Thursday 28 January 2016

Ammotragus lervia: The diet of the Barbary Sheep in the Bou Hedma Mountains of Tunisia.

The Barbary Sheep (or Aoudad), Ammotragus lervia, is a wild Caprid found in North Africa, from the Mediterranean as far south as the Niger and Lake Chad, and introdiced to other parts of the world such as North America and the Canary Islands. The species is now missing from much of its original range, having suffered from habittat loss Human encroachment, overhunting and competition with domestic animals, and is considdered Vulnerable under the terms of the International Union for the Conservation of Nature's Red List of Threatened Species. This has led to a number of recent studies of the species popuation and distribution, but other aspects of its biology have tended to be overlooked. In Tunisia the species is nearly extinct and considdered tobe Critically Endangered under the National Register of Wild Species.
  
In a paper published in the South African Journal of Science on 23 November 2015, Jamel Ben Mimoun and Saïd Nouira of the Laboratory of Animal Ecology at the Tunis El Manar University discuss the results of a study of the diet of the Barbary Sheep in the Bou Hedma National Park in central Tunisia.

 Barbary Sheep, Ammotragus lervia, at Oued Dekouk in Tunisia. Steve Morgan/Mammal Watching.

Ben Mimoum and Nouira examined Barbary Sheep droppings collected at monthly intervals between March 2009 and February 2010 in order to determine the proportions of different plants in the diet of the living animals. They found that two species of Grass, Stipa parviflora and Stipa tenacissima, formed the bulk of the Sheep's diet, together forming 63.2% of the plant matter consumed. However there was a strong seasonal variation in the amount of these Grasses consumed, so that they formed 69.1% of the diet in spring, 78.3% of the diet in summer, 56.6% of the diet in autumn and 34.7% of the diet in winter.

Thus Grasses form the bulk of the plant matter consumed in spring and summer (though the maximum number of different plant species were consumed in spring), In autmn browsing on trees and shrubs played a more important part in the diet, with Pistacia lentiscus comprising 7.4% of the plant matter consumed, Juniperus phoenicea 5.9% and Periploca laevigata 5.2%. Periploca laevigata remained an important part of the diet in winter, forming 5.5% of the diet. The herbaceous plant Helianthemum kahiricum was also important in autumn and winter, when it formed 13.6% and 13.0% of the diet, with two other herbaceous plants becoming important in winter; Globularia alypum, which formed 14.6% of the winter diet, and Helianthemum semiglabrum, which formed 12.1% of the winter diet.

 The current distribution of the Barbary Sheep, Ammotragus lervia, in North Africa. International Union for the Conservation of Nature's Red List of Threatened Species.

The Barbary Sheep is a highly flexible herbivore, known to be able to consume a wide range of plant species. In Texas, where it has been introduced, it has been shown to regularly consume 25 species of plants, in the Canaries 41, and in New Mexico 74 species. In Bou Hedma the species only consumed 19 identifiable species of plants, which is likely to be a result of a lack of suitable alternatives rather than a lack of willingness to consume other plants. Nevertheless the Tunisian Barbary Sheep shows a clear preference for Grasses when these are available, something which has previously been observed in Barbary Sheep in Texas and California, though other studies of the Sheep in Texas, New Mexico and Morocco have found browsing on trees and shrubs to play a more important role in the species diet. It was noted that the Tunisian Sheep showed a clear preference for open grassland during the breeding season, and that this was also the time of maximum Grass growth.

See also...

http://sciencythoughts.blogspot.co.uk/2016/01/mapping-distribution-of-southern-pudu.htmlMapping the distribution of the Southern Pudú in Chile.                                               The Southern Pudú, Pudu pudu,  is one pf the world's smallest Deer species, typically weighing 35 to 45 cm at the shoulder and weighing 6.4 to 13.4 kg. It is found in southern Chile and Argentina, and is listed as...
http://sciencythoughts.blogspot.co.uk/2013/08/how-fencing-tibetan-prairies-is.htmlHow fencing the Tibetan prairies is effecting the endangered Przewalski’s Gazelle. The Przewalski’s Gazelle (Procapra przewalskii) is a species of high altitude adapted Antelope, which formerly ranged across much of northwestern China and Inner Mongolia. It is now restricted to a small area around Qinghai Lake on the Tibetan Plateau, with a...
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Saturday 23 January 2016

Arulenus miae: A new species of Pygmy Devil from Mindanao Island (& Facebook).

