Thursday, 24 May 2018

Determining the diet of Miocene Gomphotheriid Proboscidean using phytoliphs preserved in dental calculus.

The first Proboscideans (Elephants), appeared in the Palaeocene, and like other herbivorous Mammals of this time are presumed to have been browsers (leaf and fruit eaters). Modern Elephants, in contrast, are primarily grazers (grass eaters). Grasses first appeared in the Cretaceous, but extensive grasslands did not become a distinct ecosystem until the Miocene around 23 million years ago. Early Proboscidians had low-crowned teeth, with few lophids (ridges), consistent with a browsing diet, while modern Elephants have high-crowned teeth with numerous lophids, which offers some protection agianst the abbrasive nature of Grasses. The switch to Grasses as a food possibly occured in the Gomphotheres, which appeared in the Middle Miocene and are thought to have been ancestral to True Elephants. The earliest members of the group were trilophadont (had three ridges on their teeth), while later forms, particularly those thought to be ancestral to True Elephants, were tetralophadont (had four ridges), suggestive of a switch towards a more Grass-based diet.

In a paper published in the journal Scientific Reports on 16 May 2018, Yan Wu of the Key Laboratory of Vertebrate Evolution and Human Origins at the Institute of Vertebrate Paleontology and Paleoanthropology of the Chinese Academy of Sciences, and the Center for Excellence in Life and Paleoenvironment, Tao Deng, also of the Key Laboratory of Vertebrate Evolution and Human Origins, and the Center for Excellence in Life and Paleoenvironmentm, and of the Center for Excellence in Tibetan Plateau Earth Sciences, Yaowu Hu and Jiao Ma, also of the Key Laboratory of Vertebrate Evolution and Human Origins, and of the Department of Archaeology and Anthropology at the University of Chinese Academy of Sciences, Xinying Zhou, again of the Key Laboratory of Vertebrate Evolution and Human Origins, and the Center for Excellence in Life and Paleoenvironment, Limi Mao of the Key Laboratory of Economic Stratigraphy and Palaeogeography, at the Nanjing Institute of Geology and Palaeontology, Hanwen Zhang of the School of Earth Sciences at the University of Bristol, and of the Earth Sciences Department at the Natural History Museum, Jie Ye, again of the Key Laboratory of Vertebrate Evolution and Human Origins, and Shi-Qi Wang, once again of the Key Laboratory of Vertebrate Evolution and Human Origins, and the Center for Excellence in Life and Paleoenvironmentm, and of the Center for Excellence in Tibetan Plateau Earth Sciences, examine the diets of two species of Middle Miocene trilophadont Gomphotheriid Proboscideans, by examining phytoliths (silica fragments produced by plants) preserved in dental calculus of six specimens from the Miocene Halamagai Formation in the northern Junggar Basin of Xinjiang Province, China.

The Middle Miocene deposits of the Junggar Basin produce a diverse range of Gomphotheriid specimens, accompanied by floral remains indicative of a largely forested environment. Late Miocene strata from the same area, in contrast, have a much less diverse Gomphotheriid fauna, dominated by a few tetralophadont forms, and a more arid, Grass-dominated environment, suggesting that this area may have played an important role in the switch between browsing and grazing behaviour in early Proboscideans.

Wu et al. examined calculus from four specimens of Gomphotherium connexum and two specimens of Gomphotherium steinheimense. Gomphotherium steinheimense is thought to have been closely related to the early tetralophadont Gomphotheriid Tetralophodon longirostris, while Gomphotherium connexum is a more distant relative.

Geography, geology, and phylogeny in relation to the study material. (A) The location of the study area (black star). The map was generated by GTOPO309 using Globalmapper (v10). (B) Stratigraphic column and polarity with palaeomagnetic age, also denoting the horizon of study material in the strata (in light yellow). (C) The 50% majority consensus tree from 29 maximum parsimonious trees showing the phylogenetic position of the Gomphotherium species and Tetralophodon longirostris, the number at each node representing the support value calculated by majority rules (percentages of supported MPTs in the total MPTs, which are always larger than 50%) and the orange frame indicating the sister-taxon relationship of Gomphotherium steinheimense and Tetralophodon longirostris. (D) Gomphotherium steinheimense, right m3. (E) Gomphotherium connexum, left M3. Wu et al. (2018).

