New Articles (Page 137)
To stay up to date you can also follow on Mastodon.
π Great Auk
The great auk (Pinguinus impennis) is a species of flightless alcid that became extinct in the mid-19th century. It was the only modern species in the genus Pinguinus. It is not closely related to the birds now known as penguins, which were discovered later by Europeans and so named by sailors because of their physical resemblance to the great auk.
It bred on rocky, remote islands with easy access to the ocean and a plentiful food supply, a rarity in nature that provided only a few breeding sites for the great auks. When not breeding, they spent their time foraging in the waters of the North Atlantic, ranging as far south as northern Spain and along the coastlines of Canada, Greenland, Iceland, the Faroe Islands, Norway, Ireland, and Great Britain.
The great auk was 75 to 85 centimetres (30 to 33 inches) tall and weighed about 5 kilograms (11 pounds), making it the largest alcid to survive into the modern era, and the second-largest member of the alcid family overall (the prehistoric Miomancalla was larger). It had a black back and a white belly. The black beak was heavy and hooked, with grooves on its surface. During summer, great auk plumage showed a white patch over each eye. During winter, the great auk lost these patches, instead developing a white band stretching between the eyes. The wings were only 15Β cm (6Β in) long, rendering the bird flightless. Instead, the great auk was a powerful swimmer, a trait that it used in hunting. Its favourite prey were fish, including Atlantic menhaden and capelin, and crustaceans. Although agile in the water, it was clumsy on land. Great auk pairs mated for life. They nested in extremely dense and social colonies, laying one egg on bare rock. The egg was white with variable brown marbling. Both parents participated in the incubation of the egg for around 6 weeks before the young hatched. The young left the nest site after 2β3 weeks, although the parents continued to care for it.
The great auk was an important part of many Native American cultures, both as a food source and as a symbolic item. Many Maritime Archaic people were buried with great auk bones. One burial discovered included someone covered by more than 200 great auk beaks, which are presumed to be the remnants of a cloak made of great auks' skins. Early European explorers to the Americas used the great auk as a convenient food source or as fishing bait, reducing its numbers. The bird's down was in high demand in Europe, a factor that largely eliminated the European populations by the mid-16th century. Scientists soon began to realize that the great auk was disappearing and it became the beneficiary of many early environmental laws, but this proved ineffectual.
Its growing rarity increased interest from European museums and private collectors in obtaining skins and eggs of the bird. On 3 June 1844, the last two confirmed specimens were killed on Eldey, off the coast of Iceland, ending the last known breeding attempt. Later reports of roaming individuals being seen or caught are unconfirmed. A record of one great auk in 1852 is considered by some to be the last sighting of a member of the species. The great auk is mentioned in several novels, and the scientific journal of the American Ornithological Society was named The Auk (now Ornithology) in honour of the bird until 2021.
Discussed on
- "Great Auk" | 2021-11-13 | 43 Upvotes 27 Comments
π The mysterious broadcast interruption of 1977
The Southern Television broadcast interruption was a broadcast signal intrusion that occurred on 26 November 1977 in parts of southern England in the United Kingdom. The audio of a Southern Television broadcast was replaced by a voice claiming to represent the 'Ashtar Galactic Command', delivering a message instructing humanity to abandon its weapons so it could participate in a 'future awakening' and 'achieve a higher state of evolution'. After six minutes, the broadcast returned to its scheduled programme.
Subsequent investigations showed that the Hannington transmitter of the Independent Broadcasting Authority had rebroadcast the signal from a small but nearby unauthorised transmitter, instead of the intended source at Rowridge transmitting station. The hoaxer was never identified.
The event prompted hundreds of telephone calls from concerned members of the public, and was widely reported in British and American newspapers. These are sometimes contradictory, including differing accounts of the name used by the speaker and the wording of their message.
Discussed on
- "The mysterious broadcast interruption of 1977" | 2021-11-12 | 16 Upvotes 6 Comments
π The art of not being governed
The Art of Not Being Governed: An Anarchist History of Upland Southeast Asia is a book-length anthropological and historical study of the Zomia highlands of Southeast Asia written by James C. Scott published in 2009. Zomia, as defined by Scott, includes all the lands at elevations above 300 meters stretching from the Central Highlands of Vietnam to Northeastern India. That encompasses parts of Vietnam, Cambodia, Laos, Thailand, and Myanmar, as well as four provinces of China. Zomia's 100 million residents are minority peoples "of truly bewildering ethnic and linguistic variety", he writes. Among them are the Akha, Hmong, Karen, Lahu, Mien, and Wa peoples.
Discussed on
- "The art of not being governed" | 2021-11-12 | 10 Upvotes 2 Comments
π Serial-position effect
Serial-position effect is the tendency of a person to recall the first and last items in a series best, and the middle items worst. The term was coined by Hermann Ebbinghaus through studies he performed on himself, and refers to the finding that recall accuracy varies as a function of an item's position within a study list. When asked to recall a list of items in any order (free recall), people tend to begin recall with the end of the list, recalling those items best (the recency effect). Among earlier list items, the first few items are recalled more frequently than the middle items (the primacy effect).
