Mesozoic Ecosystems

2013.47 These maps (rectilinear projection) are from the PALEOMAP PaleoAtlas for ArcGIS (Scotese, 2013a-f).  This is a digital atlas of plate tectonic, paleogeographic, and paleoclimatic reconstructions designed for use with the GIS software, ArcMap (ESRI).  Table 1 lists the various types of maps that comprise the PALEOMAP PaleoAtlas.  The maps included in this folio are highlighted in bold text (Table 1).
The last map in each folio is a rectilinear graticule that can be overlain on the maps to provide a geographic reference frame.  A rectilinear projection was used because it can be easily georeferenced in ArcMap and transformed into a variety of other map projections.  The rectilinear, or plate caree map projection can also be directly “wrapped” onto a spherical projection, like the oneused by Google Earth. A set of Google Earth paleoglobes has made from the maps in this folio. These Google Earth paleoglobes can be downloaded at: www.globalgeology.com. 
If the map you need is missing, or if there doesn’t seem to be a map folio for the exact time interval of interest, please contact me (cscotese@gmail.com). Table 2 lists all the time intervals that comprise the PALEOMAP PaleoAtlas for ArcGIS. The PaleoAtlas contains one map for every stage in the Phanerozoic, as well as 6 maps for the late Precambrian.  Eventually, Map Folios, like this one, will be published for every time interval in the PALEOMAP PaleoAtlas.  The following section is a brief description of the maps that makeup the Map Folio.

This "flipbook", which illustrates the plate tectonic development of the continents and ocean basins during the past 750 million years, was assembled to commemorate the scientific career of Professor Rob van der Voo.  The flipbook consists of 34 plate tectonic reconstructions that map the past location of subduction zones (barbed lines), mid-ocean ridges, (dashed lines), and collision zones (marked x's). The tectonic reconstructions are based on the global plate tectonic model developed by the PALEOMAP Project. 
The latitudinal orientation of the continents is derived largely from paleomagnetic data collected by Professor van der Voo (xref).  Hot spots tracks and sea floor spreading isochrons (Seton et al., 2012) were used to constrain the longitudinal position of the continents back to  ~200 million years.  Plate tectonic reconstructions older than 200 million years are necessarily more speculative and have been derived by combining diverse lines of evidence from the tectonic histories of the continents (e.g., timing of continent-continent collisions or ages of rifting), the distribution of paleoclimatic indicators (i.e coals, tillites, salt deposits, and bauxites, see Boucot et al., 2013), and in some case, the biogeographic affinities of fossil faunas and floras.
Though a diverse data has been used to produce these reconstructions, this data, itself, is not  enough.  So much time has passed and so little direct evidence is preserved that guidance must also be sought from the "Rules of Plate Tectonics".
Plates do not move randomly but evolve in a manner that is consistent with the forces that drive them.  The principal driving forces are: slab pull, ridge push and trench rollback.  These forces shape the plates and provide important insights into how plate boundaries will evolve.  Simply said, plates will only move if they are pulled by a subducting slab or pushed by the forces exerted by a mature ridge system. The evolving plate boundaries have been drawn to follow this maxim.  It is also important to note that plate tectonics is a "catastrophic" system.  Though "slow and steady" is the general rule, once every hundred million years or so, a major plate tectonic reorganization occurs. These "plate tectonic catastrophes" most often occur when mid-ocean ridges are subducted or when major continents collide. (For a more complete listing of the "Rules of Plate Tectonics", the reader is referred to XXXXXX.
The first "continental drift" flipbook was pushed as an undergraduate research project (Scotese, 1974; 1975abc). Subsequent editions have followed (1976ab; 1978; 1979; 1980;  1990, 1991, 1997, 2004). A more complete description of the data and information that is used to produce the flipbooks can be found in Scotese (2004).  These maps could not have been produced without the GPlates plate modelling software and the tectonic data sets published by Dietmar Müller and his team at Earthbytes.
Special thanks to Maggie Geiger, and Robert and Jonathan Scotese for their help assembling this flipbook.