Pygmy Devils, Discotettiginae, are small members of the Tetrigidae (Dwarf Grasshoppers) from South and East Asia. They are generally terrestrial, feeding on Algae and Bryophytes (Non-vascular Plants), though some species are semi-aquatic and feed on aquatic Algae and Plants.

In a paper published in the journal Zootaxa on 22 January 2016, Josep Skejo of the Special Interest Group Tetrigidae of the Biology Students Association at the Department of Biology at University of Zagreb and Joy Caballero of the Department of Biology at Central Mindanao University describe a new species of Pygmy Devil from Mindanao Island in the Philippines.

The new species was first recognized by Josep Skejo from a photograph posted on the Orthoptera Facebook group, with specimens later found for sale on the LesColeopteres webpage. The species was subsequently located in the wild by a team led by Alma Mohagan of the Central Mindanao University. It is placed in the genus Arulenus, and given the specific name miae, in honour of Miae Jurić, a student of Fashion and Textile Design at the Faculty of Textile Technology at the University of Zagreb, and friend of Josep Skejo. 

Original Facebook image of the first specimen of Arulenus maiae. Leif Gabrielsen in Skejo & Caballero (2016).

The species is large for a Pygmy Devil, with the largest specimens reaching about 13 mm in length. Its body has a generally smooth texture, covered in small granulations. They are predominantly black in colour, with a black or dark brown head, with yellow eyes and a number of yellow tubercles and dorsal spines with red tips.

 Skejo and Caballero further note that social media present a great deal of potential for natural historians in general and entomologists in particular, with images being shared on a variety of platforms, such as EBay and Flikr, and in particular Facebook, where there are a number of specialist groups for entomologists and orthopterists, such as Entomology, Insect Identification, InsectIndia, Orthoptera, The Orthopterists Society and Orthotera of Thailand.

See also...

http://sciencythoughts.blogspot.co.uk/2014/08/a-new-species-of-pygmy-grasshopper-from.htmlA new species of Pygmy Grasshopper from Miocene Dominican amber.                      Pygmy Grasshoppers (Tetrigidae) are small Orthopteran Insects related to True Grasshoppers, Crickets and Katydids, found across much of the globe but most numerous and diverse in the tropics...
http://sciencythoughts.blogspot.co.uk/2014/06/a-new-species-of-cockroach-wasp-from.htmlA new species of Cockroach Wasp from Thailand.                                               Cockroach Wasps (Ampulicidae) are a group of Digger Wasps (Aculeata) which specialize in the hunting of Cockroach prey. Some of these Wasps are...
http://sciencythoughts.blogspot.co.uk/2012/08/a-new-species-of-green-lacewing.htmlA new species of Green Lacewing discovered on Flikr®.                                                   Green Lacewings (Chrysopidae) are a globally distributed group of carnivorous flying Insects, ranging from 6 to 65 mm in length (though the larger... 
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Friday 22 January 2016

Transition disks around LkCa 15.

Planets are thought to form in protoplanetary disks, which is to say disks of gas and dust around young stars. However not all the material in a protoplanetary disk is likely to be used up in the formation of planets, leaving one or more debris disks, such as the Main Asteroid Belt and Kuiper Belt in our own Solar System. These debris disks typically contain rocky and icy bodies, but not free gas. However this is not an instantaneous event, and a period exists where a planetary system is forming accompanied by one or more disks of dust and gas; these evolving disks in forming planetary systems are called 'transition disks.

In a paper published on the arXiv database at Cornell University Library on 5 January 2015 and accepted for publication in the Publications of the Astronomical Society of Japan, a team of scientists led by Daehyun Oh of the Department of Astronomical Science of the Graduate University for Advanced Studies and the National Astronomical Observatory of Japan discuss the results of a study of the LkCa 15 stellar system and its transition disks made with the Subaru Telescope.

LkCa 15 is a young (2-5 million-year-old) K5-type orange dwarf star, roughly 547 light years from Earth in the constellation of Taurus. It has approximately the same mass as the Sun but only about 74% of its luminosity, new material is still accreting onto the star at a rate of about one Earth mass every 23 years.  The system has a well documented transition disk as well as two candidate planets, with a second inner disk having been discovered in 2015.

