Sunday, 24 July 2016

Pristimantis prometeii: A new species of Rain Frog from the cloud forests of El Oro in southern Ecuador.

The tropical forests of Central and South America are home to almost half of the known species of Amphibians, and since about a quarter of these species have been described in the past decade, this is likely to be a severe under-estimation of the true diversity of Amphibians in these forests. The largest group of Amphibians in these American tropical forests is the Brachycephaloidea, a group of Frogs with an entirely terrestrial life-cycle, laying eggs in moist habitats, which develop directly into small Froglets and missing out on the Tadpole stage altogether. About half of the described Brachycephaloidians are included in the most specieous genus of terrestrial vertebrates known, Pristimantis, members of which are commonly known as Rain Frogs, which contains almost 500 species.

In a paper published in the journal ZooKeys on 21 July 2016, Paul Székely of the Faculty of Natural and Agricultural Sciences at Ovidius University Constanţa and the Departamento de Ciencias Naturales at the Universidad Técnica Particular de Loja, Dan Cogălniceanu, also of the Faculty of Natural and Agricultural Sciences at Ovidius University Constanţa and of the Universidad Nacional de Loja, Diana Székely, again of the Faculty of Natural and Agricultural Sciences at Ovidius University Constanţa and the Departamento de Ciencias Naturales at the Universidad Técnica Particular de Loja, and of the Laboratory of Fish and Amphibian Ethology at the University of Liège, abd Nadia Páez and Santiago Ron of the Museo de Zoología at the Pontificia Universidad Católica del Ecuador, describe a new species of Robber Frog from the cloud forests of El Oro in southern Ecuador.

The new species is named Pristimantis prometeii, which refers to the Prometeo program of Secretaría de Educación Superior, Ciencia, Tecnología e Innovación of the Republic of Ecuador, through which Dan Cogălniceanu and Paul Székely received funding for their research in southern Ecuador. The Frogs are brown or green in colour with variable blotchy markings. Adult females reach 29.9–37.6 mm in length, males 20.4–24.9 mm.

Pristimantis prometeii, female specimen. Székely et al. (2016).

The species was found at three locations in the Reserva Buenaventura, at altitudes of between 878 and 1082 m. The species was observed in September in 2014 and 2015, generally after rain at night, when they could be found on leaves close to the forest floor (10-100 cm above the ground).

See also...

http://sciencythoughts.blogspot.co.uk/2015/11/eleutherodactylus-beguei-new-species-of.htmlEleutherodactylus beguei: A new species of Grass Frog from Guantánamo Province in southeast Cuba.                                          Small Grass Frogs are found across Cuba. Until 2012 these were all placed within a single species, Eleutherodactylus varleyi, but it was...
http://sciencythoughts.blogspot.co.uk/2015/04/robber-frogs-from-mountains-of-western.htmlRobber Frogs from the mountains of western Mexico.                                                                         Robber Frogs of the genus Eleutherodactylus are found from Texas to Guatemala and Belize and across the islands of the Caribbean. The genus was formerly the most specious of any genus of Vertebrate Animals (i.e. it contained more species than any other...
http://sciencythoughts.blogspot.co.uk/2014/08/a-new-cryptic-species-of-microhylid.htmlA new cryptic species of Microhylid Frog from Espírito Santo State, Brazil.                      Cryptic species are species which resemble one-another physically, and which cannot generally be separated using traditional taxonomic methodology, but which are nevertheless genetically and reproductively isolated. Genetic studies of many groups...
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Using a hypothetical ninth planet to explain the obliquity of the Solar System.

The major planets of our Solar System (Mercury, Venus, Earth, Mars, Jupiter, Saturn, Uranus and Neptune) all orbit within a single plain, sometimes called the Plain of the Solar System, with none of the planets varying from this by more than a degree. This is consistent with the theory that the Sun and Planets formed from an initial disk of swirling matter within a larger nebulae. However the Sun itself is angled to this plain, rotating on a plane of axis six degrees out from that of the Plane of the Solar System. This is insignificant compared to some of the highly tilted orbits seen in exoplanets, with some known planetary systems hosting planets with orbits that vary by tens of degrees, but does require an explanation if our model of how the Solar System (and other stellar systems) formed is correct.