Time Scale
The age given next to each map represents age in millions of years.  The corresponding geological ages (Ogg et al., 2008)  are:
0    Modern World
20 Ma  Early Miocene
40 Ma  late Middle Eocene
60 Ma  Paleocene
80 Ma  Late Cretaceous - Campanian
100 Ma  Early Cretaceous - late Albian
120 Ma  Early Cretaceous - early Aptian
140 Ma  Early Cretaceous - Berriasian
160 Ma  Late Jurassic - Oxfordian
180 Ma  Early Jurassic - Toarcian
200 Ma  Triassic/Jurassic boundary
220 Ma  Late Triassic - Carnian
240 Ma  Middle Triassic - Anisian
260 Ma  Middle Permian - Capitanian
280 Ma  Early Permian - Artinskian
300 Ma  Late Pennsylvanian
320 Ma  Late Mississippian
340 Ma  Middle Mississippian
360 Ma  Devono-Carboniferous
380 Ma  Late Devonian - Frasnian
400 Ma  Early Devonian - Emsian
420 Ma  Late Silurian - Ludlow
440 Ma  Early Silurian - Llandovery
460 Ma  Middle Ordovician
480 Ma  Early Ordovician
500 Ma  Late Cambrian
520 Ma  Middle Cambrian
540 Ma  Cambrian-Precambrian
560 Ma  Neoproterozoic - lt. Ediacaran
600 Ma  Neoporterozoic - m. Ediacaran
630 Ma  Neoproterozoic - e. Ediacaran
660 Ma  Neoproterozoic - e. Ediacaran
690 Ma  Neoproterozoic - lt. Cryogenian
720 Ma  m. Cryogenian
750 Ma  m. Cryogenian


References Cited

Ogg, J., Ogg, G., and Gradstein, F.M., 2008. The Concise Geologic Time Scale, Cambridge University Press, 177 p.
Scotese, C.R. 1974. First Flip Book Images (from 35mm film from PLATO System), Unpublished.
Scotese, C.R., and Baker, D.W., 1975a. Continental drift reconstructions and animation, Journal of Geological Education, 23: 167-171.
Scotese, C.R., 1975b.  Continental Drift Flip Book, 1stedition.Chicago, Illinois. (single page version

Scotese, C.R., 1975c.  Continental Drift Flip Book, 1st edition. Chicago, Illinois. (double page version)
Scotese, C.R., 1976a. Continental
Drift “Flip Book”,  edition 1.5, Department of Geological Sciences, University of Illinois. ResearchGate  Academia
Scotese, C.R., 1976b. A continental drift “flip book", Computers & Geosciences, 2:113-116.
Scotese, C.R., and Ziegler, A.M., 1978. Paleozoic continental drift reconstructions and animation, American Geophysical Union, 1978 Spring Annual Meeting, Eos, v. 59. Issue 4, p. 263.
Scotese, C.R., 1979. Continental Drift (flip book), 2nd edition.
Scotese, C.R., Snelson, S.S., and Ross, W.C., 1980. A computer animation of continental drift, J. Geomag. Geoelectr., 32: suppl. III, 61-70.
Scotese, C.R., 1990. Atlas of Phanerozoic Plate Tectonic Reconstructions, PALEOMAP Progress 01-1090a, Department of Geology, University of Texas at Arlington, Texas, 57 pp.
Scotese, C.R., 1991. Continental Drift Flip Book, 4th edition, PALEOMAP Project, Arlington, TX, 49 pp.
Scotese, C.R., 1997.  Continental Drift Flip Book, 7th edition, PALEOMAP Project, Department of Geology, University of Texas at Arlington, Texas, 80 pp.

Scotese, 2004.
Seton et al., 2012.
Van der Voo,  R., 1993. Paleomagnetism of the Atlantic, Tethys, and Iapetus Oceans, Cambridge University Press, 411 p.

Belemnites (order Belemnitida), a very successful group of
Mesozoic cephalopods, provide an important clue for understanding Mesozoic marine ecosystems and the origin of modern cephalopods. Following current hypotheses, belemnites originated in the earliest Jurassic (Hettangian, 201.6–197 Ma) with very small forms. Accord- ing to this view their paleobiogeographic distribution was restricted to northern Europe until the Pliensbachian (190–183 Ma). The fossil record is, however, biased by the fact that all the previous studies on belemnites focused on Europe. Here we report two belemnite taxa from the Hettangian of Japan: a new species of the Sinobelemnitidae and a large taxon of the suborder Belemnitina. The Sinobelemnitidae, which may be included in the future in a new suborder, have also been recorded from the Triassic of China, specimens so far poorly under- stood. The presence of a very large rostrum attributed to the Belemni- tina suggests in addition that a diverse belemnite fauna evolved earlier than previously thought. Our new findings therefore (1) extend the origin of the belemnites back by ~33 m.y. into the Triassic, (2) suggest that this group did not necessarily originate in northern Europe, and (3) imply that belemnites survived the Triassic–Jurassic extinction, one of the five big mass extinctions in the Phanerozoic. Since belem- nites provided a considerable amount of food as prey, the origination of belemnites is probably an important event also for the evolution of their predators, such as marine reptiles and sharks.

