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The lesson of the past is that when climate changes, species move. For instance, as the world emerged from the last ice age, temperatures rose dramatically across North America and Europe. Areas that had been frozen under solid ice—outside the niche of virtually any organism—suddenly thawed and supported rich assemblages of life. Less dramatic changes in the tropics led to different climates replacing one another in the space of a few 1000years. Many other climate shifts have occurred throughout the Earth’s history, changing the average climate of the planet and also the living conditions of every place on the planet.

Future human missions to the surface of the Moon and Mars will involve scientific exploration requiring new support tools to enable rapid and high quality science decision-making. Here, we describe the PANGAEA (Planetary ANalogue Geological and Astrobiological Exercise for Astronauts) Mineralogical Database developed by ESA (European Space Agency): a catalog of petrographic and spectroscopic information on all currently known minerals identified on the Moon, Mars, and associated with meteorites. The catalog also includes minerals found in the analog field sites used for ESA's geology and astrobiology training course PANGAEA, to broaden the database coverage. The Mineralogical Database is composed of the Summary Catalog of Planetary Analog Minerals and of the Spectral Archive and is freely available in the public repository of ESA PANGAEA. The Summary Catalog provides essential descriptive information for each mineral, including name (based on the International Mineralogical Association recommendation), chemical formula, mineral group, surface abundance on planetary bodies, geological significance in the context of planetary exploration, number of collected VNIR and Raman spectra, likelihood of detection using different spectral methods, and bibliographic references evidencing their detection in extraterrestrial or terrestrial analog environments. The Spectral Archive provides a standard library for planetary in-situ human and robotic exploration covering Visual-Near-Infrared reflective (VNIR) and Raman spectroscopy (Raman). To populate this library, we collected VNIR and Raman spectra for mineral entries in the Summary Catalog from open-access archives and analyzed them to select the ones with the best spectral features. We also supplemented this collection with our own bespoke measurements. Additionally, we compiled the chemical compositions for all the minerals based on their empirical formula, to allow identification using the measured abundances provided by LIBS and XRF analytical instruments. When integrated into an operational support system like ESA's Electronic Fieldbook (EFB) system, the Mineralogical Database can be used as a real-time and autonomous decision support tool for sampling operations on the Moon, Mars and during astronaut geological field training. It provides both robust spectral libraries to support mineral identification from instrument outputs, and relevant contextualized information on detected minerals.

Although Plate Tectonics cannot be effectively tested by palaeomagnetism in the Precambrian aeon due to the paucity of high precision poles spanning such a long time period, the possibility of Lid Tectonics is eminently testable because it seeks accordance of the wider dataset over prolonged intervals of time; deficiencies and complexities in the data merely contribute to dispersion. Accordance of palaeomagnetic poles across a quasi-integral continental crust for time periods of up to thousands of millions of years, together with recognition of very long intervals characterised by minimal polar motions (∼2.6–2.0, ∼1.5–1.25 and ∼0.75–0.6 Ga) has been used to demonstrate that Lid Tectonics dominated this aeon. The new PALEOMAGIA database is used to refine a model for the Precambrian lid incorporating a large quasi-integral crescentric core running from South-Central Africa through Laurentia to Siberia with peripheral cratons subject to reorganisation at ∼2.1, ∼1.6 and ∼1.1 Ga. The model explains low levels of tidal friction, reduced heat balance, unique petrologic and isotopic signatures, and the prolonged crustal stability of Earth's “Middle Age”, whilst density concentrations of the palaeomagnetic poles show that the centre of the continental lid was persistently focussed near Earth's rotation axis from ∼2.8 to 0.6 Ga. The exception was the ∼2.7–2.2 Ga interval defined by ∼90° polar movements which translated the periphery of the lid to the rotation pole for this quasi-static period, a time characterised by glaciation and low levels of magmatic activity; the ∼2.7 Ga shift correlates with key interval of mid-Archaean crustal growth to some 60–70% of the present volume and REE signatures whilst the ∼2.2 Ga shift correlates with the Lomagundi δ13 C and Great Oxygenation events. The palaeomagnetic signature of breakup of the lid at ∼0.6 Ga is recorded by the world-wide Ediacaran development of passive margins and associated environmental signatures of new ocean basins. This event defined the end of a dominant Lid Tectonic phase in the history of Earth's continental lithosphere recorded by the quasi-integral Precambrian supercontinent Palaeopangaea and the beginning of the comprehensive Plate Tectonics which has characterised the Phanerozoic aeon. Peripheral modifications to the lid achieved a symmetrical and hemispheric shape in Neoproterozoic times comparable to the familiar short-lived supercontinent (Neo)Pangaea (∼350–150 Ma) and this appears to be the sole supercontinent cycle recorded by the palaeomagnetic record. Prolonged integrity of a large continental nucleus accompanied by periodic readjustments of peripheral shields can reconcile divergent tectonic analyses of Precambrian times which on the one hand propose multiple Wilson Cycles to explain some signatures of Plate Tectonics, and alternative interpretations which consider that Plate Tectonics did not commence until the end of the Neoproterozoic.