Several theories have previously been proposed to explain this obliquity. The young Sun could have been tilted from the plane by the activity of the stellar magnetosphere and its interactions with the protoplanetary disk, or the Sun could have started out with an asymetric distribution of mass in its core, leading to it acquiring an axial tilt. Alternatively the disc could have been tilted by a close encounter with another star or even a dense molecular cloud early in its life, or the Sun could have started out with a companion star that has subsequently been lost. However while all of these theories work on paper, there is no real way of either proving or disproving any of them at this time, which leaves us no closer to finding a solution to the mystery.

On 20 January 2016 Division of Geological and Planetary Sciences at the California Institute of Technology published a paper in The Astronomical Journal which suggested the observed clustering of objects in the Kuiper Belt might be attributable to the shepherding actions of a previously unknown planet with a mass 5-20 times that of the Earth and a highly eccentric orbit with an average distance from the Sun of 250 AU (i.e. 250 times the average distance between the Earth and the Sun).

Top view of the Keplerian trajectories of all bodies with a > 250AU as well as dynamically stable objects with a > 150AU. The two thin purple orbits correspond to stable bodies within the 150 < a < 250AU range. For each object, the directions of the angular momentum and Runge-Lenz (eccentricity) vectors are additionally shown. Batygin & Brown (2016).

In a paper published on the online arXiv database at Cornell University Library on 14 July 2016, Elizabeth Bailey of the Division of Geological and Planetary Sciences at the California Institute of Technology, along with Konstantin Batygin and Michael Brown, discus the posibility that such a hypothetical planet, refered to as Planet Nine, might be responsible for the obliquity of the Solar System.

It theory a large enough body in the Kuiper belt could exert sufficiant gravitational pull on the planets to alter their orbits, yet the planets would remain in the same plane of orbit as they gravitational pull they exert upon oneanother is greater than that exerted upon them by Planet 9. Importantly, unlike the other theories currently available, the existance of Planet nine, plus its size and orbit are potentially testable (since if such a planet exists it must be possible to directly observe it, even if this is not possible with current technology).

To this end Bailey et al. constructed a model of the Solar System, imputting the known parameters of the discovered planets, and assuming that they started orbitting in the same plane as the Solar Equator, plus a variety of different Planet 9s, in different orbits and having masses equivalent to 10, 15 ans 20 times that of the Earth.

Parameters of Planet Nine required to excite a spin-orbit misalignment of i = 6 deg over the lifetime of the solar system, from an initially aligned state. Contours in a9-e9 space denote i9, required to match the present-day solar obliquity. Contour labels are quoted in degrees. The left, middle, and right panels correspond to m9 = 10; 15, and 20mEarth respectively. Due to independent constraints stemming from the dynamical state of the distant Kuiper belt, only orbits that fall in the 150 < q9 < 350AU range are considered. The portion of parameter space where a solar obliquity of i = 6 deg cannot be attained are obscured with a light-brown shade. Bailey et al. (2016).


Bailey et al. found that a planet of any of the sizes modelled could potentially have caused the current obliquity of the Solar System over the 4.5 billion years of its existance, but (importantly) in order to do this it would need to be in an orbit much closer to that of the Plane of the Solar System then is predicted for the current orbit of Planet 9, based upon its influence on bodies in the Kuiper Belt. However this does not preclude the possibility that such a planer could be responsible for the obliquity, as it's orbit would also be effected by the gravitational interplay with the other planets of the Solar System (which are expected to have a much greater mass), potentially pushing it into a new orbit.

See also...

http://sciencythoughts.blogspot.co.uk/2016/05/hubble-space-telescope-discovers-moon.htmlHubble Space Telescope discovers a moon orbiting the Dwarf Planet Makemake. Makemake is the largest known body in the Kuiper Belt and the second-brightest Trans-Neptunian Object (after Pluto). It has a very bright albedo (it reflects a lot of light), with a surface apparently covered by...
http://sciencythoughts.blogspot.co.uk/2016/03/seasonal-exospheres-detected-on-dione.htmlSeasonal exospheres detected on Dione and Rhea.                                                    Exospheres are gas envelopes around planets and moons too thin to be considered true atmospheres. Unlike atmospheres, the gasses in exospheres are not thought to interact with one another, rather individual molecules are thought to be lost from the body's surface, spend some time in the exosphere, then either be lost into space or resettle onto the surface...
http://sciencythoughts.blogspot.co.uk/2016/03/sputnik-planum-apparently-young-feature.htmlSputnik Planum: An apparently young feature on the surface of Pluto.                                 Pluto was the first known and is one of the largest bodies in the Kuiper Belt, a field of Dwarf Planets and smaller bodies beyond Neptune which are thought to have been beyond the zone of true-planet formation, and therefore to reflect the nature of the early Solar System. In July 2015 the New Horizons spacecraft flew past Pluto, making a detailed survey of the surface...
 