The concept of ‘Gondwana’, an ancient Southern Hemisphere supercontinent, is firmly established in geological and biogeographical models of Earth history. The term Gondwana (Gondwanaland of some authors) derives from the recognition by workers at the Indian Geological Survey in the mid- to late 19th century of a distinctive sedimentary sequence preserved in east central India. This succession, now known to range in age from Permian to Cretaceous, is lithologically and palaeontologically similar to coeval non-marine sedimentary successions developed in most of the Southern Hemisphere continents suggesting former continuity of these landmasses. Palaeomagnetic data and tectonic reconstructions suggest that the main assembly of Gondwana took place around the beginning of the Palaeozoic in near-equatorial latitudes and that the supercontinent as a whole shifted into high southern latitudes, allowing widespread glaciation by the end of the Carboniferous. From Carboniferous to Cretaceous times the southern continents had broadly similar floras but some species-level provincialism is apparent at all times. The break-up of Gondwana initiated during the Jurassic (at about 180 million years ago) and this process is continuing. The earliest rifting (crustal attenuation) within the supercontinent initiated in the west (between South America and Africa) and in general terms the rifting pattern propagated eastward with major phases of continental fragmentation in the Early Cretaceous and Late Cretaceous to Paleogene. Gondwanan floras show radical turnovers near the end of the Carboniferous, end of the Permian and the end of the Triassic that appear to be unrelated to isolation or fragmentation of the supercontinent. Throughout the late Palaeozoic and Mesozoic the high-latitude southern floras maintained a distinctly different composition to the palaeoequatorial and boreal regions even though they remained in physical connection with Laurasia for much of this time. Gondwanan floras of the Jurassic and Early Cretaceous (times immediately preceding and during break-up) were dominated by araucarian and podocarp conifers and a range of enigmatic seed-fern groups. Angiosperms became established in the region as early as the Aptian (before the final break-up events) and steadily diversified during the Cretaceous, apparently at the expense of many seed-fern groups. Hypotheses invoking vicariance or long distance dispersal to account for the biogeographic patterns evident in the floras of Southern Hemisphere continents all rely on a firm understanding of the timing and sequence of Gondwanan continental breakup. This paper aims to summarise the current understanding of the geochronological framework of Gondwanan breakup against which these biogeographic models may be tested. Most phytogeographic studies deal with the extant, angiosperm-dominated floras of these landmasses. This paper also presents an overview of pre-Cenozoic, gymnosperm-dominated, floristic provincialism in Gondwana. It documents the broad succession of pre-angiosperm floras, highlights the distinctive elements of the Early Cretaceous Gondwanan floras immediately preceding the appearance of angiosperms and suggests that latitudinal controls strongly influenced the composition of Gondwanan floras through time even in the absence of marine barriers between Gondwana and the northern continents.