Triassic rifting within western Pangaea was followed by almost-continuous subduction beneath the western margin of northern South America, which was disturbed during the collision and accretion of the Caribbean Large Igneous Province (CLIP) at 75 Ma. We review a very large quantity of geochronological, geochemical, isotopic, and thermochronological data that are used to develop a coherent geological model for the period spanning the latest Triassic to the Early Cretaceous, prior to the collision of the CLIP. These data have been collected over a trench (Pacific)-parallel distance of > 1500 km (Colombia and Ecuador), and reveal continuous subduction within a long-lived extensional regime. The Pacific active margin commenced at 209 Ma, and continued until 115 Ma above an east-dipping subduction zone that was rolling back, attenuating South America and forming new continental crust. Oceanward arc migration occurred during 194–193 Ma, and was pronounced 144–115 Ma, while the arc spanned a width of ~ 100 km during 193–144 Ma, during which time its location may have oscillated relative to the trench. Extension during 144–115 Ma was significant, and generated isotopically juvenile, transitional crust, which is best preserved in Ecuador (Peltetec crust), and significant intra-arc basins (the Salado Basin), while continental slivers were temporarily rifted from South America. The amount of Early Cretaceous extension increased from Colombia toward southern Ecuador, perhaps due to increasing amounts of slab retreat. The opening of the South Atlantic drove South America westwards, compressed the Pacific margin of northwestern South America at 115 Ma, closed the Salado Basin, redocked para-autochthonous blocks and obducted and exhumed a subduction zone, which is now exposed proximal to the Early Cretaceous South American margin.

The Triassic–Jurassic Extinction occurred about 201.3 million years ago about the time of the breakup of Pangaea.

The most severe biotic crisis on Earth history occurred during the Permian–Triassic (PT) transition around 252 Ma. Whereas in the marine realm such extinction event is well-constrained, in terrestrial settings it is still poorly known, mainly due to the lack of suitable complete sections. This is utterly the case along the Western Tethys region, located at Pangaea's equator, where terrestrial successions are typically build-up of red beds often characterised by a significant erosive gap at the base of the Triassic strata. Henceforth, documenting potentially complete terrestrial successions along the PT transition becomes fundamental. Here, we document the exceptional Coll de Terrers area from the Catalan Pyrenees (NE Iberian Peninsula), for which a multidisciplinary research is conducted along the PT transition. The red-bed succession, located in a long E-W extended narrow rift system known as Pyrenean Basin, resulted from a continuous sedimentary deposition evolving from meandering (lower Upper Red Unit) to playa-lake/ephemeral lacustrine (upper Upper Red Unit) and again to meandering settings (Buntsandstein facies). Sedimentary continuity is suggested by preliminary cyclostratigraphic analysis that warrants further analysis. Our combined sedimentological, mineralogical and geochemical data infer a humid-semiarid-humid climatic trend across the studied succession. The uppermost Permian strata, deposited under an orbitally controlled monsoonal regime, yields a relatively diverse ichnoassemblage mainly composed of tetrapod footprints and arthropod trace fossils. Such fossils indicate appropriate life conditions and water presence in levels that also display desiccation structures. These levels alternate with barren intervals formed under dry conditions, being thus indicative of strong seasonality. All these features are correlated with those reported elsewhere in Gondwana and Laurasia, and suggest that the Permian–Triassic boundary might be recorded somewhere around the Buntsandstein base. Consequently, Coll de Terrers and the whole Catalan Pyrenees become key regions to investigate in detail the Permian extinction event and the Triassic ecosystems recovery. © 2017 Elsevier B.V., E. Mujal obtained financial support from the PIF grant of the Geology Department at UAB, and from the Erasmus + program of the UAB performed at the Palaeontology Department from the Institut des Sciencies de l'Evolution (Université de Montpellier, France). E. Mujal received funding from the SYNTHESYS Project http://www.synthesys.info/ (FR-TAF-3621, FR-TAF-4808) which is financed by European Community Research Infrastructure Action under the FP7 “Capacities” Program. J. Fortuny acknowledges the support of the postdoc grant “Beatriu de Pinós” 2014 – BP-A 00048 from the Generalitat de Catalunya as well as from the Spanish Ministerio de Economía, Industria y Competitividad and the European Regional Development Fund of the European Union (MINECO/FEDER EU, project CGL2014-54373-P). J. Pérez-Cano acknowledges the support from the Spanish Ministerio de Economía, Industria y Competitividad (FPI grants BES-2016-076469). This work received support from CERCA programme at Institut Català de Paleontologia (ICP) and from the projects “Vertebrats del Permià i el Triàsic de Catalunya i el seu context geològic” and “Evolució dels ecosistemes amb faunes de vertebrats del Permià i el Triàsic de Catalunya” (ref. 2014/100606), based at ICP and financially supported by the Departament de Cultura (Generalitat de Catalunya).

