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Posts Tagged ‘science’

The Monarch Butterfly’s Spring Migration

April 9, 2014 6 comments

File:Monarch Butterfly Danaus plexippus on Echinacea purpurea 2800px.jpg

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The time is approaching for eastern Monarch butterflies (Danaus plexippus) to return to the U.S. east coast from their wintering grounds in Mexico: a more beautiful visitor is hard to imagine. Though the population of the Monarch has declined significantly in recent years, a decline linked to several changes in the butterfly’s environment, the MB is not yet listed as endangered. Fortunately, several organizations are at work trying to protect the butterflies; RT offers links to a couple of them, Monarch Watch and Monarch Butterfly Fund. As is so often the case, the status of the most vulnerable members of a community is a good indicator of the community’s overall health.   RT

Photograph: A Monarch Butterfly on a Purple Coneflower (2007). Author: Derek Ramsey (Ram-Man). WikiCmns; License: GNU Free Documentation License, Version 1.2 only. This image was selected as picture of the day on English Wikipedia, August 27, 2008.

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A Leaf Hair

February 11, 2014 1 comment

File:Müürlooga (Arabidopsis thaliana) lehekarv (trihhoom) 311 0804.JPG

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RT has to say he doesn’t have the faintest idea what this is, but wow! Some worthwhile research is in the offing, he’s willing to wager!

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PhotoScanning electron micrograph of trichome: a leaf hair of thale cress (Arabidopsis thaliana). Author: Heiti Paves. Uploaded as part of the Estonian Science Photo Competition. WikiCmns; CC 3.0 Unported.

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UV Earth

January 5, 2014 2 comments

File:Earthinuvfrommoon.jpg

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Here’s an eye-catcher to start the year with: the Earth, taken in ultraviolet light from the surface of the Moon. Open your eyes, folks…   RT

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Photo: Earth in Ultraviolet Light from the Moon’s Surface. NASA. Public Domain.

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Lake Victoria Dreaming

December 28, 2013 Leave a comment

File:Luo People Fishing.jpg

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Here are some stats to accompany the above dream-like photo: Africa’s Lake Victoria, the largest tropical lake in the world, is also the second largest lake in the world by surface area (only Lake Superior is larger). The lake is famous for its large number of cichlid species, these fish having adapted to the lake’s numerous ecological niches–but many have been driven extinct (or nearly so) by introduced exotic fish species, and in particular, the Nile perch.

The Lake Victoria basin is one of the most densely populated rural areas in the world, and raw sewage dumped into the lake poses a significant threat. LV supports Africa’s largest inland fishery. In 2006, the lake produced a harvest of Nile perch valued at U.S. $250 million. In 2004, the fishery employed in excess of 150,000 fishermen.

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PhotoLuo People Fishing in Lake Victoria (2009). Author: DancingPope. WikiCmns; CC 2.0 Generic.

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Local and Global: The Black Plague & All That

October 27, 2013 3 comments

File:World distribution of plague 1998.PNG

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Revolutions happen when nobody is looking; the same might be said of disasters. The map above is none too reassuring.  Before they arrive at your doorstep, problems are easy to ignore.

Yersenia Pestis. This was the spark that set the dry tinder in Medieval Europe blazing in the 14th century and cost the continent somewhere around half its population, bringing the Middle Ages to an end in the process. YP, the bacterium that caused the Black Plague, devastating western Asia and Europe between 1347 and 1351, remains loose in the wild today and could be used as a biological weapon.  The disaster that ushered in the Modern Era stands ready to create another phase shift.

Couldn’t we find a better way to dis-invest in our current system and take history to the next level?

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It’s not like RT’s schedule is full of free time to explore new subjects with, but here is a topic, first raised by Aubrey in one of her comments in these pages, that cannot really be ignored. Just why hasn’t humankind gotten around to creating some kind of global coordination on global threats?

Certainly, one of the reasons has to do with reconciling local and global considerations, a theme with far-ranging implications. RT will be exploring some of these in future posts, possibly tying them to the cultural issues that form the core of this blog. Climate change, unchecked threats to human health, nuclear arms, abject poverty amid staggering wealth–just why can’t we see ourselves as a single community?     RT

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Map: World Distribution of Plague, 1998. Centers for Disease Control and Prevention. WikiCmns; Public Domain.

Darwin’s Fox

October 6, 2013 Leave a comment

File:Pseudalopex fulvipes.jpg

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The critically endangered Darwin’s Fox (Lycalopex fulvipes) is found only on the Chiloe Islands and the nearby Chilean mainland. Although Lycalopex is a canine, it is not a fox and only distantly related to wolves–and yes, it was first described by Charles Darwin in 1834, during his renowned voyage aboard the Beagle.

With a “vast” diet, DF nonetheless depends on Chiloe’s primary rainforest; the forest is being cut on the islands. More important, however, may be the introduction of wild dogs into the area. About 320 Darwin Foxes live in the wild, according to the World Conservation Union.

RT

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RT’s Related Posts: 1) Lake Titicaca Water Frog; 2) Mediterranean Vacation: Lost Landscapes

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Photo: A male Darwin’s fox in western coast of Chiloe, Chile; Author: Fernando Borques (uploaded by Lin linao). WikiCmns; Public Domain.

