scholarly journals The Kvabebi Canidae record revisited (late Pliocene, Sighnaghi, eastern Georgia)

2017 ◽  
Vol 91 (6) ◽  
pp. 1258-1271 ◽  
Author(s):  
Lorenzo Rook ◽  
Saverio Bartolini Lucenti ◽  
Maia Bukhsianidze ◽  
David Lordkipanidze

AbstractUnlike the Asian and North American Pliocene record, fossil occurrences of Canidae in Europe (and Africa) are uncommon and fragmentary. The revision of canid material from the late Pliocene site of Kvabebi (eastern Georgia) revealed the contemporaneous occurrence of three different taxa: (1)Nyctereutes megamastoides(a derived species of the Eurasian Pliocene raccoon dog-like canids); (2)Vulpescf.V.alopecoides(representing the first occurrence of a member of the vulpine taxonV.alopecoides, a species that was the most widespread fox in the early Pleistocene in western Europe); and (3)Eucyonsp. The latter occurrence at Kvabebi completes our knowledge of the late Pliocene evolutionary history of the latest representatives of the genus in Western Europe and Central Asia. Our revision of Kvabebi canids registers a previously undocumented case of established niche partitioning among early Pliocene sympatric Canidae.

2012 ◽  
Vol 2012 ◽  
pp. 1-9 ◽  
Author(s):  
Masahiko Muraji ◽  
Norio Arakaki ◽  
Shigeo Tanizaki

The phylogenetic relationship, biogeography, and evolutionary history of closely related two firefly species,Curtos costipennisandC. okinawanus, distributed in the Ryukyu Islands of Japan were examined based on nucleotide sequences of mitochondrial (2.2 kb long) and nuclear (1.1-1.2 kb long) DNAs. In these analyses, individuals were divided among three genetically distinct local groups,C. costipennisin the Amami region,C. okinawanusin the Okinawa region, andC. costipennisin the Sakishima region. Their mtDNA sequences suggested that ancestralC. costipennispopulation was first separated between the Central and Southern Ryukyu areas, and the northern half was then subdivided betweenC. costipennisin the Amami andC. okinawanusin the Okinawa. The application of the molecular evolutionary clocks of coleopteran insects indicated that their vicariance occurred 1.0–1.4 million years ago, suggesting the influence of submergence and subdivision of a paleopeninsula extending between the Ryukyu Islands and continental China through Taiwan in the early Pleistocene.


2020 ◽  
Vol 3 (9) ◽  
pp. 250-253
Author(s):  
A.A.Erkuziev

Central Asia has played an important role in the political, economic and cultural relations of different nations and countries since ancient times as one of the centers of the world civilization. The Great Silk Road, which passed through this region, brought together the countries on the trade routes, the peoples living in them, and served to spread information about their traditions, lifestyles, location, historical events. These data, in turn, brought different peoples closer and served as the basis for the establishment of mutual economic and cultural relationships between them. One of the important scientific issues here is the study of the spread of information about the Central Asian region, where most of the Great Silk Road passed, to Western Europe through other countries.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Stefano Dominici ◽  
Mariagabriella Fornasiero ◽  
Luca Giusberti

AbstractBased on the fossil record, we explore the macroevolutionary relationship between species richness and gigantism in cowries (Cypraeidae), the best-studied family of gastropods, with a global diversity distribution that parallels that of tropical corals, mangroves and seagrasses. We introduce Vicetia bizzottoi sp. nov. based on a Priabonian fossil found in northeastern Italy, the largest documented cowrie found so far and the youngest of a lineage of Eocene Gisortiinae species. The Gisortiinae stratigraphic record in western Europe indicates that species selection favoured large size and armouring of the shell. Palaeoecology and per-stage species richness suggest that gigantism occurred in peripheral habitats with respect to diversity hotspots, where smaller species were favoured. The Eocene–Oligocene boundary was marked by a turnover and the Chattian global warming favoured small-sized species of derived clades. Species selection leading to gigantism is further documented in Miocene lineages of Zoila and Umbilia, in the southern hemisphere, two extant genera distributed at the periphery of modern diversity hotspots, suggesting that the negative relationship between size and diversity is a recurring pattern in the evolutionary history of cowries. This palaeontological evidence is projected onto the existing hypotheses that explain analogous biogeographic patterns in various other taxa. Likewise, body size-species richness negative relationship was possibly driven in cowries by physiological, ecological and life history constraints.