The Triassic, which occurred from 252 to 201 million years ago, was a period when the continental grouping was at its most intact. Almost all of the current continents were grouped within Pangaea and surrounded by Panthalassa, an immense ocean. Pangaea was largely divided by an ocean open to the east that separated Laurasia in the north from Gondwana in the south. This ocean was composed of two distinct ocean floors, the Paleo-Tethys in the north and the Neo-Tethys in the south, which were separated by the Cimmerian continents. The Triassic saw the closure of the Paleo-Tethys by subduction under Laurasia as well as the opening of the Neo-Tethys. At the end of the Triassic, the Central Atlantic magmatic province marked the beginning of the opening of the central Atlantic. The global climate was hot and very continental due to the particular layout of the land masses. The approximate geographic location of the main sites containing freshwater fishes is presented.

This paper describes the Upper Triassic to Middle Jurassic evaporites of the Saharan Platform in eastern Algeria, Tunisia, and western Libya. This evaporitic sequence is a key element of the North African petroleum systems forming a regional seal to hydrocarbon reservoirs of the Palaeozoic and Triassic. The succession spans the time interval Norian to Bajocian and comprises three sequences. Sequence 1 (mid-Norian to late Sinemurian) consists of five evaporitic cycles dominated by mudstone and halite, which represent the main salt deposits of the Berkine Basin. At this time the Berkine-Ghadames basin was a restricted evaporitic basin with a barrier to the north (Medenine-Jifarah High) separating it from a peri-Tethys area. These evaporites were formed by the marine flooding of the eastern margin of Pangaea. Sequence 2 (Pliensbachian) is a nonevaporitic interlude represented by the basin-wide development of a carbonate platform (B Marker). This is the product of relative sea level rise and tectonic adjustment associated with the emplacement of magmatic rocks of the Central Atlantic Magmatic Province (CAMP) and reflects the opening of an Atlantic gateway to the peri-Tethys. Sequence 3 (late Pliensbachian-late Bajocian) comprises five cycles that are predominantly mudstones, fine-grained carbonates, anhydrites, and halite deposited as global sea level rose. They show cyclostratigraphic changes on a variety of scales, which probably relate to astronomical fluctuations. The depositional style contrasts with Sequence 1, the presence of carbonates, occasional patch reefs, and sabkha-type anhydrites indicating a marine carbonate-evaporite ramp setting. Similar thickness variations to those observed in Sequence 1 continued through Sequence 3 and reflect the ongoing influence of differential subsidence along basement lineaments. Sequence 3 salt deposits are restricted to Algeria and progressive westward and southward onlap resulted in Liassic salt being deposited on north-south basement ridges. A number of factors controlled the development of this evaporite basin. These include late Triassic sea level rise and flooding of a subsea level fluvio-lacustrine basin, combined with globally warm climatic conditions, ongoing break-up of Pangaea and the emplacement of the CAMP. The evaporite deposits contain the records of these major global tectonic and climatic changes at the Triassic-Jurassic boundary.