 
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Asteroid 2016 OA passes the Earth.

Asteroid 2016 OA passed by the Earth at a distance of 1 734 000 km (4.50 times the average distance between the Earth and the Moon, or 1.16% of the average distance between the Earth and the Sun), at about 8.15 am GMT on Monday 18 July 2016. There was no danger of the asteroid hitting us, though had it done so it would have presented no threat. 2016 OA has an estimated equivalent diameter of 16-49 m (i.e. it is estimated that a spherical object with the same volume would be 16-49 m in diameter), and an object of this size would be expected to explode in an airburst (an explosion caused by superheating from friction with the Earth's atmosphere, which is greater than that caused by simply falling, due to the orbital momentum of the asteroid) in the atmosphere between 25 and 9 km above the ground, with only fragmentary material reaching the Earth's surface.
 
 The calculated orbit of 2016 OAJPL Small Body Database.

2016 OA was discovered on 16 July 2016 (two days before its closest approach to the Earth) by the University of Arizona's Mt. Lemmon Survey at the Steward Observatory on Mount Lemmon in the Catalina Mountains north of Tucson. The designation 2016 OA implies that the asteroid was the first object (object A) discovered in the second half of July 2016 (period 2016 O).
 
2016 OA has a 1401 day orbital period and an eccentric orbit tilted at an angle of 1.09° to the plane of the Solar System that takes it from 0.75 AU from the Sun (i.e. 75% of the average distance at which the Earth orbits the Sun and slightly outside the orbit of Venus) to 4.15 AU from the Sun (i.e. 4.15% of the average distance at which the Earth orbits the Sun, considerably outside orbit of the planet Mars). It is therefore classed as an Apollo Group Asteroid (an asteroid that is on average further from the Sun than the Earth, but which does get closer).
 
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http://sciencythoughts.blogspot.co.uk/2016/07/asteroid-2016-nk22-passes-earth.htmlAsteroid 2016 NK22 passes the Earth.   Asteroid 2016 NK22 passed by the Earth at a distance of 264 500 km (0.69 times the average distance between the Earth and the Moon, or 0.18% of the average distance between the Earth and the Sun), at about 1.15 pm GMT on Monday 11 July 2016. There...
http://sciencythoughts.blogspot.co.uk/2016/07/asteroid-2016-na-passes-earth.htmlAsteroid 2016 NA passes the Earth.      Asteroid 2016 NA passed by the Earth at a distance of 483 100 km (1.26 times the average distance between the Earth and the Moon, or 0.32% of the average distance between the Earth and the Sun), slightly before 5.00 pm GMT on Friday 1 July 2016...
http://sciencythoughts.blogspot.co.uk/2016/06/asteroid-2004-kh17-passes-earth.htmlAsteroid 2004 KH17 passes the Earth.   Asteroid 2004 KH17 passed by the Earth at a distance of 16 990 000 km (30.2 times the average distance between the Earth and the Moon, or 11.4% of the average distance between the Earth and the Sun), slightly before 0.20 am GMT on Thursday 2 June...
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Jellyfish damage to farmed Salmon on the West Coast of Ireland.

Farmed Salmon are raised within caged enclosures in marine embayments, spending their entire lives within a limited area, unlike wild Salmon which roam over vast areas during their life-cycles, spending parts of their lives in marine environments and parts in freshwater. This makes farmed Salmon vulnerable to a variety of environmental threats that wild Salmon are able to avoid. One such threat is damage by Jellyfish swarms, which drift in vast numbers on the ocean currents, and which can cause significant damage when they encounter farmed Salmon, with smaller Jellyfish able to pass through cage meshes directly and adult specimens being broken up by the meshes, killing the Jellyfish but creating body fragments with still active stinging cells which could enter the cages. In one notorious case in 2007 a swarn of Mauve Stinger Jellyfish, Pelagia noctiluca, wiped out the entire stock of a Salmon farm in Northern Ireland, about 250 000 Fish.