Of the phytoliths obtained from the calculus of Gomphotherium connexum, between 40% and 50% were identified as having originated from Grasses, whereas between 28% and 34% could be identified as having come from broadleaved plants. This would at first seem to imply a diet with a high proportion of Grasses, but Grasses produce a far greater amount of phytoliths than broadleaved plants (hence their more abrasive nature), so this probably indicates a diet with a high proportion of broadleaved plants. In contrast about 85% of the phytolihs from the calculus of Gomphotherium steinheimense could be identified as having come from grasses, indicative of a much more Grass-based diet.

See also...


http://sciencythoughts.blogspot.co.uk/2017/11/image-of-elephant-human-conflict-wins.htmlhttp://sciencythoughts.blogspot.co.uk/2017/10/elephants-kill-four-rohingya-refugees.html
http://sciencythoughts.blogspot.co.uk/2017/02/elephas-cf-e-planifrons-new-elephant.htmlhttp://sciencythoughts.blogspot.co.uk/2017/02/loxodonta-cyclotis-african-forest.html
http://sciencythoughts.blogspot.co.uk/2016/03/partial-gomphothere-tooth-from-miocene.htmlhttp://sciencythoughts.blogspot.co.uk/2016/03/dating-pleistocene-stegodon-from-west.html
Follow Scieny Thoughts on Facebook.

Monday, 21 May 2018

Canadian couple survive being swept of mountain road by landslide.

A Canadian couple have survived after being swept of a mountain road by a landslide on Thursday 17 May 2018. Sheri Niemegeers from Weyburn in Saskatchewan and Gabe Rosescu from Regina, also in Saskatchewan, were travelling through the Kootenay Pass to visit friends for the Victoria Day weekend, when they were hit by a mudflow containing numerous trees, which swept their car off the road and down the mountainside. Both suffered multiple broken bones and are recovering in a nearby hospital.

The scene of a landslide that swept a couple off a mountain road in the Kootenay Pass, British Colombia, on 17 May 2018. BC Transportation.

The incident happened after several hours of heavy rain in the area. Landslides are a common problem after severe weather events, as excess pore water pressure can overcome cohesion in soil and sediments, allowing them to flow like liquids. Approximately 90% of all landslides are caused by heavy rainfall. British Colombia has suffered widespread flooding in the last week as high rainfall has combined with melting winter snows, resulting in about 4500 people across the province being forced to evacuate their homes.

See also...

http://sciencythoughts.blogspot.co.uk/2018/03/avalanche-kills-skier-in-british.htmlhttp://sciencythoughts.blogspot.co.uk/2018/02/british-colombia-avalache-victim-dies.html
http://sciencythoughts.blogspot.co.uk/2018/01/homes-evacuated-after-landslide-in.htmlhttp://sciencythoughts.blogspot.co.uk/2017/05/magnitude-62-earthquake-in-northwest.html
http://sciencythoughts.blogspot.co.uk/2015/10/magnitude-44-earthquake-off-coast-of.htmlhttp://sciencythoughts.blogspot.co.uk/2014/08/breach-of-mine-tailings-pond-leads-to.html
Follow Sciency Thoughts on Facebook.

Hawai'ian man injured by lava bomb from Mount Kilauea.

A Hawai'ian man has suffered a broken leg after being struck by a lava bomb (chunk of lava thrown from a volcano, in either liquid or solid form), described as being as heavy as a refrigerator, from Mount Kilauea on Hawai'i (or 'Big') Island on Sunday 20 May 2018. The man is described as having been on his balcony at the time of the incident. The volcano began erupting from a new fissure on its eastern flank on 3 May 2018, since when a series of fissures have opened up, producing several major lava flows, which have destroyed many homes and other properties, and at least one of which has reached the sea, producing a laze (toxic haze resulting from hot lava hitting water, producing chemical-laden steam. At the same time the volcano has produced a number of gas and ash columns, some of which have reached over three kilometres in height, which are described as being particularly rich in hydrochloric acid, sulphur dioxide and volcanic glass.

Lava flow on Mount Kilauea. USGS/AP.

The islands of Hawai'i have formed as a result of hotspot volcanism, with a mantle plume hotspot currently located under Big Island, Hawai'i, and each of the other islands being the result of previous activity from the same hotspot, with the oldest Islands in the northwest and newest in the southeast. A volcanic hotspot is an area where magma from deep inside the Earth is welling up through the overlying plate (in this case the Pacific) to create volcanism at the surface. Volcanoes move as they erupt, swelling as magma enters their chambers from bellow, then shrinking as that magma is vented as lava.

 The position of the Hawai'i Hotspot relative to the islands of Hawai'i. Joel Robinson/USGS/Wikimedia Commons.