Transcontinental correlation of European carbonate systems that developed during the onset of the Mesozoic breakup of Pangaea remains difficult due to pronounced lateral facies variations and in many cases facies-dependent fossil groups used for biostratigraphic dating and correlation. In addition, radiometric dating of ash layers associated with Middle Triassic carbonate successions in Europe is limited to certain areas and times of volcanic activity. Thus, Middle Triassic correlation schemes of the Tethyan and Peri-Tethyan realm—a highly dynamic area in terms of plate reorganization and related development of early Mesozoic epeiric seas—need further refinement using new correlation tools. Here, we highlight the Europe-wide occurrence of a silica-rich horizon at the Anisian–Ladinian boundary as a potential trans-European correlation horizon. Chert layers and nodules form in different depositional settings, under different conditions and within different facies, thus being well suited for interregional correlation. However, the processes leading to chert formation in Middle Triassic shallow-marine carbonate deposits are still under discussion and require further research in order to make this prominent feature a powerful correlation tool.

We present revised plate tectonic and paleogeographic reconstructions of the western Tethyan region for the time interval between the late Permian (~ 260 Ma) and the early Jurassic (200 Ma), which encompasses the time of the breakup of Pangaea. Three global paleogeographic reconstructions are presented for the latest Permian (Lopingian, ~ 260 Ma), early Late Triassic (Carnian, 230 Ma), and earliest Jurassic (200 Ma). We also present three regional paleogeographic maps of the same time intervals for the Western Tethys region. These regional paleogeographic maps are based on a rigorous self-consistent plate kinematics model and are accompanied by a reconstruction of paleoenvironmental features, such as lowlands, highlands, and salt basins, as well as the distribution of lithofacies (mud, silt, sand, and carbonates). The reconstructions presented here differ from previous plate reconstructions of Western Tethys. The plate model presented here includes a revised compilation of tectonic elements compatible with the observed distribution of subducted lithosphere in the present-day Mediterranean region.

The oldest rocks in Libya have been dated at almost 3 billion years. Since then the territory of Libya has successively formed part of Rodinia, Pannotia, Gondwana, Pangaea and Africa. It has a long and complex history, but at its most fundamental it is located within the Saharan metacraton, in which ancient cratons, Proterozoic orogenic belts and accreted island arcs were remobilised during the Pan-African orogeny. These basement rocks are overlain by variable thicknesses of Phanerozoic sediments. During the course of its long history plate movements have transported the territory of Libya from a position close to the equator in the Neoproterozoic, southwards across the south polar region in the Ordovician, then northwards, crossing the equator during the Triassic to its present location 30° north of the equator. Libya exhibits evidence of all four of the great orogenic events of earth history: the Pan-African, Caledonian, Hercynian and Alpine.

The first vertebrates date back more than 500 million years ago, during the Cambrian explosion, and had cartilaginous internal skeletons, no functional jaws, and bony external shields. True fish with bony internal skeletons evolved more than 450 million years ago in the Ordovician and diversified further in the Devonian. Vertebrates invaded land at about 350 million years ago, giving rise to the many forms we know from extant lineages and extinct fossils. Because of the timing of their initial diversification on land, terrestrial vertebrate diversification was initially impacted by the break of Pangaea, Laurasia, and Gondwana, a process that resulted in isolation and unique early radiations of land vertebrates on individual landmasses. At the same time, clues indicating intercontinental dispersal and subsequent diversification became apparent in the fossil record; they are also now apparent in today’s time-calibrated phylogenetic analyses of extant taxa. With increased fragmentation of landmasses, isolated islands, archipelagos, and island chains became influential for determining the biogeographic patterns of terrestrial vertebrates. Insular habitat systems have disproportionately contributed to the evolutionary process of diversification of land animals. Many of the Earth’s most spectacular land vertebrate evolutionary radiations are attributed to the unique evolutionary opportunity presented by island archipelagos.

