Estudio de los braquiópodos fósiles del neógeno y pleistoceno de las canarias orientales : citas actuales

Braquiópodos Pliocenos y Pleistocenos de las Canarias Orientales con mención de los actuales Pliocene and Pleistocene Brachiopods from Eastern Canary Islands with actual references Máster en Oceanografía EDUARDO GONZÁLEZ ÁLVAREZ Tutor: Prof. Dr. Ignacio Alonso Co-tutor: Dr. Joaquín Meco, Profesor Emérito 2013 1 Braquiópodos pliocenos y pleistocenos de las Canarias orientales con mención de los actuales. Pliocene and Pleistocene Brachiopods from Eastern Canary Islands with actual references. Eduardo González Álvarez; DNI: 45330221G; dirección Paseo de Las Canteras, nº 70, 1er piso; tlfn: 610056590; e-mail: e[email protected] Máster en Oceanografía Tutor: Dr. Ignacio Alonso Bilbao, profesor titular de la ULPGC, Instituto de Oceanografía y Cambio Global (IOCAG), Departamento de Física, Facultad de Ciencias del Mar. Co-tutor: Dr. Joaquín Meco Cabrera, profesor emérito de la ULPGC, Laboratorio de Paleontología y Paleoceanografía, Departamento de Biología, Facultad de Ciencias del Mar. En Las Palmas de Gran Canaria, a 3 de Diciembre de 2013. Autor Tutor Co-tutor Eduardo González Álvarez Ignacio Alonso Bilbao Joaquín Meco Cabrera Fdo.:………………………. Fdo.:………………………. Fdo.:…………………… 2 Index 1. Introduction.........................................................................................................4 1.1. Objective.........................................................................................................4 1.2. Geological context..........................................................................................4 1.3. Stratigraphic provenance of canaries fossil brachiopods..............................4 1.4. Paleoclimatical and paleoecological information..........................................9 2. Methodology.......................................................................................................10 3. Systematic and taxonomy..................................................................................10 3.1. The brachiopods...........................................................................................10 3.2. Fossil brachiopods…………………………………………….……….…..14 3.3. Actual brachiopods……………………………………………………...…18 4. Discussion...........................................................................................................21 5. Conclusions.........................................................................................................24 Plate I and II......................................................................................................26 Acknowledgments..............................................................................................27 References……………………………………...……………………………....27 3 Pliocene and Pleistocene Brachiopods from Eastern Canary Islands with actual references. Autor: Eduardo González Álvarez Abstract The study of fossil fauna and the available literature, allows us to give an interpretation of paleoclimatic character to the presence of brachiopods, associated with their fossil state to weather conditions very different that nowadays, being equivalent to the present tropical regions of the planet. It is studied, therefore, the faunal content from the fossiliferous sedimentary deposits of Pliocene (5-3 My) and Pleistocene (3 Myr-10 kyr) age present in Gran Canaria, Fuerteventura and Lanzarote -eastern Canary Islandspaying special attention to those observed fossil brachiopods. It has undertaken a review of previous work and the study of the deposits of Pliocene and Pleistocene age, as well as the revision of the fossil collections of the Laboratory of Paleontology at the University of Las Palmas de Gran Canaria. This has allowed the identification of 4 species of fossil brachiopods: Terebratula sinuosa (Brocchi 1814), Lacazella mediterranea (Risso 1826), Terebratulina caputserpentis (Zbyszewski, 1957) and Thecidium cf. digitatum (Sowerby 1823). These