This "flipbook", which illustrates the plate tectonic development of the continents and ocean basins during the past 750 million years, was assembled to commemorate the scientific career of Professor Rob van der Voo.  The flipbook consists of 34 plate tectonic reconstructions that map the past location of subduction zones (barbed lines), mid-ocean ridges, (dashed lines), and collision zones (marked x's). The tectonic reconstructions are based on the global plate tectonic model developed by the PALEOMAP Project. 
The latitudinal orientation of the continents is derived largely from paleomagnetic data collected by Professor van der Voo (xref).  Hot spots tracks and sea floor spreading isochrons (Seton et al., 2012) were used to constrain the longitudinal position of the continents back to  ~200 million years.  Plate tectonic reconstructions older than 200 million years are necessarily more speculative and have been derived by combining diverse lines of evidence from the tectonic histories of the continents (e.g., timing of continent-continent collisions or ages of rifting), the distribution of paleoclimatic indicators (i.e coals, tillites, salt deposits, and bauxites, see Boucot et al., 2013), and in some case, the biogeographic affinities of fossil faunas and floras.
Though a diverse data has been used to produce these reconstructions, this data, itself, is not  enough.  So much time has passed and so little direct evidence is preserved that guidance must also be sought from the "Rules of Plate Tectonics".
Plates do not move randomly but evolve in a manner that is consistent with the forces that drive them.  The principal driving forces are: slab pull, ridge push and trench rollback.  These forces shape the plates and provide important insights into how plate boundaries will evolve.  Simply said, plates will only move if they are pulled by a subducting slab or pushed by the forces exerted by a mature ridge system. The evolving plate boundaries have been drawn to follow this maxim.  It is also important to note that plate tectonics is a "catastrophic" system.  Though "slow and steady" is the general rule, once every hundred million years or so, a major plate tectonic reorganization occurs. These "plate tectonic catastrophes" most often occur when mid-ocean ridges are subducted or when major continents collide. (For a more complete listing of the "Rules of Plate Tectonics", the reader is referred to XXXXXX.
The first "continental drift" flipbook was pushed as an undergraduate research project (Scotese, 1974; 1975abc). Subsequent editions have followed (1976ab; 1978; 1979; 1980;  1990, 1991, 1997, 2004). A more complete description of the data and information that is used to produce the flipbooks can be found in Scotese (2004).  These maps could not have been produced without the GPlates plate modelling software and the tectonic data sets published by Dietmar Müller and his team at Earthbytes.
Special thanks to Maggie Geiger, and Robert and Jonathan Scotese for their help assembling this flipbook.

Time Scale
The age given next to each map represents age in millions of years.  The corresponding geological ages (Ogg et al., 2008)  are:
0    Modern World
20 Ma  Early Miocene
40 Ma  late Middle Eocene
60 Ma  Paleocene
80 Ma  Late Cretaceous - Campanian
100 Ma  Early Cretaceous - late Albian
120 Ma  Early Cretaceous - early Aptian
140 Ma  Early Cretaceous - Berriasian
160 Ma  Late Jurassic - Oxfordian
180 Ma  Early Jurassic - Toarcian
200 Ma  Triassic/Jurassic boundary
220 Ma  Late Triassic - Carnian
240 Ma  Middle Triassic - Anisian
260 Ma  Middle Permian - Capitanian
280 Ma  Early Permian - Artinskian
300 Ma  Late Pennsylvanian
320 Ma  Late Mississippian
340 Ma  Middle Mississippian
360 Ma  Devono-Carboniferous
380 Ma  Late Devonian - Frasnian
400 Ma  Early Devonian - Emsian
420 Ma  Late Silurian - Ludlow
440 Ma  Early Silurian - Llandovery
460 Ma  Middle Ordovician
480 Ma  Early Ordovician
500 Ma  Late Cambrian
520 Ma  Middle Cambrian
540 Ma  Cambrian-Precambrian
560 Ma  Neoproterozoic - lt. Ediacaran
600 Ma  Neoporterozoic - m. Ediacaran
630 Ma  Neoproterozoic - e. Ediacaran
660 Ma  Neoproterozoic - e. Ediacaran
690 Ma  Neoproterozoic - lt. Cryogenian
720 Ma  m. Cryogenian
750 Ma  m. Cryogenian


References Cited

Ogg, J., Ogg, G., and Gradstein, F.M., 2008. The Concise Geologic Time Scale, Cambridge University Press, 177 p.
Scotese, C.R. 1974. First Flip Book Images (from 35mm film from PLATO System), Unpublished.
Scotese, C.R., and Baker, D.W., 1975a. Continental drift reconstructions and animation, Journal of Geological Education, 23: 167-171.
Scotese, C.R., 1975b.  Continental Drift Flip Book, 1stedition.Chicago, Illinois. (single page version

Scotese, C.R., 1975c.  Continental Drift Flip Book, 1st edition. Chicago, Illinois. (double page version)
Scotese, C.R., 1976a. Continental
Drift “Flip Book”,  edition 1.5, Department of Geological Sciences, University of Illinois. ResearchGate  Academia
Scotese, C.R., 1976b. A continental drift “flip book", Computers & Geosciences, 2:113-116.
Scotese, C.R., and Ziegler, A.M., 1978. Paleozoic continental drift reconstructions and animation, American Geophysical Union, 1978 Spring Annual Meeting, Eos, v. 59. Issue 4, p. 263.
Scotese, C.R., 1979. Continental Drift (flip book), 2nd edition.
Scotese, C.R., Snelson, S.S., and Ross, W.C., 1980. A computer animation of continental drift, J. Geomag. Geoelectr., 32: suppl. III, 61-70.
Scotese, C.R., 1990. Atlas of Phanerozoic Plate Tectonic Reconstructions, PALEOMAP Progress 01-1090a, Department of Geology, University of Texas at Arlington, Texas, 57 pp.
Scotese, C.R., 1991. Continental Drift Flip Book, 4th edition, PALEOMAP Project, Arlington, TX, 49 pp.
Scotese, C.R., 1997.  Continental Drift Flip Book, 7th edition, PALEOMAP Project, Department of Geology, University of Texas at Arlington, Texas, 80 pp.