See also...

http://sciencythoughts.blogspot.co.uk/2018/05/eruption-on-mount-kilauea-hawaii-leads.htmlhttp://sciencythoughts.blogspot.co.uk/2016/08/sewage-spill-closes-beaches-at-honolulu.html
http://sciencythoughts.blogspot.co.uk/2015/05/crater-collapse-triggers-explosion-on.htmlhttp://sciencythoughts.blogspot.co.uk/2014/09/homes-threatened-by-lava-flow-on-big.html
http://sciencythoughts.blogspot.co.uk/2014/08/magnitude-45-earthquake-on-big-island.htmlhttp://sciencythoughts.blogspot.co.uk/2014/06/magnitude-41-earthquake-on-western.html
Follow Sciency Thoughts on Facebook.

Sunday, 20 May 2018

Magnitude 5.1 Earthquake in Petorca Province, Chile.

The United States Geological Survey recorded a Magnitude 5.1 Earthquake at a depth of 32.7 km, 39 km to the northeast of the city of La Ligua in the Chilean province of Petorca slightly before 2.45 am local time (slightly before 6.45 am GMT) on Saturday 19 May 2018. There are no reports of any damage or injuries associated with this event, but people have reported feeling the event across much of central Chile, and parts of western Argentina.

The approximate location of the 19 May 2018 Petorca Earthquake. USGS.

Chile is located on the west coast of South America, which is also the convergent margin between the Nazca and South American Plates. The Nazca Plate is being subducted beneath the South American Plate and is sinking beneath the South American Plate. This is not a smooth process, the rocks of the two plates continuously stick together then, as the pressure builds up, break apart again, causing Earthquakes. As the Nazca Plate sinks deeper it is partially melted by the heat of the Earth's interior. Some of the melted material then rises up through the overlying South American Plate as magma, fuelling the volcanoes of the Chilean Andes.
 
 The subduction of the Nazca Plate beneath the South American Plate, and how it causes Earthquakes and volcanoes. Pacific Earthquake Engineering Research Center.
 
Witness accounts of Earthquakes can help geologists to understand these events, and the structures that cause them. The international non-profit organisation 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/2018/01/eruptive-activity-on-volcan-arrau-peak.htmlhttp://sciencythoughts.blogspot.co.uk/2017/12/landslide-kills-at-least-five-in.html
http://sciencythoughts.blogspot.co.uk/2017/11/magnitude-49-earthquake-in-petorca.htmlhttp://sciencythoughts.blogspot.co.uk/2017/10/magnitude-54-earthquake-in-el-loa.html
http://sciencythoughts.blogspot.co.uk/2017/09/magnitude-58-earthquake-off-coast-of.htmlhttp://sciencythoughts.blogspot.co.uk/2017/07/magnitude-51-earthquake-in-antofagasta.html
Follow Sciency Thoughts on Facebook.

Meganodontia haunuiensis, Elliptiolucina neozelandica, and Lucinoma saetheri: Three new species of Lucinid Bivalves from Miocene hydrocarbon seeps on eastern North Island, New Zealand.

Ludinid Bivalces, Lucinidae, are large marine Bivalves which lack syphons, but which have an elongate foot with a long chanel that serves the same purpose. All modern Lucinids host colonies of symbiotic sulfur-oxidizing Bacteria in their gills, which enable them to colonise and thrive in sulphur-rich subtidal sediments. The first Lucinids appeared in the Silurian, though they remained a minor constituent of Bivalve faunas until the Late Cretaceous, when they underwent a major radiation at roughly the same time as Mangroves and Seagrass meadows appeared, which may have been when they acquired their symbiont Bacteria. Lucinids also form a significant part of the communities that live around hydrocarbon seeps (areas where hydrocarbons escape into the sea from exposed deposits).

In a paper published in the journal Acta Palaeontologica Polonica on 28 March 2018,  Kazutaka Amano of the Department of Geoscience at Joetsu University of Education, Crispin Little of the School of Earth and Environment at the University of Leeds, and Kathleen Campbell of the School of Environment at the University of Auckland, describe three new species of Lucinid Bivalves from Early and Middle Miocene hydrocarbon seeps from the area around Hawke Bay on eastern North Island, New Zealand.