fossils have been identified in outcrops of Pliocene age from the eastern Canary Islands, described and illustrated in the work of Meco et al. (2005) and in outcrops interpreted as coming from an marine event of great energy or tsunami in Piedra Alta, Lanzarote, belonging to Marine Isotope Stage 11 (MIS 11) in circa 480 kyr. Furthermore, in order to compare the fossil brachiopods with existing, it has been defined a reference collection with actual specimens obtained from the pickup of surface sediment samples made in Gran Canaria and Hierro, identifying 3 species: Argyrotheca barrettiatia (Davidson, 1866), Megerlia truncata (Linaeus 1767) and Pajaudina atlantica (Logan 1988). Key words: Brachiopods, Pleistocene, paleoclimatic indicators, North Atlantic. 4 1. Introduction 1.1. Objective Studies about brachiopods in the Canary Islands are rare. In fact, the only appointment on current brachiopods in the Canary Islands corresponds to the work of Logan (1988) and concerning fossil species were never mentioned in the scientific literature until recently in a doctoral thesis on Mio-Pliocene fauna of the islands (Betancort, 2012) where two species of this taxonomic group are mentioned. The objective of this paper aims to fill this gap, and to do a new line of research on the phylum of brachiopods in the context of paleontological research works carried out by the ULPGC (Universidad de Las Palmas de Gran Canaria). 1.2. Geological Context On the other hand, Moreover, the marine deposits of the Canary Islands and its fossil content have been studied since the XIX century (Lyell 1865, Rothpletz & Simonelli 1898) and have resulted in numerous publications (see Meco et al., 2007). In addition, the geological context of the archipelago is well known and already exists a number of radiometric dating (Carracedo et al., 2002). Finally, the large marine fauna accompanying the few fossil brachiopods has allowed recreate the paleoclimate common to them. (Meco et al., 2005, 2006, 2008; Betancort 2012; Muhs et al, in press.). 1.3. Stratigraphic provenance of canaries fossil brachiopods. The specimens studied are from fossiliferous marine deposits mainly constituted by sandstones and conglomerates of relatively low thickness with an average of a couple of meters but its extent is very large and appears in the three eastern islands: northwest of Gran Canaria, West Coast of Fuerteventura surrounding Jandía peninsula and southeast of Lanzarote (Fig. 6). These deposits are dated radiometrically at about 5 Myr (million of years) for a pillow lavas in Ajuí Ravine, Fuerteventura (Meco & Stearns 1981; Coello et al., 1992; Meco et al.; 2007), and others in Gran Canaria in about 4 Myr (Guillou et al., 2004) which set them in the lower Pliocene. The pillow lavas indicate rapid cooling in this case when take contact with seawater so it is considered that the age of the pillow lavas is the same of the marine deposits associated with them. The height of the marine deposits is more higher in Gran Canaria than the other islands, 5 where it reaches 120 m, which has been inferred the existence of uplifts in the archipelago (Meco et al., 2007). Figure 1. Geological maps of Gran Canaria, Fuerteventura and Lanzarote. In each of them is marked with a line or dots in the case of Lanzarote, where marine deposits braquiópdos were collected. 6 Figure 2. Summary of the geology of Fuerteventura in simplified form: a1) basal complex submarine volcanism, a2) basal complex almost metamorphosed sedimentary deposits, b) discordant Miocene basalts of the basal complex, c) marine deposits containing brachiopods and dated by the lava, d) Pliocene basaltic pilow lavas dated at 5.8 Myr, 5 Myr, 4.8 Myr and Pliocene-covered dunes, e) Mid-Pleistocene volcanism installed on Mid-Pleistocene dunes. 