Oh et al. were able to clearly resolve two elliptical disks around LkCa 15, these are apparently in the same plane, tilted at a angle of 44˚ from our perspective. However the gap separating these disks, which forms an apparent third component to the system, appears to be tilted at a greater angle, 52˚. Since this gap is only an apparent member of the disk system, not a genuine object, this apparent difference in angle can only be a product of the structure of the two actual rings.

PI and overlapped polarization vector map images (2.0′′ × 2.0′′) before (a) and after (b) halo subtraction. The saturated region is occulted by a software mask (r∼0.1′′ ), the vectors are binned with spatial resolution, and the lengths are arbitrary for presentation purposes. (a): The effect of a polarized halo appears to have a tendency toward the minor axis of the disk. (b): The polarization tendency to the minor axis was removed, and the disk-origin polarization along the disk surface was revealed. Bottom: The radial Stokes Qr (c) and Ur (d) images. In the Qr image, both the outer and inner disks are significantly detected as expected from the PI image. On the other hand, the Ur image shows no disk-like component. Oh et al. (2015).

In order to resolve this Oh et al. examined the brightness asymmetries of the disks in order to glean further information about their inclination. This works because the side of the disk behind the star is reflecting light directly back towards us, whereas light reaching us from the near side has to be scattered through the disk. Using this method they found that the inner portions of the disks were misaligned by about 13˚, the best explanation for this being that the inner disk is significantly warped.

Elliptical fitting results of the inner disk (purple), the gap (yellow), and the outer disk (red). The image has been smoothed by a gaussian with r=2 pixels to reduce the effects of speckles on the inferred structure of the disk. The central region is also shown in the right top panel. White star indicates the location of LkCa 15. Green and orange stars indicate where the planet candidates LkCa 15 b and c were detected in 2014, respectively (Sallum et al. 2015). Empty green and orange circles indicate the locations of two infrared sources seen in 2009-2010 (Kraus & Ireland 2012), which are assumed as LkCa 15 b and c, respectively. Oh et al. (2015).

This study greatly adds to the evidence for the presence of one or more planets or protoplanets in the LkCa 15 system. The warping of the inner disk observed would require the presence of a planet with a planet having a mass at least equivalent to that of Jupiter, while the gap between the two disks is about 27 AU (27 times the distance at which the Earth orbits the Sun), which would require multiple such large planets to clear.

See also...

http://sciencythoughts.blogspot.co.uk/2015/12/detecting-debirs-disks-around-small.htmlDetecting debris disks around small nearby stars in old Hubble images.                        Debris disks are rings of dust, rock and icy material left surrounding stars after planet formation has occurred (unlike protoplanetary disks, which are present around very young stars only, and which are thought to be largely consumed by planetary formation). Our Solar System has two such debris disks, the Asteroid Belt and the Kuiper Belt, and in recent years...
http://sciencythoughts.blogspot.co.uk/2015/03/the-outer-disk-of-t-chamaeleontis.html

The outer disk of T Chamaeleontis.                 T Chamaeleontis is a T Tauri star (a very young star which has not yet began to generate heat by hydrogen fusion, but which produces considerable energy through gravitational heating) estimated to be about 7 million years old, roughly 350 light years from Earth in the constellation of Chamaeleontis. It is known to be surrounded by two transition disks (disks of dust and gas surrounding very young stars, thought to...

 

http://sciencythoughts.blogspot.co.uk/2014/07/the-keplerian-disk-of-class-i-protostar.htmlThe Keplerian Disk of Class I Protostar L1489 IRS.                                               Recent studies of the Keplerian Disks around other Protostars with the Submillimeter Array (SMA) have suggested that in the early Class 0 Protostar stage little rotation occurs within the Keplerian Disk and the rate of infalling (i.e. the rate at which material falls from the Disk onto the Protostar) is high. In late...


  

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Fossil Fleas from the Mesozoic - are they or aren't they?

Putative Mesozoic fossil Fleas were first recorded in Australia and Russia in the 1970s, with a number of recent publications describing Fleas from the Jurassic and Cretaceous of China. These Fleas have been speculated to have been ectoparasites (parasites that live on the exterior surfaces of their hosts) of a range of vertebrate animals, including feathered Dinosaurs, Birds, Pterosaurs and Mammals, however these associations are all based upon the presence of the Flea fossils in the same strata as their possible hosts; no Flea has been found preserved within the fur or feathers of a host animal.