The first new species is placed in the genus Meganodontia, which currently contains two described species, a living species found off the coast of Taiwan, and a fossil species from Miocene seep-carbonates from Italy, as well as an undescribed species from the Miocene of Cuba, and is given the specific name haunuiensis, meaning 'from Haunui', in reference to the location where it was found. This species is smaller than other members of the genus, with described specimens ranging from 40.2 to 84.6 mm in length, and are subcircular and highly inflated in shape, and a broad, toothed hinge. The species was found in the Early Miocene Ihungia Limestone to the south of Hawke Bay,

Lucinid Bivalve Meganodontia haunuiensis from the lower Miocene Ihungia Limestone at Haunui and Ugly Hill, North Island, New Zealand. (A) Specimen UOA L4777, edentulous hinge plate of left valve (A₁,), left valve (A₂). (B) Specimen UOA L4581, dorsal view (B₁) and frontal view (B₂) of right valve. (C) Specimen UOA L4791, edentulous hinge plate of right valve. (D) Specimen UOA L4790, right valve of small specimen. (E) Specimen UOA L4782, dorsal view of slightly compressed specimen (E₁), left valve (E₂). (F) Specimen UOA L4792, dorsal view showing symmetric lunule in both valves (F₁), right valve showing internal mould (F₂), enlargement of the anterior adductor muscle scar of F₂ (F₃). (G) Specimen UOA L 4789, right valve, showing internal mould of small specimen. Scale bars 10 mm. Amano et al. (2018).

The second new species is placed in the genus Elliptiolucina, which currently contains five living species from the Indo-Pacific region, and given the specific name neozelandica, meaning New Zealand. This is a small species, with described specimens ranging from 17.1 to 34.9 mm in length, with a thin, flattened shell. It was found in the Middle Miocene Bexhaven Limestone at the Moonlight North seep sight, to the north of Hawke Bay.

Lucinid Bivalve Elliptiolucina neozelandica from the Middle Miocene Bexhaven Limestone at Moonlight North, North Island, New Zealand. (A) Specimen UOA L4771, dorsal view (A₁), right (A₂) and left (A₃) valves. (B) Specimen UOA L4783, dorsal view (B₁), right valve (B₂), internal mould of left valve (B₂), enlargement of anterior adductor muscle scar in B₂ (B₄). (C). Specimen UOA L4775, edentulous hinge plate of right valve (C₁), left valve (C₂). (D) Specimen UOA L4774, dorsal view (D₁), right (D₂) and left (D₃) valves. Scale bars 10 mm. Amano et al. (2018).

The third new species described is placed in the genus Lucinoma, whuch has 38 described living species as well as two previously described Miocene ones, from Italy and New Zealand, and is given the specific name saetheri, in honour of Kristian Saether of the University of Auckland, for his work on the hydrocarbon seep fauna of New Zealand. This is a large species, with measured specimens ranging from 39.6 to 67.4 mm in length, with a thick, subcircular shell, with is moderately inflated with week ribs and a straight antero-dorsal margin. The species was found in the Early Miocene Ihungia Limestone to the south of Hawke Bay, and the Middle Miocene Bexhaven Limestone at the Moonlight North seep sight, to the north.

 Lucinid Bivalve Lucinoma saetheri from the lower Miocene Ihungia Limestone at Ugly Hill and the middle Miocene Bexhaven Limestone at Moonlight North, North Island, New Zealand. (A) Specimen UOA L4773, internal mould of right valve. (B) Specimen UOA L 4772, hinge plate of right valve. (C) Specimen UOA L4785, left (C₁) and right (C₂) valves. (D) Specimen UOA L4780, dorsal view (D₁), right (D₂) and left (D₃) valves. (E) Specimen UOA L4786, right valve. (F) Specimen UOA L 4779, left valve showing lamellated commarginal riblets (F₁), dorsal view (F₂). Scale bars 10 mm. Amano et al. (2018).

See also...

http://sciencythoughts.blogspot.co.uk/2017/08/a-hydrocarbon-seep-from-late-triassic.htmlhttp://sciencythoughts.blogspot.co.uk/2017/05/kuphus-polythalamia-can-giant-free.html
http://sciencythoughts.blogspot.co.uk/2016/09/borniopsis-mortoni-new-species-of.htmlhttp://sciencythoughts.blogspot.co.uk/2015/12/evidence-for-middle-permian-extinction.html
http://sciencythoughts.blogspot.co.uk/2015/03/the-reaction-of-marine-invertebrates-to.htmlhttp://sciencythoughts.blogspot.co.uk/2015/01/a-new-probably-fossil-species-of.html
Follow Sciency Thoughts on Facebook.

Asteroid 2018 HL2 passes the Earth.