7 But they have also appeared other fossil brachiopods in marine deposits dated using uranium series on coral in 480 kyr (Muhs et al., In press). Deposits show a violent or storm character so they have been attributed to a possible tsunami (Fig. 5). The age obtained from corals and the whole fauna put the deposits in the Mid-Pleistocene, probably in the interglacial MIS 11 (Marine Isotope Stage). Finaly, the present brachiopods come from surface sediment samples taked in Gran Canaria and El Hierro (Fig. 6 and Tab. 2) by the Laboratory of Sedimentology from the ULPGC and deposited in the Laboratory of Paleontology. Sites where brachiopods were collected: Gran Canaria Pliocene fossiliferous marine deposits - Ciudad Jardín (Fig. 3) - Arenales - Barranco Seco (Fig. 3) Figure 3. Left image: fossil brachiopod (Terebratula sinuosa) found in Ciudad Jardín; scale of 5 cm. Right image: Marine Pliocene conglomerate in Barranco Seco. 8 Fuerteventura Pliocene fossiliferous marine deposits - Coast of Barlovento: between Santa Inés and Los Molinos (Fig. 4) Figure 4. Pliocene marine deposits in Fuerteventura. The image on the left shows the deposit located on the floor, on the right, Pliocene fossil life agglomeration. Lanzarote Fossiliferous marine deposits (tsunami or storm) of MIS 11 (Mid-Pleistocene) - Piedra Alta (Fig. 5) Figure 5. Marine deposits associated with a turbulent process or tsunami in Piedra Alta, Lanzarote, dated to MIS 11 (480 kyr). 15 Material: 6 whole specimens and numerous fragments from many other animals in the Barranco Seco (Gran Canaria) were found. Full specimens of Barranco Seco were at the same sand level within the deposit; in the same strip of fine sand and very close to each other and the foramen to the substrate. Whole specimens have varying degrees of conservation but are totally enclosed, with two valvas and highlights one having a strange twist. Canary locations: Gran Canaria: Barranco Seco, Ciudad Jardín. Stratigraphic and geographic distribution: Species cited to the Miocene and Pliocene of the Mediterranean, especially abundant in the Italian basin deposits. It was first described by Brocchi (1814) for Piacenziens deposits (Late-Pliocene) of Northern Italy. Davidson (1870) also cited for the Miocene-Pliocene transit. Original diagnosis: Original diagnosis obteined from Brocchi 1814: “Testa oblonga, valva superiore uniplicata, altera biplicata, margne infero sinuoso, ápice perforato” Description: highlight characteristic of this species a remarkable development of the grooves on the valvas causing a bifolded anterior commissure (Calzada Badia, 1978). Considerable variation in outline, relative width, thickness and shape of the ribs. The curious concentration and agglomeration of the specimens found in Barranco Seco, undamaged and unmarked transport, partially covered in the same strip of very fine sediments, suggests some kind of "grouping in life." Superfamily Cancellothyroidea Family Cancellothyrididae Thomson, 1926 Subfamily Cancellothyridinae Thomson, 1926 Genus Terebratulina D'Orbigny, 1847 Terebratulina caputserpentis (Zbyszewski, 1957) Plate I, Fig. 2a, 2b. 1887 Terebratulina caput-serpentis Fischer, P., Pl. XV, 3 1886 Terebratulina caputserpentis Granger, A., Pl. I, 2 Materials: One specimen, small, partially broken, only the dorsal valve. Canary locations: Gran Canaria: Arenales (La Minilla). 16 Stratigraphic and geographic distribution: Relatively common and widespread. Cited since Miocene to the present. Actual since North Sea (Scandinavia) to the Mediterranean. Caribbean Sea and east coast of North America. Miocene deposits of the Mediterranean (Hungary, Spain) and Atlantic islands of Azores, Santa Maria. Pleistocene deposits in southern Taiwan, South China Sea. Description: Subpentagonal-oval shell, longer than wide. Surface covered with fine radial striations. Opening the horseshoe-shaped lophophore. It is considered synonymous Terebratulina retusa (Linne, 1758). Emig (2002) cites the following synonyms: Anomia caput-serpentis Linné, 1767 Anomia pubescens Linné, 1767 Terebratula retusa Retzius, 1788 Criptoderma caputserpentis Poli 1795 Terebratula aurita Fleming, 1822 Terebratula costata Lowe, 1825 Terebratula