In a paper published in the journal BMC Evolutionary Biology on 11 January 2016, Katharina Dittmar of the Department of Biological Sciences and Graduate Program of Evolution, Ecology, and Behavior at the University at Buffalo, Qiyun Zhu, also of the Department of Biological Sciences at the University at Buffalo, Michael Hastriter of the Monte L. Bean Museum at Brigham Young University and Michael Whiting of the Department of Biology and M. L. Bean Museum at Brigham Young University review these findings and find no evidence that the Insects preserved were or were not Fleas and/or ectoparasites of vertebrate animals.

Fleas can be identified morphologically by a number of features, these being lateral (sideways) flattening, the absence of wings combined with a highly modified wing joint, a saddle-shaped pygidium (structure formed of the rearmost segments), highly modified rear legs allowing the distinctive jumping movement associated with Fleas, mouthparts modified to form a piercing stylet and reduced eyes. While the numerous putative 'Flea' fossils are generally Flea-like in appearance, only two of these features, reduced eyes and modifieds mouthparts forming a piercing stylet, have been observed, both of which are known to have arisen separately in a wide range of Insect groups, preventing the confident assignment of these Insects to the order Siphonaptera (Fleas). Furthermore Dittmar et al. note that genetic studies of Fleas using molecular clock methodologies have predicted that the group arose some time during the Cretaceous, making putative Jurassic and even Early Cretaceous fossil Fleas somewhat unlikely.

 A possible fossil Flea from the Early Cretaceous Yixian Formation of Liaoning Province, China. Gao etal. (2014).

From an ecological perspective these Insects have been identified as animal ectoparasites based upon the presence of piercing stlylets and the presence of claws and bristles which would enable them to cling onto their hosts. However such stylets are present in Insects with a range of different lifestyles, including bloodsucking (Fleas, Mosquitoes), sucking the sap of plants (Aphids) and even predating other invertebrates (Assassin Bugs), and so cannot be taken in themselves as evidence of a bloodsucking lifestyle, while claws and bristles facilitate movement in a variety of complex three dimensional environments, not just feathers and fur, leading Dittmar et al. to conclude there is no evidence for or against an ectoparasitic lifestyle in these specimens.

See also...

http://sciencythoughts.blogspot.co.uk/2014/12/a-new-species-of-flea-from-early.htmlA new species of Flea from the Early Cretaceous of Liaoning Province, China.      The first Mesozoic fossil Fleas were discovered in Cretaceous deposits in Australia and Russia in the 1970s. However no further Mesozoic Fleas...

http://sciencythoughts.blogspot.co.uk/2013/04/a-new-species-of-flea-from-philippines.htmlA new species of Flea from the Philippines. Fleas of the Family Stivaliidae are found across Africa, Australasia and Southeast Asia. They are specialist parasites of Rodents and Shrews (and...
http://sciencythoughts.blogspot.co.uk/2012/03/giant-fleas-from-jurassic-of-china.htmlGiant Fleas from the Jurassic of China.      Fleas are highly specialized parasitic insects, preying on mammals and birds. They are related to Flies and Scorpionflies, though this relationship is not obvious as Fleas have become physically specialized, loosing their wings, altering their body shape and evolving specialized legs and mouthparts. A number of putative fossil fleas have been described from the Jurassic...
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Tuesday 19 January 2016

Sierra Leone reports a new case of Ebola.

Between December 2013 and December 2015 an outbreak of the Viral disease Ebola, which causes an acute hemorrhagic fever, killed a total of 11 315 people in West Africa, with the vast majority of fatalities in Liberia (4809 deaths), Sierra Leone (3955 deaths) and Guinea (2536 deaths). The outbreak was declared over on 14 January 2016, when Liberia was declared officially free of the Virus by the World Health Organization, the last country to be so cleared. However on 15 January Sierra Leone, a country thought to have been clear of the virus since 7 November 2015, reported the death of a young woman earlier this week was confirmed to have been caused by the disease.

Sierra Leone. Wikipedia.