1992 ◽  
Vol 6 ◽  
pp. 43-43
Author(s):  
Ann F. Budd ◽  
Thomas A. Stemann ◽  
Kenneth G. Johnson

Study of the stratigraphic ranges of reef coral species in scattered sequences (Dominican Republic, Bahamas, Costa Rica, Jamaica, and Florida) suggests that a major episode of faunal turnover occurred in the Caribbean region between early Pliocene and mid Pleistocene time. In a data set composed of all reef corals except the families Mussidae and Oculinidae and the genera Cladocora and Madracis, approximately 90% of the Mio-Pliocene fauna, composed of as many as 65–70 species, became extinct during this time interval. Ten of 27 genera became extinct. Despite the high numbers of extinctions, the total number of species in the Caribbean reef coral fauna dropped only slightly over the time interval, due to similar numbers of originations and extinctions in the fauna. With one possible exception, new species arose in surviving genera, and no new genera formed.Although similar numbers of species became extinct within early Pliocene, late Pliocene, and early Pleistocene time units, shallow water communities experienced higher numbers of extinctions during the late Miocene and early Pliocene. Deeper water communities experienced higher numbers of extinctions during the late Pliocene and early Pleistocene. Species surviving the turnover episode occur in deeper water communities and belong predominantly to the family Agariciidae. Nearshore grass flat communities contain the highest number of early extinctions. No difference in extinction patterns could be detected between taxa which reproduce primarily by fragmentation and those that reproduce primarily by larval recruitment. Although originations appear evenly distributed among community types, a large number occur in Florida along the northern margin of faunal distribution.The increased extinctions in shallow water communities and increased originations in the north suggest that turnover occurred primarily in response to change in abiotic factors such as temperature and siltation, and not in response to species-area effects associated with sea level change.


Phytotaxa ◽  
2015 ◽  
Vol 211 (1) ◽  
pp. 1 ◽  
Author(s):  
JOEL CALVO ◽  
INÉS ÁLVAREZ ◽  
CARLOS AEDO

The complexity of the evolutionary history of Senecio is reflected in its conflicted taxonomy. Within this genus, Senecio section Crociseris (Compositae, Senecioneae), a group of perennial herbs distributed in Europe, western and Central Asia, and northwestern Africa, was not fully revised. A worldwide revision of this section recognizing 28 species and eight subspecies is presented here. The main morphological characters revealed as useful for distinguishing between species are the number and shape of supplementary and involucral bracts, synflorescence architecture, indumentum, and the shape and size of leaves and achenes. In this new taxonomic treatment S. provincialis and S. lagascanus have been segregated from S. doronicum, within which three subspecies are recognized (S. doronicum subsp. orientalis is validly published herein). On the other hand, S. ruthenensis from France and S. lusitanicus from Portugal have been synonymized to S. lagascanus, as well as S. ovatifolius, S. pisidicus, and S. tmoleus from Anatolia to S. kolenatianus, S. olympicus, and S. castagneanus respectively, S. bertramii from Lebanon to S. cilicius, and S. delbesianus from Syria to S. racemosus subsp. racemosus. Sixty eight names are lectotypified, the names S. barrelieri, S. pyrenaicus, and S. scopolii are neotypified, and one epitype is designated for the name S. perralderianus. Descriptions and distribution maps are provided for all the species included, as well as an identification key. Nine species are illustrated for the first time.


Author(s):  
Alan Cannell

Three genera of very large volant birds existed for most of the Pliocene: the Pelagornithidae seabirds; the large North American Teratornithidae and the stork Leptoptilos falconeri in Africa and Asia. All became extinct around 3 Ma. The reasons for their demise are puzzling, as the Pelagornithidae had a world-wide evolutionary history of more than 50 Ma, smaller teratorns were still extant in the Holocene and smaller stork species are still globally extant. Extant large birds have a common critical takeoff airspeed suggesting a biomechanical limit in terms of power, risk and launch speed, and simulations of the flight of these extinct species suggest that at 1 bar they would have exceeded this value. Estimates for the Late Pliocene atmospheric density are derived from marine and terrestrial isotopes as well as resin chemistry, both approaches suggesting a value of about 1.2 bar, which drops to present levels during the period 3.3 to 2.6 Ma, thus a loss in atmospheric density may have caused biomechanical and ecological stress contributing to their extinction and/or development of smaller forms. This hypothesis is examined in terms of a possible mechanism of atmospheric mass loss and how this would be seen in the geological record. At 1.2 bar all the extinct species present takeoff airspeeds similar to large extant volant birds and which match the expected power and kinetic energy levels.


2001 ◽  
Vol 56 (3) ◽  
pp. 411-418 ◽  
Author(s):  
Jordi Agustı́ ◽  
Oriol Oms ◽  
Eduard Remacha

AbstractCyclostratigraphic analysis of the Pliocene Zújar section (Guadix-Baza Basin, southeastern Spain) has enabled the recognition of a number of climatically forced cycles reflecting alternating dry and wet periods. Peaks of aridity are recorded at ca. 3.95, 3.55, 3.2, 2.8, and 1.8 myr B.P. The first dry period at about 4.0 myr B.P. corresponds to the early Ruscinian Mammal age, while the second arid interval at about 3.6 myr B.P. corresponds to the establishment of the Mediterranean double seasonality. The significant mammal turnover between the late Ruscinian and early Villanyian stages is placed between chron 2An.2n and the very base of chron 2An.1n, coincident with the dry phase recognized at about 3.2 myr B.P. The fourth aridity maximum at 2.8 myr B.P. roughly coincides with the Equus event in western Europe and is probably related to the beginning of the glacial–interglacial dynamics in the Northern Hemisphere. Finally, the last dry peak at about 1.8 myr B.P. is probably related to the set of mammalian events characterizing the transition from the late Pliocene faunas to those of the early Pleistocene.


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