emarginata Risso, 1826 Terebratula quadrata Risso, 1826 Delthyris spatula Menke, 1830 Terebratula caput-serpentis Sowerby, 1847 Terebratulina caputserpentis d'Orbigny, 1847 Terebratula striata Leach, 1852 Terebratulina retusa Dall, 1920 Nowadays, it often lives in vertical walls and hard substrates, mainly shells of bivalves (mainly Modiolus modiolus Linnaeus, 1758) and sponges on a very wide range of depths, from shallow water (3 m) to about 1500 m (Bitner & Doan, 2004). Order Spirifera Waagen, 1883. Suborder Thecideidina Elliot, 1958 Superfamily Thecideacea Gray, 1840 Family Thecideidae Gray, 1840 Subfamily Lacazellinae Backhaus, 1959 Genus Lacazella Munier-Chalmas 1881 17 Lacazella mediterranea (Risso, 1826) Plate I, Fig. 3a, 3b. 1988 Lacazella mediterranea Logan, p. 550, fig. 2,4. 2005 Lacazella mediterranea Logan, p. 103, fig. 4.1. 2012 Lacazella mediterranea Betancort, Plate V, fig. 6-12 Material: Numerous ventral and dorsal valvas in poor condition. Canary locations: Gran Canaria: Ciudad Jardín. Fuerteventura: Coast of Barlovento (between Ajuí Ravine and Los Molinos Ravine). Original diagnosis: “Testa subrotundata, inaequali, lutescente pustulata interne candidísima”. Stratigraphic and geographic distribution: Oligocene-Present stratigraphic distribution according Logan (2004b). It is present in the Miocene and Pliocene deposits of the Mediterranean. Almera (1907) cite it in the synonymy of Thecidea Mediterranean, Risso mentions it for the Pliocene deposits of Llano de Llobregat and Barcelona. Currently located on the Mediterranean Coast. Description: Adult shell rarely exceeds 5 mm long, convex shell, dorsal valva usually flat, semicircular-shaped rather than round. Pale brown shell with irregular concentric lamellae that sometimes shown growth. Cardinal flat, triangular, with triangular flat belly deltidium area. Subphylum Rhynchonelliformea Williams, Carlson y Bruton, 1996 Class Rhynchonellata Williams, Carlson y Bruton, 1996 Order Thecideida Elliot, 1958 Superfamily Thecideoidea Gray, 1840 Family Thecideidae Gray, 1840 Subfamily Thecideinae Gray, 1840 Genus Thecidium G.B. Sowerby, 1823 Thecidium cf. digitatum (Sowerby, 1823) Plate I, Fig. 4a, 4b. 18 1823 Thecidium digitatum (Sowerby 1823, The Genera of Recent and Fossil Shells, for the use of students ). PL. XXVI, fig. 16. 1867 Thecidium digitatum Urban Schloenbach, Tab. XXIII, Fig 14 2012 Thecidium digitatum Emig, C.C., Fig 3 y 5. Material: one specimen, dorsal valva Canary locations: west coast of Fuerteventura, Barlovento Stratigraphic and geographic distribution: unknown Description: This is a fossil specimen found to the Pliocene and which references are very scarce. Described in a catalog by Sowerby 1823, the specimen he describe has up to 6 lobes, whereas our sample represents only 4 although they are virtually identical in appearance. It is not known whether because our sample was in an immature stage or was perhaps either sex who present these features. 3.2. Actual brachiopods Table 2. Actual brachiopods identified in this work in Canary waters. Station (Sample) Coordinates Depth Brachiopods Observations E4 27º46.98’ N 15º22.05’ O 80 m Megerlia truncata Specimens highly fragmented E5 27º47.02’ N 15º21.06’ O 84 m Megerlia truncata, Argyrotheca barrettiana Good condition of conservation N23 28º09.857’ N 15º31.961’ O 93 m Megerlia truncata Good condition of conservation El Hierro 21 m Pajaudina atlántica Numerous specimens, agglomerated together 19 Subphylum Rhynchonelliformea Williams, Carlson, Brunton, Holmer y Popov, 1996 Class Rhynchonellata Williams, Carlson, Brunton, Holmer y Popov, 1996 Order Terebratulida Waagen, 1883 Suborder Terebratellidina Muir-Wood, 1955 Superfamily Kraussinoidea Dall, 1870 Family Kraussinidae Dall, 1870 Genus Megerlia King, 1850 Megerlia truncata (Linaeus, 1767) Plate II, Fig. C, D. 1886 Megerlia truncata Granger, A., Pl. I, 3 1887 Megerlia truncata Fischer, P., Pl. XV, 9 1968 Mühlfeldtia truncata Luther & Fiedler Pl. XV, fig. 9 2004b