Scotese, 2004.
Seton et al., 2012.
Van der Voo,  R., 1993. Paleomagnetism of the Atlantic, Tethys, and Iapetus Oceans, Cambridge University Press, 411 p.

Global Temperature Change in Deep Time Several recent studies have published estimates describing how global temperature has changed during the last 540 million years (Figure 1; Scotese et al., 2021). These temperature curves identify times when the Earth's global average temperature was much warmer than the presentday (hothouse intervals) and time intervals when, like the present-day, the Earth has been locked in a frigid "icehouse" world. Figure 2 is a "heat map" which highlights these hothouse and icehouse intervals (Scotese et al., 2021). Figure 1. Estimates of Global Average Temperature during the Phanerozoic

The prehistory of the Australian vegetation is summarized – from the earliest traces of life in the Precambrian to the events of the Cenozoic that shaped the continent’s modern flora. Australia’s oldest land plants appear in the Silurian with the rise of the lycophyte-dominated Baragwanathia flora. A succession of late Palaeozoic and Mesozoic pteridophyte- and gymnosperm-dominated floras followed, successive floras being punctuated by phases of major climate change and/or global mass-extinction events. For much of its Phenerozoic history, Australia has been part of the supercontinent Gondwana, thus it has shared broadly similar floras with the other Southern Hemisphere continents. The rise of the angiosperms in the Early Cretaceous was coincident with or slightly preceded the later stages of Gondwanan breakup. The modern angiosperm-dominated flora, therefore, developed during progressive isolation of Australia and its eventual collision with landmasses of southeast Asia. This history of isolation and amalgamation, together with the great climatic changes that have affected the continent over the past 100 million years, has set up intriguing scenarios for explaining the past and present distribution of a broad range of Australia’s plant taxa.

Cretaceous ichthyosaurs have typically been considered a small, homogeneous assemblage sharing a common Late Jurassic ancestor. Their low diversity and disparity have been interpreted as indicative of a decline leading to their Cenomanian extinction. We describe the first post-Triassic ichthyosaur from the Middle East, Malawania anachronus gen. et sp. nov. from the Early Cretaceous of Iraq, and re-evaluate the evolutionary history of parvipelvian ichthyosaurs via phylogenetic and cladogenesis rate analyses. Malawania represents a basal grade in thunnosaurian evolution that arose during a major Late Triassic radiation event and was previously thought to have gone extinct during the Early Jurassic. Its pectoral morphology appears surprisingly archaic, retaining a forefin architecture similar to that of its Early Jurassic relatives. After the initial latest Triassic radiation of early thunnosaurians, two subsequent large radiations produced lineages with Cretaceous representatives, but...

2013.51 These maps (rectilinear projection) are from the PALEOMAP PaleoAtlas for ArcGIS (Scotese, 2013a-f).  This is a digital atlas of plate tectonic, paleogeographic, and paleoclimatic reconstructions designed for use with the GIS software, ArcMap (ESRI).  Table 1 lists the various types of maps that comprise the PALEOMAP PaleoAtlas.  The maps included in this folio are highlighted in bold text (Table 1).
The last map in each folio is a rectilinear graticule that can be overlain on the maps to provide a geographic reference frame.  A rectilinear projection was used because it can be easily georeferenced in ArcMap and transformed into a variety of other map projections.  The rectilinear map projection can also be directly “wrapped” onto a spherical projection, like the oneused by Google Earth. A set of Google Earth paleoglobes has made from the maps in this folio. These Google Earth paleoglobes can be downloaded at: www.globalgeology.com. 
If the map you need is missing, or if there doesn’t seem to be a map folio for the exact time interval of interest, please contact me (cscotese@gmail.com). Table 2 lists all the time intervals that comprise the PALEOMAP PaleoAtlas for ArcGIS. The PaleoAtlas contains one map for every stage in the Phanerozoic, as well as 6 maps for the late Precambrian.  Eventually, Map Folios, like this one, will be published for every time interval in the PALEOMAP PaleoAtlas.  The following section is a brief description of the maps that makeup the Map Folio.