In a paper published in the Journal of Fish Disease in January 2016, Mar Marcos-L opez, Susie Mitchell and Hamish Roger of Vet-Aqua International in Oranmore, County Galway, Ireland, descibe the results of a study of Jellyfish damage to farmed Salmon on the West Coast of Ireland in 2013.

The most abundant swarming Jellyfish seen on thw West Coast during the study peroid was the Mauve Stinger, however unidentified species of Phialella and Muggiaea were also recorded. Mauve Stingers are an entirely free-living species, unlike many Jellyfish which have a bottom-dwelling atteched polyp stage, enabling swarms drifting on ocean currents to continuously add to their own numbers (species with an attached polyp stage typically swarm for a season, then produce an overwintering polyp stage). They are found in vast numbers in all warm and temperate seas and oceans, though in seasonal climates they do die off in winter, so the biggest swarms are found in autumn and late summer, when seasonal storms often push them onto shores.

In 2013 Mauve Stingers swarms were reported at Salmon farms from August to November on the West Coast of both Northern Ireland and the Republic of Ireland, resulting in mortality rates among caged Salmon of up to 70%. Examination of both dead and live Salmon revealed numerous skin lessons, with Fish sufferning from respiratory distress (a syptom of Jellyfish venom), loss of apatite, apathy and increased jumping.

Numerous Pelagia noctiluca jellyfish inside marine Atlantic Salmon pen. Pete McDonagh in Marcos-L opez et al. (2016).

Many of the lessons caused by Jellyfish stings were found to be infected with a filamentous Bacterium, Tenacibaculum sp., which appeared to colonize necrotic Jellyfish filaments; these Bacteria are known to be carried by living Jellyfish, suggesting the infection was brought with the swarm, and was not just an opportunistic action by an organism living free in the water. The Salmon farmers responded to these infections by raising the levels of anti-biotics administered to the Fish.

See also...

http://sciencythoughts.blogspot.co.uk/2014/06/a-new-species-of-jellyfish-from-north.htmlA new species of Jellyfish from the North Adriatic Sea. While instantly familiar and biologically simple, Jellyfish (Scyphozoa) are still in many ways poorly understood, with frequently poorly understood life-cycles and population structures, leading to unexpected shifts in population and sudden blooms of large numbers of Jellyfish, which can impact on commercial...
http://sciencythoughts.blogspot.co.uk/2013/10/jellyfish-force-closure-of-swedish.htmlJellyfish force closure of Swedish nuclear power plant.                                   The Oskarshamn Nuclear Power Plant in Kalmar County on Sweden's southeast coast was forced to...
http://sciencythoughts.blogspot.co.uk/2013/06/the-mysterious-ebb-and-flow-of.htmlThe mysterious ebb and flow of Jellyfish populations.                                               Many scientists and conservationists are worried about the state of the world's oceans. Many important marine ecosystems are known to be under stress: once prolific fisheries have collapsed; dead


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Saturday, 23 July 2016

Evidence of cannibalism in a Neanderthal population from the Late Pleistocene of Belgium.

In the century and a half since the discovery of the first Neanderthal remains traces of the group have been found across much of Europe and Western Asia. During this time there has been a great deal of speculation about the cognitive abilities of Neanderthals, particularly since the discovery of examples of ritual behaviour otherwise known only in Modern Humans, such as burying their dead, making jewelry and even using cosmetics. One behavioural trait occasionally reported in Neanderthals, is cannibalism (eating members of their own species), interpreted as having taken place at sites where Neanderthals show signs of having been modified in ways that suggest butchery. However while this behaviour has been suggested for Neanderthals on several occasions, the evidence is very limited, comprising largely of isolated finds from different localities, making it difficult to interpret as a consistent and planned activity, and in many cases difficult to assert that the butchering was carried out by Neanderthals themselves, and not early Modern Humans.

