14 JANUARY, 2020 - NAVIGATING BY DOG
Our last post received many comments on "Captain Yuggie", but, almost everyone missed that the picture of me was a click-on video. Always look for embedded/underlined hot links on these pages.
Of all the comments, and questions we field from landlubbers, I believe the #1 subject is about seeing a cat and dog aboard So...fea, for some reason this really shocks people.
In my self assumed role as the So...fea docent, I go on to explain away the “why”, then follow up with the “how” we acquired the animals we have, and I tell a tall sea-tale about being lost at sea and saved by our dog “Bonnie”, the story will not be told here, but the explanation goes like this.
Early Sailors used solar compasses on sunny days and sunstones when it was overcast, the development of the magnetic compass followed, in my post of 2 January I talked about “Time and Navigation”, and today we have GPS.
Dogs and Wolves are very sensitive to the Earth's magnetic field, dogs (like many earth creatures) can define the polarity of this magnetic field.
The ritual we see when a dog circles round and round before settling down to lay a pile, is attributed to a dog's need to align its body along the earths’ magnetic axis and into a true north-south magnetic orientation, just like the needle of a magnetic compass.
Dogs on leashes, however, are not “free” to align themselves into North/South, and can only do so when they are free to choose.
But how do animals and possibly humans sense magnetic fields? Is there some sort of biologic-compass? Other animals (humans too) have been found to exhibit this skill, it is called “magnetoreception”, and it is used by many creatures for orientation and navigation.
Common carp (fish), cows and deer graze and rest aligning themselves with magnetic north, although other factors (wind and sun) also can affect the directions faced by cows.
Lobsters, mole rats, and fruit flies pigeons, bats and monarch butterflies all navigate using the earth’s magnetic fields.
Researchers have verified is that most magnetic field lines in the ocean run the same direction as the coastline, but in some places, these lines change direction abruptly and turn in a direction perpendicular to the coast, and magnetic abnormalities from solar flares and storms may also impact magnetism.
In these magnetically confused places, it is very common to find beached whales, since Whales sense the earth’s magnetic field in order to navigate their long-distances.
So, as the tale goes ... my being constantly afraid of a compass failure, or the GPS not working, we have Bonnie the dog aboard as a “Defecating dog compass”.
Dogs on leashes, however, are not “free” to align themselves into North/South, and can only do so when they are free to choose.
But how do animals and possibly humans sense magnetic fields? Is there some sort of biologic-compass? Other animals (humans too) have been found to exhibit this skill, it is called “magnetoreception”, and it is used by many creatures for orientation and navigation.
Common carp (fish), cows and deer graze and rest aligning themselves with magnetic north, although other factors (wind and sun) also can affect the directions faced by cows.
Lobsters, mole rats, and fruit flies pigeons, bats and monarch butterflies all navigate using the earth’s magnetic fields.
Researchers have verified is that most magnetic field lines in the ocean run the same direction as the coastline, but in some places, these lines change direction abruptly and turn in a direction perpendicular to the coast, and magnetic abnormalities from solar flares and storms may also impact magnetism.
In these magnetically confused places, it is very common to find beached whales, since Whales sense the earth’s magnetic field in order to navigate their long-distances.
So, as the tale goes ... my being constantly afraid of a compass failure, or the GPS not working, we have Bonnie the dog aboard as a “Defecating dog compass”.
If you have more questions… I refer you to “Yuggie” the Captain.