1 http://www.youtube.com/watch?v=cjsReAgphEo
2
3
4
5
6
7
8 Clase GASTROPODA (Cámbrico?-Ordovícico-Actual). Asimétricos enrollados. Marinos y continentales. Grupo más abundante después de los insectos. Cabeza con ojos diferenciada, con sexos separados o hermafroditas. Larva trocófora o velíger ( directa). MORFOLOGÍA DE LA CONCHA Protoconcha y teleoconcha. Ultima vuelta. Ápice, helicono y abertura. Las vueltas y la sutura. Otros rasgos: columela, ombligo, canales sifonal y anal, labro… El opérculo. Orientación: Adapical, abapical, adaxial y abaxial. Modelos dextrorsos y sinistrorsos. Líneas de crecimiento. Tuberculos, cordones y costillas. MICROESTRUCTURA. Aragonítica con 3 o 4 capas. Crecimiento por acreción.
9 Esqueletos externos
10 Esqueletos internos (más extraños!)
11
12 MORFOLOGÍA DE LA CONCHA Protoconcha y teleoconcha. Ultima vuelta. Ápice, helicono y abertura. Las vueltas y la sutura. Otros rasgos: columela, ombligo, canales sifonal y anal, labro… El opérculo. Orientación: Adapical, abapical, adaxial y abaxial. Modelos dextrorsos y sinistrorsos. Líneas de crecimiento. Tuberculos, cordones y costillas. MICROESTRUCTURA. Aragonítica con 3 o 4 capas. Crecimiento por acreción.
13
14
15
16 Terminología para el enrollamiento
17
18
19
20 Terminología para las líneas de crecimiento
21 Tipos de protoconchas
22 Variables del arrollamiento Crecimiento por acreción
23 opérculo
24 Opérculos
25
26 Otros rasgos morfológicos
27 CLASIFICACIÓN Subclase PROSOBRANCHIA Cámbrico?-Actualidad. Con concha y torsión completa. Orden ARCHEOGASTROPODA (Cámbrico inf.-Actualidad) Orden MESOGASTROPODA (Ordovícico-Actualidad) Orden NEOGASTROPODA (Cretácico- Actualidad) Subclase OPISTOBRANCHIA Devónico-Actualidad. Marinos con pérdida total o parcial de la concha (Babosas marinas). Subclase PULMONATA Jurásico-Actualidad. Caracoles y babosas terrestres
28
29
30 Suclase Prosobranchia
31 Orden Archaeogastropoda
32
33
34 Orden Mesogastropoda
35
36
37 Mesogastropoda (perforaciones)
38 Orden Neogastropoda
39
40 Subclase Pulmonata
41
42 Subclase Opistobranchia
43 Nudibranquio
44 Nudibranquios (babosas de mar)
45
46
47
48 Subclase Opistobranchia Pterópodo This is a stereo pair and can be viewed in 3-D by crossing your eyes! You are aiming to have your left eye looking at the right hand image and your right eye looking at the left hand image. If you have difficulty seeing it in 3-D then follow these instructions
49
50
51 Subclase Opistobranchia Pterópodo
52
53
54 ECOLOGÍA Y PALEOECOLOGÍA Marinos o terrestres (agua dulce o salobre). Amplia batimetría. herbívoros, carnívoros, omnívoros, parásitos. Bentónicos o planctónicos. Espinados: substratos blandos (fijación) y defensa. Trazas bioerosivas de la rádula: Oichnus simplex (cónico), Oichnus parabolides (cónico) y Radulichnus (raspadores).
55 Modo de vida: empleo de la rádula
56
57
58 EVOLUCION. Derivarían de un ancestro con simetría bilateral, torciéndose para protegerse. Los primeros (Heliconella…del Cámbrico) mantienen simetría bilateral enrollada. Cámbrico sup. primeras conchas asimétricas (enrollamiento poco acusado: Archaeogastropoda). En el Carbonífero se diversifican, con un primer intento de colonización del continente. En el Carbonífero asociaciones vermetiformes, pseudoarrecifales. Los Pulmonata aparecen en el Jurásico
59 Estratigrafía Utilidad restringida
60 Ejemplo Strombus bubonius, S. Corunatus (fauna senegalesa) vs Arctica islandica en el Tirreniense del Mediterráneo
61 IBM
62 18 O (‰) HOLOCENE GLACIAL STAGES (MIS 2-3) GISP Meese et al. (1993)
63 Vostok
64 Entrada de fauna cálida (Senegalesa). Salida de fauna fría Salida de fauna cálida. Entrada de fauna fría (Nórdica)
65 INTERGLACIAL-SEA LEVEL AND NEOTECTONIC CONTROL: SPANISH COASTAL RECORD. C. Zazo Dpto Geología, Museo Nacional de Ciencias Naturales (CSIC), 28006, Madrid (España). The record of global-sea level can be interpreted from the study of ancient shorelines that have been tectonically uplifted. However the reconstruction of palaeo-sea level in some cases require several assumptions: constant uplift or the topographic position of sea level, for some interglacials using isotopic curve. Reconstruction of Quaternary sea-level changes and palaeo-shorelines in the littoral areas of Spain is very problematic due to a variety of factors. In first place, the laterally discontinuous nature of deposits in coastal areas due to neotectonic activity. Further and more important limitations drive from the inadequate temporal reach of dating methods coupled with errors inherent to the methods, such as late cementation of sediments containing shells used for study as no coral are avaiable in the area. No changes in fauna are recorded in the Peninsular coasts of Spain at the begining of the Pleistocene, hence the Pliocene warm fauna represented by Strombus coronatus surpassed the Plio-Pleistocene boundary. In contrast, a faunal renovation took place in the Balearic Islands, and the warm species characteristic of the Late Pliocene. (Strombus coronatus, Ostrea virleti, and Purpura gallica) were substituted by more temperate species (Ostrea cucullata, Purpura plessist). Most often sea-level changes are recorded by two marine terraces of Early Pleistocene age separated by prominent erosional surfaces, systems of alluvial fans, aeolian dunes, and karstic deposits. The uppermost of these two terraces is separated from the overlying basal Middle Pleistocene by either major scarp or increased alluvial-fan deposition. Two marine terraces have been found in the peninsular coastal areas of Cádiz, Málaga, Almería, Alicante that experience the highest rates of uplift. They are formed by several highstands with faunas similar to the present, and they occur separated by alluvial- fan deposits indicative of a drop in sea level. In the absence of radiometric data, correlation of these terraces with isotopic stages is only tentative. Considering the global behaviour of sea level, and field data, we suggest to correlate the lower, best represented terrace with isotopic stage 11, and the younger terrace with isotopic stage 9. The separation of these marine terraces and the more recent group of terraces is obvious from a morpho-stratigraphic point of view. Besides, the first immigration of the warm fauna derived from the equatorial Africa is recorded in some privileged areas of the littoral, such as the coast of Almería. The warm fauna entered the Mediterranean Sea via the Gibraltar Strait. It is characterised by Strombus bubonius and accompanying fauna commonly referred to as "Senegalese fauna". The oldest marine terrace containing this faunas has been dated (Th/U) as 180 Ka. The last interglacial is recorded in some privileged places by deposits of the three isotopic substages (5e, 5c, and 5a) yeiding Strombus bubonius. Two higstands are recognised during the substage 5e. The present sea level was reached at ca. 6500 yr BP.