Megerlia truncata. Logan, p. 165 Material: three whole specimens and one totally fragmented. Canary Locations: Gran Canaria, North Coast (Station N23), East Coast (Station E4 and E5). Stratigraphic and geographic distribution: currently found in the Mediterranean Sea, further to the west than the east (Spain, France, Italy), northwest Africa and Macaronesia fairly widespread in the region. Description: ventral valve strongly arched, the dorsal with flat and presenting a slight longitudinal fold centrally located. Characterized by a biconvex shell ornamented with radiating ribs which are sometimes slightly nodular with irregular concentric lamellae, dotted growth. 20 Class Articulata Huxley, 1869 Order Spiriferida Waagen, 1883 Suborder Thecideidina Elliot, 1958 Superfamily Thecideacea Gray, 1840 Family Thecideidae Gray, 1840 Subfamily Lacazellinae Backhaus, 1959 Genus Pajaudina Logan, 1988 Pajaudina atlantica (Logan 1988) Plate II, Fig. A, B. 1988 Pajaudina atlantica Logan, p. 549, fig. 4. 2004a Pajaudina atlantica Logan, pp. 210, 212. fig. 1,3. 2005 Pajaudina atlantica Logan, p. 103, fig. 4.2. Material: many specimens, most of them agglomerated together, upper and lower valvas. Canary localities: El Hierro, approximately 20 m depth Stratigraphic and geographic distribution: Currently found only in the Canary Islands and the Holocene, without the presence of fossils anywhere in the world. Diagnosis: “Relatively large, elongate lacazellinin with prominet upraised and lobed median ramus complexy interdigitated with branches of minor interbrachial lobes” by Logan (1988). Description: Shell relatively large, elongated profile, longer than wide, biconvex. Long pedicle Valva. Interarea ventral valve flat, triangular and high pseudodeltidium. Small brachial valve. 21 Order Theceida Elliot, 1958 Suborder Terebratellidina Muir-Wood, 1955 Superfamily Megathyridoidea Dall, 1870 Family Megathyrididae Dall, 1870 Genero Argyrotheca Dall, 1900 Argyrotheca barrettiania (Davidson, 1866) Plate II, Fig. E, F. 1866 Argyrotheca barrettiana Davidson, Pl. XII, fig. 3a, 3b, 3c. 2007 Argyrotheca barrettiana Harper & Donovan, Pl. 3, fig. 1a-1b. Material: A single specimen, found in perfect condition. Canary locations: East coast of Gran Canaria (Station E5). Stratigraphic and geographic distribution: Currently described fossil for the West Indies, Jamaica, by Harper & Donovan (2007) for the Pleistocene and present, Holocene, to the Canary Islands. Description: white color (calcareous) with medium sized with valvas ventribiconvexas with semicircular transverse profile. Rounded, sharpened or perpendicular cardinal extremities. Evenly convex lateral profile. Ventral interarea flat to slightly curved. Deltidium long and open. Quite marked, thick and pronounced radial grooves. 4. Discussion In this study, 4 fossil species belonging for two different ages in the Canary Islands are distinguished. First, for the Pliocene deposits have been identified Terebratula sinuosa Lacazella mediterranean, Terebratulina caputserpenteis and Thecidium cf. digitatum species (Fig. 11 and Plate I). Terebratula sinuousa found in deposits of Gran Canaria (Barranco Seco and Ciudad Jardín) as well as Terebratulina caputserpentis (La Minilla) while Lacazella mediterranea, is well found in Gran Canaria (Ciudad Jardín) and in Fuerteventura (Barlovento Coast, between the Los Molinos ravine and Santa Inés) (Tab. 3). While are appointments of fossils of T. Sinuosa and L. Mediterranean (Betancort, 2012), in this work are found in the deposits and identify T. caputserpentis and Thecidium cf. digitatum being, both first record for the Neogene of the Atlantic islands. While T. caputserpentis is current and fairly common in the Atlantic and the 22 Mediterranean, citing it in the Canary Islands, this fossil appointment is a contribution that extends its presence in the Atlantic and Canary Islands until at least the Pliocene. Moreover L. mediterranea is present in the Mediterranean existing a big controversy