Lower Pliocene horses from Black Hawk Ranch, Mount Diablo, California.

Mode of access: Internet.

The geological history and evolution of the horse / by Elmer S. Riggs, Assoc. Curator of Paleontology.

no.13(1932)

A new and primitive early Oligocene horse from Trans-Pecos Texas / Paul O. McGrew, Dept. of Geology, The University of Wyoming.

v.10:no.15(1953)

Evolution of the horse brain.

Bibliography: p. 170-174.

Evolution of the horse.

"Principal literature on the evolution of the horse": pt. 2, p. 64-[66]

Determination of ages and fossil Coleoptera fauna from eight sites in the London region

These data sets report the fossil beetle assemblages identified from the Mesolithic to Late Bronze Age at eight sites in the London region. All but one of the study sites are within 2 km of the modern course of the Thames. The sites produced 128 faunal assemblages that yielded 218 identified species in 41 families of Coleoptera (beetles).  Beetle faunas of Mesolithic age indicate extensive wetlands near the Thames, bordered by rich deciduous woodlands. The proportion of woodland species declined in the Neolithic, apparently because of the expansion of wetlands, rather than because of human activities. The Early Bronze Age faunas contained a greater proportion of coniferous woodland and aquatic (standing water) species. An increase in the dung beetle fauna indicates the presence of sheep, cattle and horses, and various beetles associated with crop lands demonstrate the local rise of agriculture, albeit several centuries after the beginnings of farming in other regions of Britain. Late Bronze Age faunas show the continued development of agriculture and animal husbandry along the lower Thames. About 33% of the total identified beetle fauna from the London area sites have limited modern distributions or are extinct in the U.K. Some of these species are associated with the dead wood found in primeval forests; others are wetland species whose habitat has been severely reduced in recent centuries. The third group is stream-dwelling beetles that require clean, clear waters and river bottoms.

Description of Micropygomyia brandaoi sp. n. (Diptera: Psychodidae: Phlebotominae), a fossil phlebotomine from the Dominican Republic

The description of Micropygomyia brandaoi, a new species of fossil phlebotomine sand fly, is based on one male specimen obtained from Dominican amber of the Miocene period (20 million years). In this new species, the fifth palpal segment is long, the coxite lacks a setal tuft and the style shows four well-developed spines. This set of characters allowed us to place the new species in the genus Micropygomyia Barretto.

Serological survey of Rickettsia sp. in horses and dogs in an non-endemic area in Brazil

Brazilian Spotted Fever (BSF) is a lethal rickettsiosis in humans caused by the bacteria Rickettsia rickettsii, and is endemic in some areas of Brazil. Horses and dogs are part of the disease's life cycle and they may also serve as sentinel animals in epidemiological studies. The first human BSF case in the State of Paraná was reported in 2005. The present study was conducted in the municipality of Almirante Tamandaré, where no previous case of BSF was reported. Serum samples were collected from 71 horses and 20 dogs from nine properties in the area. Ticks were also collected from these animals. All farmers completed a questionnaire about their knowledge of BSF and animal health management. Serum samples were analyzed by indirect immunofluorescent-antibody assay (IFA) using R. rickettsii and R. parkeri as antigens. Ticks were analyzed by PCR for Rickettsia sp., and all of them were PCR-negative. Six horses (8.45%) and 4 dogs (20%) were identified as seropositive. Farmers were not aware of the correlation between the presence of ticks and risk of BSF. Although a non-endemic area, Almirante Tamandaré is a vulnerable environment for BSF and effective tick control measures are required.

Exposure of free-ranging wild carnivores, horses and domestic dogs to Leptospira spp in the northern Pantanal, Brazil

Leptospirosis is a zoonotic disease affecting most mammals and is distributed throughout the world. Several species of domestic and wild animals may act as reservoirs for this disease. The purpose of this study was to assess the exposure of free-ranging wild carnivores, horses and domestic dogs on a private reserve located in the northern Pantanal (Brazil) and the surrounding areas to Leptospira spp from 2002-2006, 75 free-ranging wild carnivores were captured in the Pantanal and serum samples were collected. In addition, samples from 103 domestic dogs and 23 horses in the region were collected. Serum samples were tested for the presence of Leptospira antibodies using the microscopic agglutination test. Thirty-two wild carnivores (42.7%) were considered positive with titres > 100, and 18 domestic dogs (17.5%) and 20 horses (74.1%) were also found to be positive. Our study showed that horses, dogs and several species of free-ranging wild carnivores have been exposed to Leptospira spp in the Pantanal, suggesting that the peculiar characteristics of this biome, such as high temperatures and an extended period of flooding, may favour bacterial persistence and transmission. In this region, wild carnivores and horses seem to be important hosts for the epidemiology of Leptospira species.

Description of micropygomyia brandaoi sp. N. (diptera: psychodidae: phlebotominae), a fossil phlebotomine from the Dominican Republic

The description of Micropygomyia brandaoi, a new species of fossil phlebotomine sand fly, is based on one male specimen obtained from Dominican amber of the Miocene period (20 million years). In this new species, the fifth palpal segment is long, the coxite lacks a setal tuft and the style shows four well-developed spines. This set of characters allowed us to place the new species in the genus Micropygomyia Barretto

Review of American fossil phlebotominae (Diptera: Psychodidae) with a description of two new species