In a paper published in the journal Scientific Reports on 6 July 2016, a team of scientists led by Hélène Rougier of the Department of Anthropology at California State University, Northridge describe a series of Neanderthal remains from the Late Pleistocene Goyet Cave System in Belgium.

The Goyet Cave System was first excavated in 1868, with further  excavations in the early twentieth century and 1990s. Archaeological material comes from a number of layers in the Troisième Caverne (Third Cave), which has produced artifacts assigned to the Mousterian (a culture considered to exclusively Neanderthal), the Lincombian-Ranisian-Jerzmanowician (which may have been made by late Neanderthals or early Modern Humans), the Aurignacian, the Gravettian and the Magdalenian (Modern Human cultures from the Late Pleistocene and Early Holocene). Early excavations at the site were not carried out to modern standards, but it is thought that the Mousterian comes from several layers and indicates several separate periods of occupation.

As well as artifacts Goyet has yielded 283 bones and teeth identified as Human, including 96 bones and three teeth considered to be of Neanderthal origin, as well as a large volume of bones and teeth of non-Human origin. Rouger et al. carried out carbon dating on 10 of these Neanderthal specimens, yielding dates of 40-45 000 years before the present, relatively young by Neanderthal standards, but to old to be of Modern Human origin. A DNA analysis was also carried out of fifteen sets of the remains, the results of which suggests that the individuals were closely related to other late Pleistocene Neanderthals, including those from the Neander Valley in Germany, El Sidrón in Spain and Vindija in Croatia.

Neandertal remains from the Troisième caverne of Goyet (Belgium). * Designates the specimens that have been directly dated. Scale bar is 3 cm. Rouger et al. (2016).

All of the Neanderthal remains were highly fragmentary (no complete bones were present), with the majority coming from either long limb bones or the cranium. Of the 96 bone fragments, 47 could be refitted to other fragments, suggesting they represent a fairly low number of individuals. Roughly half of the Neanderthal bones showed signs of butchering with stone tools, including marks consistent with defleshing (cutting meat from the skeleton) and dismemberment (cutting the skeleton into smaller, more manageable pieces). Four of the bones, a femur and three tibias, show signs of having been used to retouch stone tools.

Retouching marks (b1,b2) and cutmarks (c1,c2) present on the Goyet Neandertal bones (example of femur III). (a) femur III in anterior view; (b1,c1) close-up photos; (b2,c2) images obtained using a minidome. Rouger et al. (2016).

Since these skeletons date from considerably before the occupation of northern Europe by Modern Humans, the possibility of butchery by Modern Humans can be discounted, providing clear evidence for the practise of cannibalism amongst a Late Pleistocene Neanderthal population in northern Europe for the first time. The bones appear to have been cut while the bodies were still fresh, suggesting that the people making the cuts would have known that they were dismembering other people rather than animals, but whether this was a ritualised activity, or an activity carried out for strictly pragmatic reasons cannot be asserted upon the available evidence.

Four other sites within 250 km of Goyet have yielded Neanderthal remains, none of which provide any evidence of funeral behaviour. Walou Cave and Trou de l’Abîme in Belgium have produced only loose teeth while Feldhofer in Germany has produced a series of Neanderthal remains associated with Keilmesser technologies; an older Neanderthal technology not found at Goyet, which suggests an age of over 70 000 years. Interestingly one of the Feldhofer skeletons has marks interpreted as cut marks, though this skeleton has the long bones of its limbs intact, suggesting that butchery was not the motive for these cuts. The final site, Spy in Belgium, has produced items of the Lincombian-Ranisian-Jerzmanowician technology, along with two adult skeletons. However the more intact of these shows signs of having been buried in a contracted position, and the remains appear to have been buried rapidly, suggesting that they may have died and been burried as a result of some natural event, without any input from either other Neanderthals or early Modern Humans.

See also...

http://sciencythoughts.blogspot.co.uk/2015/09/neanderthal-dna-from-37-000-42-000.htmlNeanderthal DNA from a 37 000-42 000 modern Human jaw from Romania.     Neanderthals first appeared in Europe around 300 000 years ago and were replaced by anatomically modern Humans between 45 000 and 35 000 years ago. Genetic studies if modern Human populations show that almost all non-Africans have traces


Early and Middle Pleistocene Human remains are extremely rare in northern Europe, having to date...
Ritual or symbolic behavior is generally taken as a sign of cognitive levels comparable to those of modern humans by palaeoanthropologists studying ancient...
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Saskatchewan city forced to cut water intake by oil spill.