with one of her closest relatives, Pajaudina atlantica (Logan, 1988). This paper adopts the criterion that L. mediterranea and P. atlantica are two different species. For this, the criterion was followed by the morphological examination of the inside of the valvas in both species (Fig. 11). These differ mainly in L. mediterranea presents a wider brachial valva while P. atlantica is longer reaching also in L. mediterranea larger sizes. Inside the valva, L. mediterranea lacks median ramus in the center, even though the specimen shown is pretty washed and eroded, as shown in Figure 11. P. atlantica not only presents this type of denticulated ramus, also has a welldefined ramulus of L. mediterranea lacks. Apparently the structure showing higher similarities are the major interbraquiales lobes, located at both ends of each valva. Other fossils of L. mediterranea, appear in Piedra Alta, Lanzarote, dating from the Middle Pleistocene (Muhs et al., in press) during MIS 11 interglacial. Currently L. mediterranea is not cited in the Canary Islands but is restricted to the Mediterranean region. However, it is cited for the Canary Islands P. atlantica, found in surface samples of El Hierro, at an aproximatly depth of 20 meters. It therefore considers that L. mediterranea is more related to ecosystems of high temperature or tropical-subtropical environments, being these the prevailing conditions in the Pliocene and the MIS 11 interglacial. Ecological conditions were significantly different from today. This is denoted by the accompanying fauna (Tab. 1) typically from warm character. There is no fossil records of brachiopods for the upper Pleistocene in the Canary Islands in the differents MIS 5.5 outcrops present in the islands: Fuerteventura, Lanzarote, Gran Canaria and Tenerife, have not been identified fossil brachiopods. It is accepted that the conditions of the Holocene (last 11.7 kyr) are sufficiently constant, so the current brachiopod fauna exists along the entire Holocene. 23 Figure 11. A-B Lacazella mediterránea; C-D Pajaudina atlántica; Specimen L. mediterranean belongs to deposits of Piedra Alta, Lanzarote (MIS 11). It Can be perfectly differentiated the morphology of both species in the ramus and ramulus, which L. Mediterranea lacked it. The study of materials from surface samples collected in Marine Sedimentary Environments practices, Faculty of Marine Science, by Professor Ignacio Alonso Bilbao in 2002 in the east and north of Gran Canaria (Tab. 2), allowed us to cite other actual species of brachiopods for the Canary Islands accompanying P. atlantica. These present species of brachiopods are Argyrotheca barrettiana and Megerlia truncata. A. barrettiana have been found fossil in the Pleistocene of the West Indies, Jamaica (Harper & Donovan, 2007), so in the Pleistocene may have a climate in Jamaica like we have today in the Canary Islands. Therefore oceanographic implications exist between 24 the Atlantic and the Mediterranean region, remaining reaffirmed that the North Atlantic Subtropical Gyre is able to function as a migration route for certain species. 5. Conclusions 1. Two new records of fossil brachiopods are contributing to the Pliocene from the Canary Islands that are also new records for the macaronesic region: Terebratulina caputserpentis (Zbyszewski, 1957) and Thecidium cf. digitatum (Sowerby 1823). 2. Furthermore of these species, two species mentioned above are confirmed, so there are now four known species for the Pliocene from the Canary Islands: Terebratula sinuosa (Brocchi, 1814) Lacazella mediterranea (Risso, 1826) Terebratulina caputserpentis (Zbyszewski, 1957) Thecidium cf. digitatum (Sowerby, 1823) 3. It contributes three actual citations for Canary brachiopods: Argyrotheca barrettiana (Davidson, 1866), Megerlia truncata (Linaeus 1767) and Pajaudina atlantica (Logan 1988). Also, the first two are first records for the archipelago. 