2013.50 These maps (rectilinear projection) are from the PALEOMAP PaleoAtlas for ArcGIS (Scotese, 2013a-f).  This is a digital atlas of plate tectonic, paleogeographic, and paleoclimatic reconstructions designed for use with the GIS software, ArcMap (ESRI).  Table 1 lists the various types of maps that comprise the PALEOMAP PaleoAtlas.  The maps included in this folio are highlighted in bold text (Table 1).
The last map in each folio is a rectilinear graticule that can be overlain on the maps to provide a geographic reference frame.  A rectilinear projection was used because it can be easily georeferenced in ArcMap and transformed into a variety of other map projections.  The rectilinear map projection can also be directly “wrapped” onto a spherical projection, like the oneused by Google Earth. A set of Google Earth paleoglobes has made from the maps in this folio. These Google Earth paleoglobes can be downloaded at: www.globalgeology.com. 
If the map you need is missing, or if there doesn’t seem to be a map folio for the exact time interval of interest, please contact me (cscotese@gmail.com). Table 2 lists all the time intervals that comprise the PALEOMAP PaleoAtlas for ArcGIS. The PaleoAtlas contains one map for every stage in the Phanerozoic, as well as 6 maps for the late Precambrian.  Eventually, Map Folios, like this one, will be published for every time interval in the PALEOMAP PaleoAtlas.  The following section is a brief description of the maps that makeup the Map Folio.

Until now dinosaur tracks from Switzerland were only known
from Triassic and Late Jurassic strata. We report here for the first
time the occurrence of ornithopod tracks from the Schrattenkalk
Formation (Late Aptian) from the Swiss Central Alps. The locality
is situated in an abandoned quarry on the shore of Lake
Lucerne close to the village of Beckenried.
The steeply inclined surface has more than 50 tracks ( in three
trackways) of ornithopod dinosaurs that are attributed to iguanodontids.
Three trackways can be followed for distances of 25 to
35 m. The lengths of the footprints (mean: 30 cm) point to animals
ranging in size of from 4 to 6 m, with estimated hip heights between
1.8 and 2 m (hip height 6 FL) and 1.4 to 1.7 m (hip height 5
FL). One of the trackways shows two succesive manus impressions,
indicating facultative quadrupedal gait.
The track bearing layer consists of shallow water micrites with
traces of emersion, and it is overlain by bioclastic grainstones.
Previously the Upper Schrattenkalk Member in the Helvetic
realm was thought to have formed on a large shelf far away from
any continents. The present discovery will shed new light on the
paleogeographic position of the Helvetic nappes.

A single rostrum of Cylindroteuthis (Cylindroteuthis) cf. theofilaktovi Nikitin recovered from the Late Bathonian－Early Callovian Kaizara Formation of the Tetori Group in Shimoyama, Kuzuryu area, Central Japan, is described for the first time in East Asia. This belemnite species has been previously known only from the Early Callovian of Central Ukraine in Eastern Europe. Since the family Cylindroteuthididae has been considered as the typical Boreal or northern element in the Jurassic belemnite paleobiogeographic studies, its occurrence in the Inner Zone (Japan Seaside) of Southwest Japan clearly indicates that Cylindroteuthis expanded its distribution to the mid-latitudes of the Northwest  Pacific  at  that  time.  This  expansion  possibly  corresponds  to  the  Early  Callovian  spread  of  boreal cylindroteuthids toward south into Europe in the Boreal-Atlantic seas. The occurrence of Cylindroteuthis  from the Kaizara Formation strongly suggests that a cooler current possibly from the Arctic reached the Tetori Basin in the Late Bathonian－Early Callovian time.