One suggested reason for the primacy effect is that the initial items presented are most effectively stored in long-term memory because of the greater amount of processing devoted to them. (The first list item can be rehearsed by itself; the second must be rehearsed along with the first, the third along with the first and second, and so on.) The primacy effect is reduced when items are presented quickly and is enhanced when presented slowly (factors that reduce and enhance processing of each item and thus permanent storage). Longer presentation lists have been found to reduce the primacy effect.
One theorised reason for the recency effect is that these items are still present in working memory when recall is solicited. Items that benefit from neither (the middle items) are recalled most poorly. An additional explanation for the recency effect is related to temporal context: if tested immediately after rehearsal, the current temporal context can serve as a retrieval cue, which would predict more recent items to have a higher likelihood of recall than items that were studied in a different temporal context (earlier in the list). The recency effect is reduced when an interfering task is given. Intervening tasks involve working memory, as the distractor activity, if exceeding 15 to 30 seconds in duration, can cancel out the recency effect. Additionally, if recall comes immediately after the test, the recency effect is consistent regardless of the length of the studied list, or presentation rate.
Amnesiacs with poor ability to form permanent long-term memories do not show a primacy effect, but do show a recency effect if recall comes immediately after study. People with Alzheimer's disease exhibit a reduced primacy effect but do not produce a recency effect in recall.
Discussed on
- "Serial-position effect" | 2021-11-11 | 33 Upvotes 9 Comments
π Nuclear Gandhi
Nuclear Gandhi is an Internet meme and an urban legend about the video game Civilization. According to the legend, there was a bug in Civilization that eventually forced the pacifist leader Mahatma Gandhi to be extremely aggressive and to use nuclear weapons heavily.
The bug was first mentioned in 2012, two years after the release of Civilization V, and eventually became one of the most recognizable video game glitches; it has been used as an example of integer overflow in computer science and was included in other Civilization games as an easter egg.
In 2020, Sid Meier contradicted the urban legend, stating there had never been a bug of this sort in the original 1991 game. Nuclear Gandhi was first implemented in Civilization V (2010) as a joke.
Discussed on
- "Nuclear Gandhi" | 2021-11-11 | 38 Upvotes 2 Comments
π Unsafe at Any Speed
Unsafe at Any Speed: The Designed-In Dangers of the American Automobile is a non-fiction book by consumer advocate Ralph Nader, first published in 1965. Its central theme is that car manufacturers resisted the introduction of safety features (such as seat belts), and that they were generally reluctant to spend money on improving safety. This work contains substantial references and material from industry insiders. It was a best seller in non-fiction in 1966.
Discussed on
- "Unsafe at Any Speed" | 2021-11-11 | 83 Upvotes 78 Comments
π How trains avoid colliding with each other
Signalling block systems enable the safe and efficient operation of railways by preventing collisions between trains. The basic principle is that a route is broken up into a series of sections or "blocks". Only one train may occupy a block at a time, and the blocks are sized to allow a train to stop within them. That ensures that a train always has time to stop before getting dangerously close to another train on the same line. The block system is referred to in the UK as the method of working, in the US as the method of operation, and in Australia as safeworking.
In most situations, a system of signals is used to control the passage of trains between the blocks. When a train enters a block, signals at both ends change to indicate that the block is occupied, typically using red lamps or indicator flags. When a train first enters a block, the rear of the same train has not yet left the previous block, so both blocks are marked as occupied. That ensures there is slightly less than one block length on either end of the train that is marked as occupied, so any other train approaching that section will have enough room to stop in time, even if the first train has stopped dead on the tracks. The previously-occupied block will only be marked unoccupied when the end of the train has entirely left it, leaving the entire block clear.
Block systems have the disadvantage that they limit the number of trains on a particular route to something fewer than the number of blocks. Since the route has a fixed length, increasing the number of trains requires the creation of more blocks, which means the blocks are shorter and trains have to operate at lower speeds in order to stop safely. As a result, the number and size of blocks are closely related to the overall route capacity, and cannot be changed easily because expensive alterations to the signals along the line would be required.
Block systems are used to control trains between stations and yards, but not normally within the yards, where some other method is used. Any block system is defined by its associated physical equipment and by the application of a relevant set of rules. Some systems involve the use of signals while others do not. Some systems are specifically designed for single track railways, on which there is a danger of both head-on and rear-end collision, as opposed to double track, on which the main danger is rear-end collisions.
Discussed on
- "How trains avoid colliding with each other" | 2021-11-10 | 17 Upvotes 2 Comments
π Fog of War
The fog of war (German: Nebel des Krieges) is the uncertainty in situational awareness experienced by participants in military operations. The term seeks to capture the uncertainty regarding one's own capability, adversary capability, and adversary intent during an engagement, operation, or campaign. Military forces try to reduce the fog of war through military intelligence and friendly force tracking systems. The term has become commonly used to define uncertainty mechanics in wargames.
π A photo on Wikipedia can ruin your life
Discussed on
- "A photo on Wikipedia can ruin your life" | 2021-11-06 | 219 Upvotes 148 Comments