4. This study use a criteria to resolve the controversy between the species P. atlantica and L. mediterranean. The morphological differences between them show that both species are not only different, but also belong to different genus. 5. The last fossil record in the Canary Islands of L. mediterranea is MIS 11 deposits from Piedra Alta, Lanzarote. Thereafter nothing is known about its presence in the archipielago. The present presence of P. atlantica suggests an affinity for ecological-climatic conditions different from today by L. mediterranea, which appear related to a warmer climate than the present judging by its accompanying fauna (Fig. 3; Tab. 1). 31 D. Eduardo González Álvarez , con DNI 45330221G, y direcciona efectos de notificación: Paseo de las Canteras, nº70 1er piso, autor del TFT denominado “Braquiópodos pliocenos pleistocenos y de las Canarias orientales con mención de los actuales” para obtener el título de máster dentro del programa de Oceanografía, hace constar: 1-.Para la elaboración de este trabajo se han realizado las sientes actividades: a) Estudios taxonómicos y sistemáticos sobre ejemplares fósiles y actuales. b) Estudios geológicos sobre los diferentes afloramientos fosilíferos dentro del marco geológico de los edificios insulares. c) Trabajo de campo, recolección de especímenes, catalogado y deposito en la colección de fósiles de la ULPGC. d) Fotografiado de especímenes fósiles. e) Estudios bibliográficos Estas actividades se han desarrollado a lo largo de los últimos 15 meses dentro el laboratorio de Paleontología, Paleoclimatología y Paleoceanografía del Departamento de Biología de la Facultad de Ciencias del Mar (ULPGC) 2-. Formación recibida. A lo largo de este periodo de trabajo, desde el Laboratorio de Paleontología de la ULPGC se ha pretendido dotar D. Eduardo González Álvarez de los conocimientos, aptitudes y recursos básicos para afrontar un estudio de tipo paleoclimático, paleoceanográfico y paleontológico. Estos recursos abarcan desde capacidades relacionadas con la taxonomía y la sistemática hasta tratamiento de la información y soportes y herramientas informáticas. 3-. La perspectiva de este trabajo es sentar las bases de colaboraciones futuras. Una primera derivada de este trabajo es la publicación y difusión de sus resultados dentro del marco de las revistas paleontológicas. Esto supone una serie de trabajos futuros que recalcan la integración dentro de este grupo de investigación. Durante este periodo la relación ha sido fluida, considerándose desde este grupo D. Eduardo González Álvarez como un activo más del mismo y que puede aportar conocimientos y trabajos en un campo de gran interés. Es necesario destacar que el grupo de paleontología presenta un 32 tamaño muy reducido, estando actualmente integrado por el profesor emérito Dr. Joaquín Meco Cabrera y el Dr. Juan Francisco Betancort Lozano como colaborador externo. La integración de un nuevo colaborador supone un refuerzo para las estructuras y proyectos de este grupo. 4-. Algunos aspectos positivos de la realización de un TFT de este tipo, supone la ampliación de conocimiento de aquel campo que a uno le inquiete y en el que se quiera profundizar. Algún aspecto negativo podría llegar a ser el hecho de rebuscar o indagar en algún tema o ‘subtema’ del que existe poca información. Gracias a la ayuda de internet, de numerosos trabajos publicados y de la formación recibida, hace posible que lleve a cabo el objetivo. 5-. La paleontología, así como sus campos más próximos como la paleoceanografía y la paleoclimatología, son ciencias que actualmente en las islas son de poca divulgación y conocimiento. Realizar este trabajo supone, no sólo un nivel formativo de un grado elevado, sino que también inicia a la persona a involucrarse con el medio ambiente, interpretar las formaciones geológicas que lo rodean, pensando y sobretodo captando la curiosidad de todo aquel que presta un mínimo de atención de esta extraordinaria ciencia. Para que conste afectos oportunos. En Las Palmas de Gran canaria, a 3 de diciembre de 2013 Eduardo González Álvarez