1999.02 The palaeopositions of India after its breakup from Gondwana and its subsequent northward journey during the Mesozoic and Early Palaeogene pose many plate tectonic and palaeobiogeographic riddles. Most reconstructions show peninsular India separating from Gondwana, and remaining an island continent for more than 100 million years until it collided with Asia. However, the lack of endemism among Indian Cretaceous terrestrial vertebrates is clearly inconsistent with the island continent hypothesis. A new model for the tectonic evolution of the Indian plate from its Pangean origin to the present day is proposed that is well constrained by geological and geophysical evidence. In this model, a previously unrecognized land area, called Greater Somalia, occupied the position between eastern Arabia and northwestern India. During the Late Jurassic, India rifted away from Greater Somalia. Throughout most of the Cretaceous India was separated from the rest of Gondwana but in the latest Cretaceous it reestablished contact with Africa through Greater Somalia. India maintained contact until the Eocene Period when it collided with Asia. Based on this plate tectonic model, 14 new paleogeographic maps are presented showing the evolution of the Indian plate from its Pangean origin to its final union with Asia. An area cladogram identifies the 11 nodes of hierarchial tectonic evolution of the Indian plate during the last 250 million years. A major question of Indian palaeobiogeography is how the terrestrial vertebrates such as dinosaurs responded to fragmentation of India from Gondwana. The similarities and differences between Indian vertebrates with those of other continental fragments provide an independent check for a number of key events during its tectonic evolution. Using the plate tectonic reconstructions as a guide, the distributions of dinosaurs and other vertebrates during the Mesozoic and Early Cenozoic are discussed. A close correspondence between the continental position of India and the distribution of vertebrates is generally observed. However, the Indian vertebrate fauna seems more closely related to Europe at the familial level to that of Africa during the Mesozoic. This disjunct endemism of fossil distribution pattern may reflect poor sampling from the intervening Africa. Whenever Indian vertebrate records are missing from certain geologic periods, their compositions are inferred from the contemporary animals in adajacent landmasses. The Late Triassic and Jurassic vertebrates of India are cosmopolitan in the Pangean world indicating various transcontinental migration routes. Four such dispersal routes are identified, northern, central, southern and western. During the mid-Cretaceous, India became isolated and these dispersal routes were closed. During the Late Cretaceous (approximately 70 Ma), the northern route across the Greater Somalia was reopened allowing immigration of dinosaurs and other vertebrates from Africa and Europe. This northern dispersal route explains for the first time why the Indian Maastrichtian vertebrates do not show any evidence of endemism. About 65 million years ago, the Shiva impact event at the Indo-Seychelles boundary and the Chicxulub impact in Mexico triggered a biotic catastrophe and led to the demise of dinosaurs and other organisms. Mammals rebounded from this catastrophe and became the dominant land vertebrates during the early Tertiary. Fossil evidence suggests that India made the initial contact with Asia during the Eocene and opened a new northeastern corridor for faunal interchange.

Giant Middle Coniacian to Lower Campanian Platyceramus Seitz is among the largest Cretaceous bivalves, commonly reaching an axial length of over 1 m, and occasionally over 2-3 m in size. The genus is characterized by its large size, very low convexity, normal inflation limited mostly to the umbonal area, and flattened flanks. It is especially common in moderately deep calcareous shale facies, as well as in chalks and limestones of the Niobrara Formation and equivalents. Preferred facies contain abundant pyrite, elevated total organic carbon (TOC), and very low biotic diversity. The genus maintains its giant size in these facies, and becomes more abundant. It clearly prefers dysoxic facies. As such, it probably is chemosymbiotic; photosymbiosis is almost ruled out because of inferred water depths of 200-350 m. It is also found more sparsely, and of smaller size, in oxygenated facies, including shoreface sandstone. The study area contains over 81 giant-sized Platyceramus platinus (Logan, 1898) on a single bedding plane; there are very few small ones. This allows spacing, orientation, and size analysis to be performed on an adult population.

Until 1960, the record of dinosaurs was rather poor in Switzerland. Between 1960 and 1980, several new localities with plateosaurid remains as well as prosauropod and theropod tracks were found in Late Triassic sabkha and floodplain environments.
The discovery of large surfaces with sauropod tracks in the Late Jurassic of the Jura Mountains in 1987 triggered a stream
of new data. More than 20 new localities with tracks from both sauropod and theropod dinosaurs in different stratigraphic levels
have been found since then. The latest discoveries include trackways of iguanodontids from the Early Cretaceous of the central Swiss Alps and a large Late Jurassic surface with trackways of small sauropods in the northernmost part of the Jura Mountains. The best skeletal record comes from the Late Triassic, with scattered data from the Late Jurassic. The track and trackway record appears to be best in the Late Jurassic.