Voyager 1 Enters Interstellar Space!

September 14, 2013 5 comments

File:Voyager.jpg

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NASA has confirmed it: launched in 1977, Voyager 1 entered interstellar space in August 2012. Another giant leap for mankind…  RT

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Photo: Voyager 1; NASA. WikiCmns; Public Domain.

Cygnus Loop Supernova

August 31, 2013 7 comments

File:Cygnus Loop Supernova Blast Wave - GPN-2000-000992.jpg

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Whoa, what happened here? Five to ten thousand years ago, a massive star exploded, sending out shock-waves in all directions, creating the Cygnus Loop. The blast shell is currently expanding at 370,000 mph and emits energy across the electromagnetic spectrum: radio, visible, x-ray, and ultra-violet. Some of the ejecta material, however, is travelling faster: the violet streak of light near the top of the image marks the path of a knot of gases moving at nearly 3 million mph. This image is a combination of three photographs: one capturing green light (hydrogen atoms), one, blue light (oxygen atoms); and the last, red light (sulfur atoms). 

The visible part of the Swan Loop is called the Veil Nebula, and was discovered by William Herschel in 1784.

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RT’s Related Posts: 1) Guest Star.

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Photo: Cygnus Loop Supernova Blast Wave (1993); Hubble Space Telescope. Author: NASA, J.J. Hester Arizona State University. WikiCmns; Public Domain.

Hereford Mappa Mundi

August 22, 2013 1 comment

File:Hereford Mappa Mundi 1300.jpg

RT has decided that now is the time to catch up on work that has fallen by the way. This post is occasioned by a request from fellow-blogger Calmgrove. And RT has to agree: this is a remarkable map.

The Hereford Mappa Mundi (Hereford World Map) is the largest medieval map extant; it measures 62″ x 52.” Drawn on vellum with ink, it depicts 420 towns, 15 Biblical events, 33 animals and plants, 32 people, and five scenes from classical mythology, but does not reflect the full cartographic knowledge of its time; the Caspian Sea, for instance, connects to the encircling ocean (upper left). This in spite of William of Rubruk‘s having reported it to be landlocked in 1255.

The map is still exhibited in the building where it was initially displayed: Hereford Cathedral in Hereford, England.

The HMM follows the T and O Pattern, that is, its representation of the world contains a T shape within a circle, reflecting the work of Beatus of Liebana, an 8th-century Spanish monk. Jerusalem is located at the center of the map, but note that the HMM also depicts the Indus and Ganges rivers. Noah’s ark and the Land of Gog and Magog are indicated, but the map may also include Sri Lanka. As seems to be the case with ancient maps of the West, the Mediterranean Sea is the most accurately drawn part of the map.

RT will close by noting the date of the HMM: 1285; this map was created at the end of the Middle Ages, and RT cannot help but wonder at the explosion of geographic knowledge that was soon to transform world maps. His research leads RT to believe that this knowledge began filtering into Europe sooner than often supposed; he has found one or two 14th-century maps that are remarkable for their accuracy. But more on that later…   RT

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RT’s Related Posts: 1) Metaphysical Maps; 2) Tabula Peutingeriana.

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Map: Hereford Mappa Mundi (c. 1285 A.D.); WikiCmns; Public Domain.

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The Three Gorges Dam

August 21, 2013 Leave a comment

File:Drei-Schluchten-Damm (Jangtse).jpg

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The statistics are insane: China’s Three Gorges Dam, completed in 2012, is the largest hydroelectric project in the world. The dam has an installed capacity of 20.3 billion watts of electricity, the largest hydro-electrical capacity in the world, ahead of the Itaipu Dam in Brazil and Paraguay (14 billion watts). The dam wall is 594 ft. tall and stretches 7,661 ft. (1.45 mi.). The TGD is the world’s largest by holding capacity (nearly 32 billion acre-feet) and has created a reservoir 370 miles long (for the record, that’s longer than Lake Superior) with an average elevation of 570 ft. above sea level.

The electricity generated by Three Gorges will go a long way to shutting down China’s coal-fired power plants, notorious for the air pollution they caused, and the reservoir should finally end the devastating floods that people along the lower Yangtze River have endured throughout history (300,000 people killed during the 20th century alone).

The problems with the dam have been manifold: 1) silting (addressed now by China’s massive forest-planting program); 2) pollution of the reservoir; 3) landslides along the reservoir shoreline; 4) the relocation of more than a million former residents along the river; 5) the functional extinction of the Yangtse River Dolphin (the Baiji); and 6) the loss of undiscovered archaeological sites along the river.

Is the TGD worth it? Would the construction of a series of smaller dams along tributaries have provided the same benefits without the ecological problems? RT guesses that wiser is not always better: the appeal of the Three Gorges Dam to the imagination is surely part of this calculation, and the scope of the project speaks to our sense of drama. RT has a hunch that this grand gamble on the part of the Chinese government will pay off.

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Photo: Three Gorges Dam (Yangtze), Author: gugganij. WikiCmns; CC 1.0 Generic.

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