The woman has not been identified, but is understood to have been a 22-year-old student from Lunsar in Port Loko District, who may have contracted the disease in Kambia District, where she stayed from Christmas until 6 January. The woman fell ill while visiting a family home in Tonkalili, and admitted to hospital after visiting a hospital outpatients department suffering from dizziness, and died on 12 January. 

Ebola was not identified while the woman was alive, as she showed no typical signs of the illness. However the disease was diagnosed from swabs which were taken after death as part of an ongoing screening program and sent for testing at Public Health England in the UK. This means that since the since the illness was not identifies until after the victim was buried, none of the precautions usually taken against the spread of the highly contagious disease were taken.

A hundred and nine people have been identified as having ha potentially hazardous contact with the woman, with 28 considered to be at high risk, Three of these people have yet to be traced.Officials from the World Health Organization have also suggested that the burial of the victim may not have been carried out in a safe fashion.

This resurgent outbreak has been linked to the discovery that the disease can linger in other bodily fluids long after it has been cleared from the blood of recovered victims, providing a potential reservoir of infection that cannot be detected by conventional blood tests.

See also...

http://sciencythoughts.blogspot.co.uk/2015/11/evidence-for-sexual-transmission-of.htmlEvidence for sexual transmission of the Ebola Virus.                                                                             In December 2013 cases of Ebola, a viral haemorrhagic fever with an extremely high mortality rate, began to emerge in Guinea, West Africa, marking the beginning of the most severe outbreak of the disease...
In December 2013 cases of the haemorrhagic Virus...
http://sciencythoughts.blogspot.co.uk/2014/07/at-least-467-dead-in-west-african-ebola.htmlAt least 467 dead in West African Ebola outbreak.                                                        At least 467 people have died in an outbreak of  Ebola Hemorrhagic Fever in West Africa that began in February this year. The disease initially appeared in the remote border area between Guinea, Sierra Leone...
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Monday 18 January 2016

Magnitude 5.1 Earthquake off the south coast of Cuba.

The United States Geological Survey recorded a Magnitude 5.1 Earthquake at a depth of 10 km off the south coast of Cuba, slightly before 3.30 am local time (slightly before 8.30 m GMT) on SundaY 17 January 2016. There are no reports of any damage or injuries associated with this event, however people have reported felling it in the Guantanamo Bay area.

 The approximate location of the 17 January 2016 south Cuba Earthquake. Google Maps.

Cuba lies on the southern portion of the North American Plate, to the north of the Septentrional Fault Zone, which forms the boundary with the Gonâve Microplate, a small tectonic plate underlying northern Jamaica and most of the island of Hispaniola. The Gonâve Microplate is moving east relative to the North American Plate, pushed by the Mid-Cayman Spreading centre to the west of Jamaica.

To the south the Gonâve Microplate is separated from the Caribbean Plate by the Enriquilo-Plantain Garden Fault Zone, which runs across Southern Haiti and the Dominican Republic. To the west the fault runs through central Jamaica. The Caribbean Plate is rotating clockwise, effectively moving east relative to the Gonâve Microplate.

 Plate movements and fault zones around the Gonâve Microplate. Mike Norton/Wikimedia Commons.

None of these movements are smooth, with rock formations at the boundaries of the plates constantly sticking together then breaking apart as the pressure from the plate movement builds up, triggering Earthquakes in the process.

Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organization Earthquake Report is interested in hearing from people who may have felt this event; if you felt this quake then you can report it to Earthquake Report here.

See also...

http://sciencythoughts.blogspot.co.uk/2015/03/magnitude-47-earthquake-off-south-coast.htmlMagnitude 4.7 Earthquake off the south coast of the Dominican Republic.                   The United States Geological Survey recorded a Magnitude 4.7 Earthquake at a depth of 20.8 km off the south coast of the...

http://sciencythoughts.blogspot.co.uk/2015/01/magnitude-48-eathquake-in-southwest.htmlMagnitude 4.8 Eathquake in the southwest Dominican Republic.                            The United States Geological Survey recorded a Magnitude 4.8 Earthquake at a depth of 10 km in San Cristóbal Province in the...
http://sciencythoughts.blogspot.co.uk/2014/06/magnitude-45-earthquake-on-north-coast.htmlMagnitude 4.5 Earthquake on the north coast of the Dominican Republic.                         The United States Geological Survey recorded a Magnitude 4.5 Earthquake at a depth of 10 km on the north coast of the Dominican Republic, slightly...
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Neenchelys gracilis: A new species of Worm Eel from Taiwan.