Until recently the climate of the Early–Middle Triassic at low latitudes was broadly considered as generally temperate-warm with no major climate oscillations. This work examines the climate of this period through a detailed study of the sedimentary, plant, soil and mineral records of continental rocks (Buntsandstein facies) in eastern Iberian basins. Our findings indicate temporal climate variations for these near equator (10°–14°N) regions and unveil the significance of such variations in the southern Laurasian domain. The climate of Iberia's Early Triassic was mainly dominated by alternating brief (< 0.4 ma) arid and semi-arid climate periods, with two main arid periods documented at the end of the Smithian and middle Spathian. However, an initial short subhumid to semi-arid period was also observed in the late Spathian. Remarkably, this latter period appears just after an unconformity related to the tectonically induced Hardegsen Event in western Europe. It is also of interest that this short subhumid climate period is concurrent with the beginning of faunal and floral recovery in the basins examined. The Early Triassic ended again with a short very arid period. Although the beginning of the Anisian (Aegean) was represented by alternating arid and semi-arid to subhumid intervals, during the Bithynian and Pelsonian clearly wetter climates are recorded by the succession consisting of alternating semi-arid to semi-humid intervals. This general tendency was interrupted by three short but marked intervals, two humid intervals in the late Bithynian, and one arid period near the Bithynian/Pelsonian boundary. Iberia was crossed by prominent irregular highs separating marked corridors or isolated areas. This palaeogeography, prevailing since Variscan tectonics, clearly conditioned dominant climates and their geographical distribution. No clear climate belts developed in these conditions. However, isolated internal climate zones separated by elevated areas are identified. This palaeogeographic configuration and the low latitudinal position of Iberia determined central Iberia highs in the southernmost border of Laurasia, beyond which more humid conditions clearly extended towards the equator reaching the present-day Moroccan Meseta and Argana Basin.

The Late Cisuralian is known as a time of increasing aridity, compared to the Late Pennsylvanian–Early Cisuralian. Although several studies highlighted this trend at low latitudes of Western Pangaea, little is known from Central Pangaea environments. The discovery of new fossiliferous horizons in the Late Cisuralian Tregiovo Formation (Northern Italy), allowed a new palaeoenvironmental study based on facies analysis, ichnology, palaeobotany, plant–insect interaction and palynology. Three facies associations were identified (A–C), and correspond to floodplain lake, ephemeral lacustrine and distal alluvial fan environments, respectively. The tetrapod ichnoassociation is more diverse than previously known, including abundant diapsid and non-diapsid reptile tracks and rarer temnospondyl amphibian tracks. Plant fossils are characterized by a predominance of hinterland taxa (conifers), hygrophytic plants are present as well. The sporomorph association is dominated by miospores of Cordaitales, Voltziales, and Peltaspermales while trilete lycopsid and fern miospores are rare which corresponds well with the macroflora. Invertebrate trace fossils and feeding traces on plant fossils are described for the first time from the Tregiovo Basin suggesting transitional, low energy environments, and a relatively low level of herbivory, respectively. This study evidences the development in the Tregiovo Basin of a wet-and-dry (probably seasonal) climate, which became drier between facies associations A–B. This environment constitutes an important reference since few data are known to infer the Late Cisuralian climatic conditions of Central Pangaea.

The Cretaceous System/Period is the last major subdivision of Mesozoic time. Established by JJ d'Omalius d'Halloy in 1822, the Cretaceous and was divided into Upper and Lower series/epochs by WD Conybeare and William Phillips that same year. Cretaceous rocks are currently assigned to 12 stage/age-level subdivisions, the combination of which represent an interval estimated to lie between 145.0 and 66.0 Ma. This is the longest single system/period of the Phanerozoic and Cretaceous rocks are found on all continents. Palaeogeographically, the Cretaceous represents the time during which Pangaea continued to fragment and continental plates began to move into their current positions. Prominent tectonic features of Cretaceous time include the rifting of Laurasia to form the northern and southern embayments of the proto-Atlantic Ocean, the joining of these embayments into a single north–south-trending Atlantic Ocean Basin, and the rifting of the southern supercontinent of Gondwana into South America, Antarctica, India, and Australia.

Models of mass extinctions caused by greenhouse warming depend on the ability of warming to affect the oxygenation of the ocean, either through slowing circulation or changes in biological productivity and the organic carbon budget. Opal Creek, Alberta, Canada is a biostratigraphically continuous Permian–Triassic Boundary (PTB) section deposited in deep water on an outer shelf setting in the vast and understudied Panthalassic Ocean, along the western margin of Pangaea. The latest-Permian extinction is here represented as the disappearance of the previously dominant benthic fauna (siliceous sponges). On the basis of nitrogen and reduced sulfur isotopes as well as productivity-sensitive trace elements, the Middle Permian at Opal Creek is interpreted as a highly productive coastal upwelling zone where vigorous denitrification and sulfate reduction occurred in a mid-water oxygen minimum. Similar conditions appear to have continued into the latest Permian until the onset of a euxinic episode represented by a discrete pyrite bed and several trace element indicators of high productivity. This euxinic pulse is followed by the extinction of benthic fauna and a shift in nitrogen and sulfur isotopes to more normal marine values, suggesting the cessation of coastal upwelling and the consequent weakening of the mid-water oxygen minimum. The Lower Triassic appears to be a dysoxic, relatively unproductive environment with a bottom water oxygen minimum. Rhenium–osmium isotope systematics show a minimum of radiogenic Os near the main extinction event, which may be due to volcanic input, and increasingly radiogenic values approaching the PTB, possibly due to increased continental erosion. The Opal Creek system demonstrates that, while the biogeochemical crisis in the latest Permian was capable of impacting the coastal upwelling modality of ocean circulation, a transient increase in productivity likely drove the system toward euxinia and, ultimately, extinction.