Asteroid 2018 HL2 passed by the Earth at a distance of about 18 775 000 km (48.9 times the average distance between the Earth and the Moon, or 12.5% of the distance between the Earth and the Sun), slightly before 5.55 pm GMT on Sunday 13 May 2018. There was no danger of the asteroid hitting us, though were it to do so it would have presented a significant threat. 2018 HL2 has an estimated equivalent diameter of 110-340 m (i.e. it is estimated that a spherical object with the same volume would be 110-340 m in diameter), and an object of this size would be predicted to be capable of passing through the Earth's atmosphere relatively intact, impacting the ground directly with an explosion that would be 600 to 75 000 000 times as powerful as the Hiroshima bomb. Such an impact would result in an impact crater 1.5-5 km in diameter and devastation on a global scale, as well as climatic effects that would last years or even decades.
 
 The calculated orbit of 2018 HL2. Minor Planet Center.
 
2018 HL2 was discovered on 26 April 2018 (17 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 2018 HL2 implies that the asteroid was the 61st object (object L2) discovered in the second half of April 2018 (period 2018 H).   
 
2018 HL2 has a 788 day orbital period and an eccentric orbit tilted at an angle of 33.5° to the plane of the Solar System, which takes it from 0.89 AU from the Sun (i.e. 89% of he average distance at which the Earth orbits the Sun) to 2.45 AU from the Sun (i.e. 245% of the average distance at which the Earth orbits the Sun, and much further from the Sun than 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). As an asteroid probably larger than 150 m in diameter that occasionally comes within 0.05 AU of the Earth, 2018 HL2 is also classified as a Potentially Hazardous Asteroid. 2018 HL2 has occasional close encounters with the planet Earths, with the next predicted for May 2154.
 
See also...
 
http://sciencythoughts.blogspot.co.uk/2018/05/asteroid-2018-jg3-passes-earth.htmlhttp://sciencythoughts.blogspot.co.uk/2018/05/asteroid-2017-wy14-passes-earth.html
http://sciencythoughts.blogspot.co.uk/2018/05/comet-c2016-r2-panstarrs-reaches.htmlhttp://sciencythoughts.blogspot.co.uk/2018/04/asteroid-2018-hv-passes-earth.html
http://sciencythoughts.blogspot.co.uk/2018/04/asterpid-2018-hc1-passes-earth.htmlhttp://sciencythoughts.blogspot.co.uk/2018/04/asteroid-2018-hm-passes-earth.html
Follow Sciency Thoughts on Facebook.

Cougar kills cyclist in Washington State, USA.

A cyclist has died after being attacked by a Cougar (or Mountain Lion, or Puma), Puma concolor, to the northeast of Snoqualmie, in King County, Washington, on Saturday 19 May 2018. The dead man was one of two mountain bikers who apparently disturbed the animal while out cycling, and who were initially able to drive off the Cougar by making themselves look larger and waving their arms about. However the Cat returned and attacked one of the men, causing his companion to dismount and try to tackle it. When the Cougar turned on him the man fled on foot (generally considered the worse course of action since Cougars can easily outpace us and typically attack prey from behind), leaving his injured friend to escape and seek help. The man's body was later found by trackers from the Washington Dapartment of Fish & Wildlife, who shot and killed the animal. The injured man was airlifted to Harborview Medical Center, where his condition is now described as satisfactory.

Officers from the Washington Department of Fish & Wildlife with the body of a Cougar, which was tracked and shot after killing a cyclist on 19 May 2018. Seattle Times.

Cougars were formerly found throughout the Americas, with the exception of northern Canada and Alaska, however they are now largely restricted to the western parts of North America, where Human populations are lower and more of their original habitat remains. Nevertheless, Cougars are not thought to be a particularly threatened species, with a population of about 2100 adults in Washington State alone, where the population is 'controled' by licenced hunting. 

Attacks on Humans by Cougars are extremely rare, with less than a hundred fatalities recorded in the United States since 1890, and only a single other recorded fatality in Washington State in the last 94 years. The most recent Cougar-related fatality in the US was in New Mexico in 2008.

See also...

http://sciencythoughts.blogspot.co.uk/2018/04/tchadailurus-adei-new-species-of-sabre.htmlhttp://sciencythoughts.blogspot.co.uk/2018/04/woman-attacked-by-leopard-in-rajasthan.html
http://sciencythoughts.blogspot.co.uk/2018/04/german-tourist-attacked-by-leopard-in.htmlhttp://sciencythoughts.blogspot.co.uk/2018/04/german-tourist-attacked-by-leopard-in.html
http://sciencythoughts.blogspot.co.uk/2018/04/eleven-lions-poisoned-in-ugandan.htmlhttp://sciencythoughts.blogspot.co.uk/2018/03/lioness-kills-woman-at-south-african.html

Follow Sciency Thoughts on Facebook.