Worm Eels, Ophichthidae, are burrowing Eels found in tropical and temperate waters from the coastal shallows to depths of about 750 m, with some species found in freshwater ecosystems. They range from about 10 cm to about 3 m in length, and are highly adapted to their burrowing lifestyle, with many species having lost their fins completely, with larger species occasionally mistaken for Sea Snakes.

In a paper published in the journal Zootaxa on 24 December 2015 Hsuan-Ching Ho of the National Museum of Marine Biology & Aquarium and Institute of Marine Biology at the National Dong Hwa University and Kar-Hoe Loh of the Institute of Ocean and Earth Sciences at the University of Malaya describe a new species of Worm Eel from off the coast of Dong-gang on the southeast coast of Taiwan.

The new species is placed in the genus Neenchelys and given the specific name gracilis, meaning slender. The species is described from a single specimen caught in a otter trawl at a depth of about 400 m. The specimen is 429 mm in length, with a fringe of cirri around its nostrils; it has small gill openings and has almost completely lost its pectoral fins (paired fins behind the gills). It is a brownish grey colour.

 Neenchelys gracilis. Lateral view of whole fish. Bars indicate the locality of the dorsal-fin origin (left) and the anus (right). Ho & Loh (2015).

See also...

http://sciencythoughts.blogspot.co.uk/2014/06/japanese-eel-classified-as-endangered.htmlJapanese Eel classified as Endangered.        The International Union for the Conservation of Nature published its annual update of its Red List of Threatened Species on Thursday 12 June 2014, marking the 50th year of the list's existence, and revising the status of a number of Plant and Animal species from around...
http://sciencythoughts.blogspot.co.uk/2013/05/the-effect-of-parasitic-nematodes-on.htmlThe effect of parasitic Nematodes on European Eels.                                       European Eels, Anguilla anguilla, have a complex life-cycle; they hatch from eggs in the Sargasso Sea...
http://sciencythoughts.blogspot.co.uk/2012/01/living-fossil-eel-discovered-in-palau.htmlA living fossil eel discovered in Palau.            Eels first appear in the fossil record about 100 million years ago, in the Mid Cretaceous. These Cretaceous forms are primitive compared to modern forms, with incomplete fusion of the dorsal, caudal and anal fins, scales on their bodies and many of the bones lost or fused still present. However they are still clearly eels, with elongate bodies and the loss and fusion of...
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Asteroid 2016 AH164 passes the Earth.

Asteroid 2016 AH164 passed by the Earth at a distance of 26 660 km (0.08 times the average distance between the Earth and the Moon, or 0.02% of the average distance between the Earth and the Sun; 6660 km above the orbit at which the satellites supporting GPS systems operate), slightly before 3.25 am GMT on Tuesday 12 January 2016. There was no danger of the asteroid hitting us, though had it done so it would have presented only a minor threat. 2016 AH164 has an estimated equivalent diameter of 2-6 m (i.e. it is estimated that a spherical object with the same volume would be 2-6  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 more than 37 km above the ground, with only fragmentary material reaching the Earth's surface.

 The calculated orbit of 2016 AH164JPL Small Body Database.

2016 AH164 was discovered on 13 January 2016 (the day after its closest approach to the Earth) by the University of Arizona's Catalina Sky Survey, which is located in the Catalina Mountains north of Tucson. The designation 2016 AH164 implies that it was the 4108th asteroid (asteroid H164) discovered in the first half of January 2016 (period 2016 A).

2016 AH164 has a 674 day orbital period and an eccentric orbit tilted at an angle of 0.70° to the plane of the Solar System that takes it from 0.94 AU from the Sun (i.e. 94% of the average distance at which the Earth orbits the Sun) to 2.07 AU from the Sun (i.e. 207% of the average distance at which the Earth orbits the Sun, considerably more than the distance at which Mars orbits). 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). This means that close encounters between the asteroid and Earth are fairly common, with the last thought to have happened in October 2004 this year and the next predicted in August 2020.
 