The city of North Battleford in Saskatchewan has been forced to stop pumping water from the North Saskatchewan River after oil from a burst pipeline reached the river on Friday 22 July 2016. The city is understood to have around three days of water reserves, after which it will be forced to fall back upon a groundwater treatment plant. The pipeline, which is operated by Husky Energy is understood to have burst on Thursday 21 July, releasing between 200 000 and 250 000 liters of a crude oil mixture (crude oil plus added lighter oils used to help the oil flow through the pipeline more easily), some of which entered the river.

Oil on the surface of the North Saskatchewan River on Friday 22 July 2016. CTV News Calgary.

The company initially attempted to control the spill by shutting down the pipeline and placing a boom across the river to trap the oil, about 40 km upstream of North Battleform. However high water levels enabled the oil to overtop the boom and spread further downstream. A second boom has now been emplaced lower on the river, and residents and businesses are being asked to restrict water use in North Battlefield. Concerns have also been raised that the spill may affect water supplies in Prince Albert, further down the North Saskatchewan.

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http://sciencythoughts.blogspot.co.uk/2016/05/canadian-city-evacuated-due-to-forest.htmlCanadian city evacuated due to forest fires. The city of Fort McMurray in northeastern Alberta, Canada has ordered the evacuation of its entire population after it became clear that it could not be protected from wild fires sweeping across the region's forests. An initial evauaction order for 12 of the cities districts was issued at 5.00 pm on Tuesday 3 May...
http://sciencythoughts.blogspot.co.uk/2015/09/canadian-homes-evacuated-following-fire.htmlCanadian homes evacuated following fire at Minnesota natural gas plant.                     Homes have been evacuated as a precaution in parts of Emerson, Manitoba, following a fire at a natural gas plant at St Vincent in Kittson County, Manitoba...
http://sciencythoughts.blogspot.co.uk/2015/02/apartment-block-evacuated-after-fire-at.htmlApartment block evacuated after fire at North Dakota oil treatment center.                           An apartment block to the south of Watford City in North Dakota was temporarily evacuated following a fire at a nearby oil treatment center which broke out at about 6.30 pm local time on Saturday 14 February 2015, according to McKenzie County...
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Friday, 22 July 2016

Sewage spill closes waterfront at Long Beech, California.

Parts of the harbour in Long Beech, Los Angeles, had to be closed off after a collapsed pipeline leaked about nine million liters of sewage into the Los Angeles River on Monday 18 July 2016. The sewage entered the river about 30 km upstream from the Harbour, but was rapidly swept down to the sea.

Asign warning against entering the water at Long Beech on Tuesday 19 July 2016. Steve McCrank/The Daily Breeze/AP.

As well as the obvious dangers to health presented by sewage, which is likely to contain a variety of Bacteria and other micro-organisms harmful to Human health, sewage provides a source of nutrients which can lead to eutrophication and the rapid growth of blooms of Algae, Bacteria or other micro-organisms, which absorb oxygen from the water leading Fish and other aquatic organisms to asphyxiate.

See also...

http://sciencythoughts.blogspot.co.uk/2016/02/cleanup-underway-after-sewage-spill-in.htmlCleanup underway after sewage spill in Bellingham, Washington.                                 A cleanup operation is underway after about 1 140 000 liters of sewage was spilt into Padden Creek in the south of Bellingham in Whatcom County...
http://sciencythoughts.blogspot.co.uk/2015/12/widespread-lead-poisonng-prompts-city.htmlWidespread lead poisonng prompts city of Flint, Michigan, to declare a state of emergnecy.                                                   The City of Flint, in Genesee County, Michigan, has declared a stare of emergency, following an outbreak of lead poisoning in the city. Mayor Karen...
http://sciencythoughts.blogspot.co.uk/2015/11/magnitude-35-qrthquake-beneath-northern.htmlMagnitude 3.5 £qrthquake beneath northern Los Angeles.                                               The United States Geological Survey recorded a Magnitude 3.5 Earthquake at a depth of about 3 km beneath the Pacoima district of Los...
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