From the late Triassic onwards, while dinosaurs were dominating the land and pterosaurs were taking to the air, a revolution in marine life was taking place beneath the waves. As the supercontinent of Pangaea began to break up, sea levels rose, and vast areas of low-lying land were flooded by epicontinental seas which supported coral reefs teeming with life. In such environments, full of potential prey, marine reptiles quickly diversified and dominated the seas; they included ichthyosaurs, plesiosaurs, crocodiles, and turtles.

During the early part of the Cretaceous Period the supercontinent of Pangaea continued to break up, owing to movements deep in the Earth's mantle. Initially North America and Europe pulled apart, opening up the North Atlantic Ocean, and by the end of the early Cretaceous, South America and Africa also began to cleave apart to form the South Atlantic. Meanwhile the Tethys Ocean extended westwards so that the northern continents were divided from those in the south. This loss of land bridges and migration routes led to a diversification of animal and plant life on separated continents.

Asia, the world's largest continent, lies entirely in the Northern Hemisphere extending from the Equator to the Arctic Circle. The continent is unique in its inland waters because it has the world's highest mountain peaks and the lowest place, most rainy and most arid areas, and both the hottest and coldest places. Geologically, Asian continent represents the fusion of the Pangaea and the Gondwanaland. Most of the Middle East, Central Asia, Mongolia, western China (including Tibet), and western part of the Indian subcontinent constituting more than one third of the Asian continent are semi-arid to hyperarid, and either too hot or too cold. More than half of the world's human population resides in Asia. The natural lakes have originated in diverse ways, the vast majority of them being from various kinds of tectonic, volcanic, and glacial activities often interacting with each other. The world's oldest (L. Baikal, ∼25 Ma), deepest (L. Baikal, 1671 m), and largest (L. Caspian, >371 000 km2) lakes occur in Asia. Asia also has the lakes lying at the highest (>6000 m) and lowest (−400 m) places on the Earth. The majority of the lakes in arid regions are saline to hypersaline. Lakes formed by aeolian processes and the meteoritic impacts are also common in Asia. Numerous fluvial (riverine) lakes of all sizes and depths occur in the basins of many large rivers that flow in all directions from the central Asian highlands and the mighty Himalayan ranges. The monsoonal climate with highly variable and seasonal precipitation has necessitated the construction of innumerable reservoirs throughout the south and southeast Asia and in China for drinking water supplies and irrigation. In recent decades, very large multipurpose reservoirs have been constructed throughout the continent for hydropower generation and flood control, besides irrigation.

This chapter focuses on ecological determinants of present-day distributions of amphibians and reptiles. It discusses how the history of the Earth's continents has affected amphibian and reptile distributions. Finally, it shows several phylogeography studies to show how the combined use of well-supported phylogenetic hypotheses and geological-fossil data is rapidly improving the understanding of the history of patterns of distribution and diversification in amphibians and reptiles. Most studies of island biogeography reveal a close association between the number of species and island size, if everything else is equal. Distance of islands from mainland habitats also affects number of species. Island biogeography has much wider application because habitats distributed across the Earth are patchy, and each patch can effectively be considered an island. The theory of island biogeography can be applied to ecological questions, particularly in landscape ecology and conservation biology. Ecological biogeography emphasizes the overall structure of communities across space and has resulted in descriptions of biomes, biogeographic realms, and other ecologically based categories. Historical biogeography focuses on the relationships and origins of taxa, emphasizing the phylogenetic affinities of the species and how those tie in with the history of distributional patterns. In addition to the historical approaches to the study of distributions, present-day animal and plant distributions can be described on the basis of overall structure of plant communities relative to climate.