See also...
 
http://sciencythoughts.blogspot.co.uk/2016/01/asteroid-2016-ao8-passes-earth.htmlAsteroid 2016 AO8 passes the Earth.     Asteroid 2016 AO8 passed by the Earth at a distance of 18 950 000 km (49.4 times the average distance between the Earth and the Moon, or 12.7% of the average distance between the Earth and the Sun), slightly before 0.55 am GMT on Saturday 2...
http://sciencythoughts.blogspot.co.uk/2016/01/asteroid-2015-xc352-passes-earth.htmlAsteroid 2015 XC352 passes the Earth.  Asteroid 2015 XC352 passed by the Earth at a distance of 1 991 000 km (5.18 times the average distance between the Earth and the Moon, or 1.33% of the average distance between the Earth and the Sun), slightly after 7.00 pm GMT on Wednesday...
http://sciencythoughts.blogspot.co.uk/2016/01/asteroid-2015-yv9-passes-earth.htmlAsteroid 2015 YV9 passes the Earth.      Asteroid 2015 YV9 passed by the Earth at a distance of 3 602 000 km (9.37 times the average distance between the Earth and the Moon, or 2.4`% of the average distance between the Earth and the Sun), slightly after 3.00 pm GMT on Saturday 26 December 2015...
 
 
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Sunday 17 January 2016

Notomela joliveti: A new species of Flea Beetle from Principe Island.

Flea Beetles, Alticini, are highly specialized Leaf Beetles, Chrysomelidae, which get their common name from their highly modified rear legs, which enable them to make sudden long jumps when threatened. They are small for Leaf Beetles, though not exceptionally so, and are herbivorous, with each species favoring a particular host plant, and some being serious agricultural pests.

In a paper published in the journal ZooKeys on 17 December 2015, Maurizio Biondi and Paola D’Alessandro of the Department of Health, Life and Environmental Sciences at the University of L’Aquila describe a new species of Flea Beetle from Principe Island off the west coast of Africa.

The new species is placed in the genus Notomela, which is widespread in Sub-Saharan Africa, and given the specific name joliveti, in honour of the entomologist Pierre Jolivet a preeminent worker in the field of Leaf Beetles. The species is described from three male specimens collected on the island in 1901 and housed at the Museo Civico di Storia Naturale in Genova. The new species is smaller than other members of the genus at 3,9-4.2 mm in length, and is a uniform greenish black in colour, unlike other members of the genus which have light brown heads and thoraxes. The host plant for this species is unknown.

Notomela joliveti, male specimen in dorsal view. Biondi & D'Alessandro (2015).

See also...

http://sciencythoughts.blogspot.co.uk/2015/12/pella-tianmuensis-new-species-of.htmlPella tianmuensis: A new species of Myrmecophilic Aleocharine Rove Beetle from Zhejiang Province, China.                     Aleocharine Rove Beetles are small Rove...
http://sciencythoughts.blogspot.co.uk/2015/12/cretonthophilus-tuberculatus-clown.htmlCretonthophilus tuberculatus: A Clown Beetle from Cretaceous Burmese Amber.           Clown Beetles, Histeridae, are a diverse group of carnivorous Beetles found across the globe. They are easy to distinguish, the elytra (wing cases) that do not cover the ends of their abdomens and club-like tips to their antennae. They occupy a wide range of...
http://sciencythoughts.blogspot.co.uk/2015/10/awas-gigas-new-species-of-rove-beetle.htmlAwas gigas: A new species of Rove Beetle from Guangxi Province, China.                  Rove Beetles, Staphylinidae, of the genus Awas are tiny Beetles with elongate heads and constricted waists found living in Ant's nests on the Malay Peninsula, in Taiwan and in continental China. The group is poorly understood, with three of the five described species being known only from a sngle specimen, and...
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Saturday 16 January 2016

Animal remains from Middle Neolithic deposits at the Pena d’Água Rock-shelter of Portugal.

Middle Neolithic remains are known from a number of archaeological sites across Portugal, and have been studied since the nineteenth century. However historically almost all studies of this material have concentrated on funerary behavior rather than the lifestyles of the living people. The Pena d’Água Rock-shelter is located on the eastern rim of the Estremadura Limestone Massif to the northeast of Lisbon. The site was excavated in 1992-2000, yielding remains dating from the end of the Pleistocene to the Roman era. A variety of animal bones and teeth were recovered from a layer identified as being of Middle Neolithic origin, with Rabbit, Sheep and/or Goat (the two are hard to tell apart from skeletal remains) and Fox remains being identified at the time, though these have not subsequently been the subject of any published studies.

