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I have combined many of the pictures from this blog
Human ears (left) with stereo capability can hear a broad range of sound but other animals have more complex and sensitive ears and can hear a wider or different range of frequencies. This young antelope (middle) has large ears which it can move to focus sounds. Bats (right) depend on their antennae-like ears to determine distances using echolocation, i.e. bouncing changing sounds off of objects.
Human smell (left) is one of our weakest senses, far surpassed by dogs (middle) who are 10,000 times more sensitive and bears (right) whose ability to smell is 7 times more sensitive than dogs.
"The platypus can determine the direction of an electric source, perhaps by comparing differences in signal strength across the sheet of electroreceptors. This would explain the characteristic side-to-side motion of the animal's head while hunting." (commons.wikimedia.org)But defining and describing animal senses is only part of how senses operate in a living organism, which brings us to the classic subjective/objective debate. While the stimuli that a sense perceives is clearly outside the organism, the way that the stimuli is interpreted and acted on is determined by the animal, i.e. it is subjective.
"Almost all higher order features of vision are influenced by expectations based on past experience. This characteristic extends to color and form perception...to face and object recognition...and to motion and spatial awareness..." http://www.brainhq.com/brain-resources/brain-facts-myths/how-vision-works
Eyesight is probably the strongest human sense (left) with full color stereoscopic vision and a remarkable ability for edge detection. But other animals such as eagles (middle) have 3.6 times the human visual acuity. Some insects (right) have a compound eye with a fisheye view (180 degrees) of the world that can see objects in focus both near and far at the same time.
"Until now, scientists believed that only a couple of brain areas mediate facial recognition. However scientists have discovered that an entire network of cortical areas work together to identify faces.'This research will change the types of questions asked going forward because we are not just looking at one area of the brain," said Nestor...lead author of the study. "Now, scientists will have to account for the system as a whole...:" http://www.sciencedaily.com/releases/2011/05/110531121319.htmThis means a sound that is objectively 261.6 Hz and 70 decibels will have a different meaning for a human than for a mouse, for example. This sound is middle C or a musical note played at the normal volume on a radio. To a human being it would carry a musical meaning, perhaps reminding him or her of a sweet song but to a mouse it might be a warning that a human was nearby.
"This ability to hold on to a piece of information temporarily in order to complete a task is specifically human. [ED: my emphasis] It causes certain regions of the brain to become very active, in particular the pre-frontal lobe. This region, at the very front of the brain, is highly developed in humans. It is the reason that we have such high, upright foreheads, compared with the receding foreheads of our cousins the apes. Hence it is no surprise that the part of the brain that seems most active during one of the most human of activities [ED: short term memory] is located precisely in this prefrontal region that is well developed only in human beings."Perhaps the most extreme example of short-term memory is a chess master who can explore several possible solutions mentally before choosing the one that will lead to checkmate." SHORT-TERM MEMORY': McGill University, Montreal, Canada
QUOTE FROM WIKIPEDIA ABOUT HUMAN SENSES
Perception not based on a specific sensory organ
Chronoception refers to how the passage of time is perceived and experienced. Although the sense of time is not associated with a specific sensory system, the work of psychologists and neuroscientists indicates that human brains do have a system governing the perception of time, composed of a highly distributed system involving the cerebral cortex, cerebellum and basal ganglia.
NOTE: It is quite significant that the most used noun in the English language is *time* according to the Concise Oxford English Dictionary, with the words year, day and life not far behind. While I can document this for English, I don't have the resources to document this in other languages -- but I assume that time is the most used noun in other languages as well.While we cannot go back tens of thousands of years to reconstruct how a long term sense of time came about, there is perhaps another way to understand how it developed. When our children are young, they only live in the moment, but over years, especially as a result of education, they learn a long term sense of time. This process occurs starting with childhood, continues until adulthood and can be observed and studied.
Measures of performance on tests of working memory increase continuously between early childhood and adolescence; theorists have argued that the growth of working-memory capacity is a major driving force of cognitive development.
During the twenty year 'long childhood' of humans, young people learn their culture's expectations about time. While I will write a full blog about this, suffice it to say students in school learn about time more than any other subject. They learn to arrive on time, to not be late to each of their classes and to manage time such as doing their homework or studying for a final exam. These time demands become more stringent as a student gets older.
"People can time-travel cognitively because they can remember events having occurred at particular times in the past (episodic memory) [ED: e.g. the sense of when] and because they can anticipate new events occurring at particular times in the future. The ability to assign points in time to events arises from human development of a sense of time and its accompanying time-keeping technology." William Roberts, Are Animals Stuck in Time?
Take, for example, this very simple sentence that anyone of us might say -- yet which is extremely sophisticated:"When I finish this job in about an hour, I will be done for the day."This sentence which includes past, present, future and future perfect (a past that is in the future at the present time but will be past at a future point), is something we humans understand, but cannot be understood by any other animal.
While we have all learned to live with clocks and show up on time, our personal sense of 'when' is not tied to man-made artificial timekeeping.
