the second year of the experiment, independently of the effect produced by the dispersers’ guts. We found great variation in the germination percentage of Opuntia after gut passage and in the effects of ingestion on seed coat thickness. Seed viability was somewhat reduced after gut passage compared to manually depulped seeds. Our results show how different Opuntia species are integrated into native communities by means of mutualistic interactions, with both native and alien dispersers. Although with heterogeneous effects, either type of disperser potentially contributes to the spread of these alien cacti in the recipient areas.

Capsule Faecal DNA gives accurate results of habitat use.

DNA extraction methods for genotyping non-invasive samples have led to great advances in molecular research for ecological studies, and have been particularly useful for analyzing threatened species. However, scarce amounts of fragmented DNA and the presence of Taq polymerase inhibitors in non-invasive samples are potential problems for subsequent PCR amplifications. In this study we describe a novel technique for extracting DNA from alimentary tract cells found on external surfaces of feces and regurgitated seeds. The presence of contaminants and inhibitors is minimized and samples are preserved intact for use in other ecological research (e.g. trophic studies). The amplification efficiency and purity of the extracted DNA from feces were significantly higher than in commonly used extraction procedures. Moreover, DNA of two bird species was identified from seeds expelled by regurgitation. Therefore, this method may be suitable for future ecological studies of birds, and other vertebrate groups.

Seed germination percentage and rate of Rubia fruticosa, an endemic Macaronesian shrub was assessed with seed lots collected at three levels of an altitudinal gradient (200–800 m asl) located in El Hierro Island (Canarian Archipelago). Both seeds collected from control plants and those found in lizard droppings were studied. A significant decrease in the germination percentage was observed with control seeds and those seeds which are previously eaten by lizards if collected at 800 m asl. This indicates that R. fruticosa is a plant whose optimal germination environment is located between 200 and 500 m asl, occurring in higher altitudes only under sub-optimal conditions. The effect of lizard gut on R. fruticosa seeds was variable in the two study years: while germination percentage of seeds having passed through the lizards was not significantly different to that of control seeds in the first year, an increased germination was found for the animal-treated seeds in all three altitudinal zones in the second year. In general, germination rate of control seeds was rather variable between years. However, improvement of R. fruticosa seed germination caused by lizards may be important for its fitness; and a co-evolution may have occurred, since lizards and seeds of this endemic plant have been intensively interacting for millions of years in the lower zones of the Canary Islands.

DNA extraction methods for genotyping non-invasive samples have led to great advances in molecular research for ecological studies, and have been particularly useful for analyzing threatened species. However, scarce amounts of fragmented DNA and the presence of Taq polymerase inhibitors in non-invasive samples are potential problems for subsequent PCR amplifications. In this study we describe a novel technique for extracting DNA from alimentary tract cells found on external surfaces of feces and regurgitated seeds. The presence of contaminants and inhibitors is minimized and samples are preserved intact for use in other ecological research (e.g. trophic studies). The amplification efficiency and purity of the extracted DNA from feces were significantly higher than in commonly used extraction procedures. Moreover, DNA of two bird species was identified from seeds expelled by regurgitation. Therefore, this method may be suitable for future ecological studies of birds, and other vertebrate groups.

Size-related selection of insular lizards by two sympatric predatory bird species (Southern Grey Shrike and Eurasian Kestrel) was studied in an arid insular environment. The endemic lizard genus Gallotia was a key resource in the diet of both predators, constituting more than 50% of the total biomass. Shrikes captured smaller lizards than kestrels during all seasons (mean snout-vent length (SVL): 7.4 ± 1.9 vs. 9.4 ± 2.1 cm respectively), presenting a sequential use of lizard sizes and avoiding potential competition. On the other hand, shrikes and kestrels showed the same seasonal variation pattern, capturing the largest lizards during their breeding periods (spring). Considering lizard availability, shrikes displayed less selective predation than kestrels in all seasons. Shrikes positively selected the medium lizard size (SVL: 5-10 cm) during the nestling period, but negatively selected the small lizard size (SVL: < 5 cm) in autumn and winter, probably due to an explosion of juvenile lizards. Lastly, kestrels appeared to be more selective, negatively choosing the small lizard size but positively selecting the largest ones all the year round (SVL: > 10 cm).

The diet of the endemic Madeira Laurel Pigeon Columba trocaz in agricultural and forest areas of Madeira Island was studied in 1997 by means of microhistological analysis of 157 faecal samples, 94 from two of the main agricultural zones and 63 from a laurel forest. Cabbage was the most important component of the diet in agricultural areas, representing more than 54% of the optical fields analysed. Samples collected further from the forest contained a higher proportion of cabbage. Native fruits did not figure highly in the samples collected from agricultural areas and crop plants did not appear in the forest samples, suggesting a degree of dietary separation and that some individuals may concentrate on crops. Madeira Laurel Pigeon is normally a highly frugivorous species and fruit availability is relatively high is winter when the birds go to agricultural areas to feed. This suggests that it is not a shortage of natural foods that causes them to leave the forest. The unpopularity of the pigeon as a result of its pest status is the main threat to its existence. More information on the seasonal physiological requirements of Madeira Laurel Pigeon and the pattern of individual use of crops is needed to ensure the future conservation of this species.