A series of paleogeographic time-slices showing step-by-step convergence of Gondwana, Baltica, Avalonia, Laurentia, and intervening terranes in the Early Ordovician–Early Permian time span has been made utilizing apparent polar wander paths (APWPs), constructed on the basis of paleoclimatic (Gondwana) and paleomagnetic (Baltica, Avalonia, and Laurentia) dataset. A destination assembly for the wandering continents was Pangea, reconstructed in so-called A configuration. A modeling of paleogeographic evolution was made assuming actualistic distribution of paleoclimatic belts, present-day lithospheric plate velocities, and the validity of the geocentric axial dipole magnetic field in the Paleozoic. Ockham's razor has been applied in determination of a longitudinal component of an oceanic width between Gondwana and Laurussia. A drift history of some intervening terranes, incorporated into Caledono–Variscan fold belt of Europe is also shown. The terranes are positioned according to paleomagnetic and geologic information, supplemented by some outcomes of paleontological studies. However, the paleogeography of some Cadomian blocks as those incorporated into the Armorica accreted superterrane, Alpine basement or the Silesian Massif is speculative and have had to be interpolated between better time-and-space constrained positions. Combined with available geological data, reconstructions performed in this study leads to the conclusion that the Rheic Ocean could have been up to 2000–2500 km wide domain during the Early Paleozoic. In turn, the Silurian/Devonian Massif Central-Moldanubian Ocean featured variable geometry, depending upon continuosly changing configuration of the Gondwana-derived terranes. At their waning stages, the Rheic and the Massif Central-Moldanubian Oceans were the second-order domains within a 1500–2000 km wide Theic-ProtoTethys Ocean, separating Laurussia and Gondwana during the Devonian. A sense of the relative movements of the continents confirms the view that the convergence of Gondwana with respect to Laurussia was generally dextrally oblique in the Late Paleozoic. Although paleoclimatic data controlling paleogeographic position of Gondwana represent different types of information than these for Laurentia/Baltica, an inferred story of the Gondwana and Laurussia convergence and Pangea assembly may incorporate a wide spectrum of geological observations.

A palynoflorule from the Moroccan Meseta north of Khenifra closely matches fossil pollen assemblages from the European Autunian Series, as described by Daubinger (1974) and from the Pictou Group of Nova Scotia (Barss and Haquebard, 1967). The age of these assemblages is latest Carboniferous to earliest Permian A second palynoflorule from the Central High Atlas south of Marrakech is of mid-Carnian age based upon the concurrence of age-diagnostic pollen species that have been reported from the Swiss and English middle Keuper, type Carnian of Austria, and North American Triassic beds in Virginia, North Carolina, Pennsylvania, New Jersey, Texas, New Mexico, and Arizona. These age determinations serve to document a large-scale unconformity that encompasses virtually all the Permo-Triassic on the Moroccan Meseta and High Atlas. This episode of pronounced crustal thinning preceded Triassic rifting, and ultimately led to the fragmentation of Pangaea.

The tectonic pattern of Britain and Ireland mainly dates from the Caledonian Orogeny due to closure of the late Neoproterozoic to Silurian Iapetus Ocean that separated the Laurentian continent from Baltica and Avalonia. The Early to Mid-Ordovician collision between Laurentia and an intra-oceanic volcanic arc resulted in the Grampian orogenic event. Eastern Avalonia joined Baltica during the latest Ordovician before early Silurian “hard” collision of Baltica with Laurentia that resulted in the Scandian orogenic event. In contrast, the late Silurian “soft” collision of Eastern Avalonia with Laurentia was not associated with major shortening. Instead sinistral, orogen-parallel motion between Laurentia and Baltica–Avalonia gave strike-slip displacement along major faults in northern Britain into the Early Devonian. During later Early Devonian times, widespread Acadian deformation in Eastern Avalonia probably resulted from the collision of Armorica and Iberia with the southern margin of Avalonia. In late Carboniferous time, the major Gondwana continent collided with the assembled northern continents, closing the intervening Rheic Ocean and causing the Variscan Orogen. This belt runs west–east across southern Ireland, Wales and England. In Mesozoic time the Pangaea supercontinent began to break up so that extensional basins formed across the British–Irish region. Most basins follow the pre-existing Caledonian and Variscan template. The end of basin extension in mid-Cretaceous time was followed by thermal subsidence, itself terminated in two areas by Paleogene events; plume-related uplift and magmatism in north and west Britain and Ireland and weak shortening across southern England related to the Pyrenean orogeny to the south.