This first overview of the bony fish record from the Jurassic and Cretaceous continental deposits of Thailand reveals a significant diversity, with 16 taxa in four formations (the Khlong Min, Phu Kradung, Sao Khua and Khok Kruat Fms). Four of these taxa have already been diagnosed and described, and a couple of others are sufficiently well preserved to be diagnosed in the future. The other taxa are represented at present by fragmentary and isolated remains. The highest diversity is observed among ‘semionotids’, which occur in the four formations. Sinamiids are represented by at least three taxa that occur only in the Sao Khua and the Khok Kruat Formations. Pycnodont fishes are known by rare and isolated dentitions and teeth in the Khlong Min and Sao Khua Formations, and lungfishes referred to Ferganoceratodus occur in the Khlong Min and the Phu Kradung Formations. The assemblages provide few palaeogeographical indications at present, except for evidence of relationships with China and Central Asia. However, it is expected than once the phylogenetic relationships of these taxa are resolved, we will be able to reconstruct precise palaeogeographical scenarios.

The discovery of the southernmost world record (49.5 S) of a Late Cretaceous insect fauna and plantinsect interactions is reported herein. The new locality is from the middle Cenomanian lacustrine deposits of the Mata Amarilla Formation belonging to the Austral foreland Basin, southwest Patagonia, Argentina. A first trip to the locality yielded few specimens of Coleoptera, among them an Archostemata: Cupedidae, and also a tiny specimen of Fulgoroidea: Perforissidae represented by Aonikenkissus zamunerae gen. et sp. nov. The Perforissidae were previously recorded from the Berriasian (?)-Barremian, Aptian, Albian, Turonian and Santonian in the Northern Hemisphere. The new species represents the first record of Perforissidae for South America and for the whole Southern Hemisphere. The new record suggests that the Perforissidae had a broader biogeographical distribution, and seem to have been cosmopolitan in the mid-Cretaceous. The Cupedidae reported herein is the first record for the Cenomanian and the first record of the genus Zygadenia in South America. Insect traces found in the same strata are made in an angiosperm palmatilobed leaf and correspond to a piercing and sucking type of damage. This type of damage is compared to recent stipples and to isolated piercings.

This paper investigates the exponential observer problem for the Lotka-Volterra (L-V) systems. We have applied Sundarapandian's theorem (2002) for nonlinear observer design to solve the problem of observer design problem for the L-V systems. The results obtained in this paper are applicable to solve the problem of nonlinear observer design problem for the L-V models of population ecology in the food webs. Two species L-V predator-prey models are studied and nonlinear observers are constructed by applying the design technique prescribed in Sundarapandian's theorem (2002). Numerical simulations are provided to describe the nonlinear observers for the L-V systems.

2016. The Late Triassic and Early Jurassic fissure faunas from Bristol and South Wales: Stratigraphy and setting. Palaeontologia Polonica 67, 257–287. The famous vertebrate-bearing fissures of the Bristol area in southwest England and in south Wales were traditionally referred to " upland " environmental settings, and assigned an overall time range of some 60 Myr; we reject both of these viewpoints. In terms of the environmental setting, based upon the evidence of palaeogeography, sediments, and fossils, we show that all the Triassic-aged fissures were near-coastal and embedded in karst formed on palaeo-islands in a subtropical archipelago. Further, the dates of these fissure fills in both regions do not span the Carnian to Rhaetian, as commonly supposed, but instead they are probably all Rhaetian. We update information on the Charles Moore Holwell " Microlestes " fissure assemblage and demonstrate that the marine fauna confirms a Rhaetian age. As proposed by previous authors , younger fissure fills around the St. Brides area of South Wales were also formed on an island, but during the Hettangian–Sinemurian. The youngest fissure deposit in the region is Pliensbachian. The age range of the fissures thus shrinks to c. 20 Myr, and the first episode of tetrapod fissure infilling shifts from the time of the Carnian " pluvial " episode, to the early Rhaetian, when western Europe was undergoing major rifting associated with the beginning of the opening of the North Atlantic, and when the Rhaetian sea flooded over landscapes that had long been purely terrestrial and arid. We recognise clear changes in the faunal composition of the terrestrial vertebrate biota from the early Rhaetian, dominated by reptile taxa, with some mammaliamorphs, that then declined rapidly in diversity before the Hettangian. This herpe-tofauna was followed by three faunal assemblages in the Early Jurassic of St. Brides which became increasingly diverse following the end-Triassic mass extinction; each had prominent mammaliamorphs as well as high numbers, but few species, of rhynchocephalians.