"Sharks smell through a pair of nostril-like holes, called nares...When its olfactory sensors detect the odor of a potential catch, the shark will turn into the current that is carrying the chemical. In addition, a shark's olfactory talents are so refined that it can often tell which of its nares is getting the stronger scent signal, guiding it even more precisely toward its prey." http://www.pbs.org/kqed/oceanadventures/episodes/sharks/indepth-senses.html
Understanding other types of animal senses has led to major scientific breakthroughs in the past, such as the development of radar which came about in part due to the study of how bats navigated in the dark and which also led to the development of sonar and ultrasound technology. (commons.wikimedia.org)
Because humans have hands that are free along with good vision,eye-hand skills have been critical to the creation of civilization. (commons.wikimedia.org)
Detail: "The creation of man by Prometheus. Marble relief, Italy, 3rd century CE." Louvre Museum, Paris, France. (commons.wikimedia.org)
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NOTE: I did not like the translations of this poem in English, so with apologies to Cyprian Norwid -- since I write poetry myself and have translated poems in French and Spanish -- I freely improvised taking the best lines/words from four different English translations, then added my own ideas and made my own English version. Here are the links to the various English translations that I found plus the original poem in Polish.    [5 -- the original Polish]
"Wajda [ED: director of Ashes and Diamonds] has frequently remarked upon the special role of the artist in Polish culture: the political conscience of a nation during long periods when politics could not be openly and honestly discussed. He has also noted that Polish artists have fulfilled themselves not only in their art but in their participation in history. [ED: such as Paderewski, a famous pianist, who also became prime minister]."http://www.ucis.pitt.edu/eehistory/H200Readings/Topic3-R4.html
My Point Is ThisFor most of history people had a clear view of the stars and the moon which were a point of reference -- a nightly clock and a monthly, seasonal and yearly calendar. Also because the cities were not lighted, people's eyes were often well adjusted to seeing in the dark -- and so the night sky was an ever present background. NOTE: This fact is critical because eyes that have adjusted to darkness can see many more stars.
In the fictional historic worlds created by Hollywood, light seemed to be everywhere. So in this screenshot from the trailer for the 1951 film Quo Vadis (left) Deborah Kerr was seen in light that illuminated the background and delicately highlighted her face -- all from Roman lamps! In reality the light was probably more like the picture on the right, where the background was dark and her face was lit in a much starker manner. (commons.wikimedia.org) NOTE: The picture on the right is my own reworking of the original trailer screenshot and my best guess about the actual lighting in ancient Rome.
Depictions of historic time periods often show bright lamps and candles that illuminate wide areas. Yet this is not accurate. While this may seem like a minor point, it is not. As a photographer, I know how light operates. Light diminishes according the to square of distance, which means that light falloff is quite rapid.
Quote from Wikipedia: "The intensity (or illuminance or irradiance) of light or other linear waves radiating from a point source (energy per unit of area perpendicular to the source) is inversely proportional to the square of the distance from the source; so an object (of the same size) twice as far away, receives only one-quarter the energy (in the same time period)." (commons.wikimedia.org)
"In 1667, Paris became the first city in the world to light its streets, using wax candles in glass lamps...by the end of the century, more than 50 of Europe's major towns and cities were lit at night." Quoted from the URL next.While street lighting began in Paris in 1667, it was only from November to March and only on main streets. Yet by 1700 it had been extended to nine months of the year. The idea of street lighting with candles spread to other cities, yet many only lit their lamps on moonless nights. And although candles helped, the general lighting was still quite dim.
A painting of Frederick the Great of Prussia playing the flute. While the best quality approx. 50 candles -- pictured here in the mid-18th century -- were a lavish expense, the total light output was about as much as one 100 watt incandescent bulb of today. (commons.wikimedia.org)
Although there were street lamps in major cities, they were quite faint. London was so dim in the early Victorian era that boys called link-boys (bottom left) made a living by carrying a candle or torch at night to guide people to their destination. The picture above is of a woman arriving home in her 'sedan chair' -- with a street lamp behind her, a footman with a candle and a link-boy with a torch. Picture of contemporary London life from Dicken's Pickwick Club 1837. (commons.wikimedia.org)
Another unrealistic painting. The bright light for this well lit coffee house comes from only a couple of candles. (commons.wikimedia.org)
Gas lighting in Paris in 1889. Gas lighting became common by the end of the 19th century. Yet although brighter than candles, it was relatively dim compared to today's electric lights and also burned in the red end of the spectrum. So the stars and the night sky were still visible in the 19th century and were an integral part of people's lives up until a few years ago. Countrywide electric lighting did not take over until after World War II. (commons.wikimedia.org)
Google translation from the French Wikipedia entry about light pollution: With the emergence and rapid spread of the light bulb and the electric network, public lighting became widespread in the world, producing in the 1940s an early bright halo, reported by astronomers as being a hindrance to their work. The concept of "light pollution " was born (under that name) in the late 1980s. http://fr.wikipedia.org/wiki/Pollution_lumineuse
Here is a quote from a discussion group about why astronomy is not important:
Science & Mathematics > Astronomy & Space
I think that most people are focused on a few things that are critical to their own existence. For some, that means family; for others, a career. In those specific areas, they are generally articulate and knowledgeable...What this means is that astronomy is a backwater in the knowledge pool for most folks. They could understand it if it was a priority, but it's not.
If we wonder why so many urban people today feel alienated, one reason could be that they are no longer in touch with the cycles of the Earth and the Sun and the natural sense of time told to us by the stars.
Coney Island's Luna Park, an amusement park in New York City at the beginning of the 20th century (1903), when electric light was still a novelty. (commons.wikimedia.org)
NYC around 1935 from the top of a construction site. (commons.wikimedia.org)
Times Square today in NYC. (commons.wikimedia.org)
Satellite composite of lights at night on the Earth. (commons.wikimedia.org)
Map showing light pollution in Europe: red is the most, yellow next. (commons.wikimedia.org)
The same region of sky near a town of about 200 people (top) and near a city of about 400,000 people (bottom) in Utah, USA. The light pollution near any urban area now blots out much of the sky. (commons.wikimedia.org)