In a paper published in the journal Estudos do Quaternário in December 2015, Fransisco Rosa Corriera and the Sofia Luís of the Universidade do Algarve, Pedro Valente Fernandes of the Universidade do Algarve and the Núcleo de Alunos de Arqueologia e Paleoecologia, and Maria João Valente and António Faustino Carvalho, also of the Universidade do Algarve re-examine the Middle Neolithic animal remains from the Pena d’Água Rock-shelter in order to determine the animals present and the implications of this for the lifestyles of the people.

(A) Location of Estremadura and the Tagus Valley in western Iberia. (B) Location of the mentioned archaeological sites (1 - Pena d’Água Rock-shelter; 2 - Costa do Pereiro; 3 - Cadaval Cave). (C) A view of the Pena d’Água Rock-shelter (arrow) in Google Earth showing the Arrife clearly separating the two contrast-ing landscapes, the limestone mountain (right) and the Tagus plain (left). (D) Detail image of the Arrife showing the Pena d’Água Rock-shelter (arrow indicates the sector of the deposit where excavations took place). Corriera et al. (2015).

All of the remains assessed to be Middle Neolithic come from a single layer, Db, which also contains pottery fragments, stone tools and charcoal. The pottery fragments showed simpler decoration and were less varied than earlier layers assessed to be Early Neolithic in age, though the stone tools were more sophisticated and include large, complex flint blades. The charcoal was found to be derived from Olive wood, and yielded a radiocarbon age of 5180 years, though with a wide margin of error, leading Corriera et al, to conclude that the layer was laid down between 4522 and 3515 BC.
 

Stratigraphy of the Pena d’Água Rock-shelter (“West Cut”), with indication of layer Db (greyish layer) within the sequence. Z0=630 cm is the local datum used during excavations. Corriera et al. (2015).

The most abundant bones in the layer are those of Rabbits, Oryctolagus cuniculus. Identifying Rabbits in archaeological sites can be problematic. as they are burrowing animals which can place tunnel into site long after they were abandoned by their Human residents. However all of the remains at Pena d’Água are aof adult specimens, and in addition all are disarticulated and fragmentary, and many are charred, suggesting strongly that the remains are the result of Human activity.

The site also yielded several teeth from Fox, Vulpes vulpes, and an uncertain Deer (possibly a Red Deer, Cervus elaphus). Both of these are though to be the result of hunting by Humans, possibly with only partial remains being transported to the site. Red Deer are prized for their meat today, and are likely to have been hunted for food in the Neolithic. Foxes on the other hand are not typically eaten, today, and probably weren't considered particularly palatable in the Neolithic. On the other hand their fur has been prized through much of recorded history, and this may have been the case at Pena d’Água.

Sheep and/or Goat remains are also abundant at the site. These are interpreted as being more probably the remains of domestic animals than wild ones. Domestication is known to have been in practice in the area at the time, with other sites having yielded the remains of Cattle and Pigs. However the methods used to keep these animals is quite different. Cattle and Pigs can be kept in corals and fed with a reasonable level of success, while Sheep and Goats need to be able to forage for themselves, requiring herders to move with the flock, so this discovery adds to the known range of survival skills being employed in Middle Neolithic Portugal.

See also...

http://sciencythoughts.blogspot.co.uk/2015/08/evidence-of-cereal-cultivation-by-sea.htmlEvidence of Cereal cultivation by the Sea of Galilee during the last Glacial Maximum, 23 000 years ago.                                                           The domestication of agricultural plants is thought to have begun in the Middle East around the onset of the Holocene, about 11 700 years ago, with agriculture rapidly spreading across Europe, Asia and northern...
http://sciencythoughts.blogspot.co.uk/2015/06/interpreting-life-history-of-egtved-girl.htmlInterpreting the life history of the Egtved Girl.                                                                                   The ‘Egtved Girl’ was excavated near Egtved...
http://sciencythoughts.blogspot.co.uk/2014/08/the-first-dairy-farmers-in-finland.htmlThe first dairy farmers in Finland.              Dairy farming (keeping Mammals in order to consume their milk or products derived from it) spread through Europe as part of the ‘Neolithic Package’ of technologies, which originated in the Middle East...
 
 
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