The objective of this study was to carry out a taxonomic review of fossil American phlebotomine sand flies and describe two new species found in amber in the Dominican Republic. The gonostyle of one of these, Micropygomyia dorafeliciangeliae nov. sp., (=Lutzomyia dorafeliciangeliae, species group oswaldoi), has five spines, similar to that of Micropygomyia paterna (Quate, 1963) (= Lutzomyia paterna, species group oswaldoi), but they may be distinguished by the alpha/gamma ratio, which is <1.0 in the new species and >1 in the latter. Pintomyia dominicana nov. sp. (=Lutzomyia dominicana, species group verrucarum) has four spines on the gonostyle and presents a long bristle on the apex of the paramere, which distinguishes it from the other fossil species. With the description of these two new species, a total of 14 species of the American fossil phlebotomine sand flies has been described, 10 of which belong to the genus Pintomyia. An identification key for male fossil species is presented

Fossil groups in the Millennium Simulation Evolution of the brightest galaxies

Aims. We create a catalogue of simulated fossil groups and study their properties, in particular the merging histories of their first-ranked galaxies. We compare the simulated fossil group properties with those of both simulated non-fossil and observed fossil groups. Methods. Using simulations and a mock galaxy catalogue, we searched for massive (>5 x 10(13) h(-1) M-circle dot) fossil groups in the Millennium Simulation Galaxy Catalogue. In addition, we attempted to identify observed fossil groups in the Sloan Digital Sky Survey Data Release 6 using identical selection criteria. Results. Our predictions on the basis of the simulation data are: (a) fossil groups comprise about 5.5% of the total population of groups/clusters with masses larger than 5 x 10(13) h(-1) M-circle dot. This fraction is consistent with the fraction of fossil groups identified in the SDSS, after all observational biases have been taken into account; (b) about 88% of the dominant central objects in fossil groups are elliptical galaxies that have a median R-band absolute magnitude of similar to-23.5-5 log h, which is typical of the observed fossil groups known in the literature; (c) first-ranked galaxies of systems with M > 5 x 10(13) h(-1) M-circle dot, regardless of whether they are either fossil or non-fossil, are mainly formed by gas-poor mergers; (d) although fossil groups, in general, assembled most of their virial masses at higher redshifts in comparison with non-fossil groups, first-ranked galaxies in fossil groups merged later, i.e. at lower redshifts, compared with their non-fossil-group counterparts. Conclusions. We therefore expect to observe a number of luminous galaxies in the centres of fossil groups that show signs of a recent major merger.

Fossil groups in the Millennium simulation Their environment and its evolution

Context. Fossil systems are defined to be X- ray bright galaxy groups ( or clusters) with a two- magnitude difference between their two brightest galaxies within half the projected virial radius, and represent an interesting extreme of the population of galaxy agglomerations. However, the physical conditions and processes leading to their formation are still poorly constrained. Aims. We compare the outskirts of fossil systems with that of normal groups to understand whether environmental conditions play a significant role in their formation. We study the groups of galaxies in both, numerical simulations and observations. Methods. We use a variety of statistical tools including the spatial cross- correlation function and the local density parameter Delta(5) to probe differences in the density and structure of the environments of "" normal"" and "" fossil"" systems in the Millennium simulation. Results. We find that the number density of galaxies surrounding fossil systems evolves from greater than that observed around normal systems at z = 0.69, to lower than the normal systems by z = 0. Both fossil and normal systems exhibit an increment in their otherwise radially declining local density measure (Delta(5)) at distances of order 2.5 r(vir) from the system centre. We show that this increment is more noticeable for fossil systems than normal systems and demonstrate that this difference is linked to the earlier formation epoch of fossil groups. Despite the importance of the assembly time, we show that the environment is different for fossil and non- fossil systems with similar masses and formation times along their evolution. We also confirm that the physical characteristics identified in the Millennium simulation can also be detected in SDSS observations. Conclusions. Our results confirm the commonly held belief that fossil systems assembled earlier than normal systems but also show that the surroundings of fossil groups could be responsible for the formation of their large magnitude gap.

REVISITING THE FOSSIL GROUP CANDIDATES UGC 842 AND NGC 6034

We present a new insight on NGC 6034 and UGC 842, two groups of galaxies previously reported in the literature as being fossil groups. The study is based on optical photometry and spectroscopy obtained with the CTIO Blanco telescope and Sloan Digital Sky Survey archival data. We find that NGC 6034 is embedded in a large structure, dominated by three rich clusters and other small groups. Its first and next four ranked galaxies have magnitude differences in the r band and projected distances which violate the optical criteria to classify it as a fossil group. We confirm that the UGC 842 group is a fossil group, but with about half the velocity dispersion that is reported in previous works. The velocity distribution of its galaxies reveals the existence of two structures in its line of sight, one with sigma(nu) similar to 223 km s(-1) and another with sigma(nu) similar to 235 km s(-1), with a difference in velocity of similar to 820 km s(-1). The main structure is dominated by passive galaxies, while these represent similar to 60% of the second structure. The X-ray temperature for the intragroup medium of a group with such a velocity dispersion is expected to be kT similar to 0.5-1 keV, against the observed value of kT similar to 1.9 keV reported in the literature. This result makes UGC 842 a special case among fossil groups because (1) it represents more likely the interaction between two small groups, which warms the intragroup medium and/or (2) it could constitute evidence that member galaxies lost energy in the process of spiraling toward the group center, and decreased the velocity dispersion of the system. As far as we know, UGC 842 is the first low-mass fossil group studied in detail.

A new fossil Adamussium (Bivalvia: Pectinidae) from Antarctica

Adamussium Jonkersi sp nov is described from the Late Oligocene Destruction Bay Formation Wrona Buttress area King George Island (South Shetlands) West Antarctica The unit characterized by volcanic sandstone is a shallow marine( succession deposited in a moderate- to high-energy environment The thin shelled pectinids collected from the lower part of the unit are preserved mostly as complete valves Shell thickness sculpture pattern and umbonal angle suggest a free-living inactive swimming life habit