Read Online Are Lobsters Ambidextrous? by David Feldman - Free Book Online
Authors: David Feldman
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is “jumped” upward.
Halmos reports that tower cranes have largely eliminated the need for elevators (known as “skips”) and the lifting of loads from the ground by mobile cranes. “The tower crane operator can see not only what he’s picking up, but can spot the loadalmost anywhere on the job, without a lot of elaborate signaling.”
Submitted by Laura Laesecke of San Francisco, California. Thanks also to Paula Chaffee of Utica, Michigan; Lawrence Walters of Gurnee, Illinois; James Gleason of Collegeville, Pennsylvania; and Robert Williams of Brooklyn, New York .
What is “single-needle” stitching, and why do we have to pay more for shirts that feature it?
You’d think that at fifty dollars or more a pop, shirtmakers could afford another needle or two. Actually, they can.
“Regular” shirts are sewn with one needle working on one side of a seam and another needle sewing the other side. According to clothing expert G. Bruce Boyer, this method is cheaper and faster but not as effective because “Seams sewn with two needles simultaneously tend to pucker. Single-needle stitching produces flatter seams.”
Submitted by Donald Marti, Jr., of New York, New York .
Why do dogs wiggle their rear legs when scratched on their belly or chest?
Maybe there is a Labrador retriever out there writing a book of canine Imponderables, trying to answer the mystery: Why do humans kick their legs up when you tap the area below their kneecaps? The leg wiggling of dogs is called the scratch reflex, the doggy equivalent of our involuntary knee-jerk reflex (or, as it is known to doctors, patellar reflex).
Anatomist Robert E. Habel, of Cornell University’s College of Veterinary Medicine, wrote Imponderables that the scratch reflex allows veterinarians to diagnose neurological problems in dogs:
Because the same spinal nerves pass all the way down to the midline of the chest and abdomen, you can stimulate the scratch reflex anywhere from the saddle region to the ventral midline. You can test the sensory function of many spinal nerves and the motor function of the nerves to the hind limb (they don’t wiggletheir forelimbs). If the dog moves the hind limb, it means the spinal cord is not severed between the origin of the nerve stimulated and the origins of the lumbar through first sacral nerves, but the cord may be injured above the level stimulated.
A dog is not necessarily injured if it doesn’t exhibit the scratch reflex. In fact, Dr. Habel reports that his hound doesn’t respond at all.
What function does the scratch reflex serve? Nobody knows for sure, but that doesn’t stop dog experts from theorizing. Breeder and lecturer Fred Lanting believes that the wiggling might be a “feeble or partial attempt” to reach the area where you are scratching. Just as scratching ourselves sometimes causes the itch to migrate to other parts of the body, Lanting believes that scratching a dog may cause itchiness in other regions.
Dog expert and biology instructor Jeanette Hayhurst advances an even more fascinating theory, which is that the scratch reflex might help dogs survive. The movement of the back legs during the scratch reflex resembles the frantic movements of a puppy learning to swim. The scratch reflex might be an instinctive reaction to pressure on the abdomen, the method nature provides for a puppy to survive when thrown into the water. Newborn pups also need to pump their back legs in order to crawl to reach their mother’s teat.
We’d like to think that our human knee-jerk reflex might also have a practical purpose, but we’ll leave it to the dogs to solve this particular mystery.
Submitted by Shane Ellis of Mammoth Lakes, California. Thanks also to Kurt Pershnick of Palatka, Florida; Sonya Landholm of Boone, North Carolina; Alina Carmichael and Pat Kirkland of Lake St. Louis, Missouri; Sherry-Lynn Jamieson of Surrey, British Columbia; Sofi Nelson of Menomonie,
Halmos reports that tower cranes have largely eliminated the need for elevators (known as “skips”) and the lifting of loads from the ground by mobile cranes. “The tower crane operator can see not only what he’s picking up, but can spot the loadalmost anywhere on the job, without a lot of elaborate signaling.”
Submitted by Laura Laesecke of San Francisco, California. Thanks also to Paula Chaffee of Utica, Michigan; Lawrence Walters of Gurnee, Illinois; James Gleason of Collegeville, Pennsylvania; and Robert Williams of Brooklyn, New York .
What is “single-needle” stitching, and why do we have to pay more for shirts that feature it?
You’d think that at fifty dollars or more a pop, shirtmakers could afford another needle or two. Actually, they can.
“Regular” shirts are sewn with one needle working on one side of a seam and another needle sewing the other side. According to clothing expert G. Bruce Boyer, this method is cheaper and faster but not as effective because “Seams sewn with two needles simultaneously tend to pucker. Single-needle stitching produces flatter seams.”
Submitted by Donald Marti, Jr., of New York, New York .
Why do dogs wiggle their rear legs when scratched on their belly or chest?
Maybe there is a Labrador retriever out there writing a book of canine Imponderables, trying to answer the mystery: Why do humans kick their legs up when you tap the area below their kneecaps? The leg wiggling of dogs is called the scratch reflex, the doggy equivalent of our involuntary knee-jerk reflex (or, as it is known to doctors, patellar reflex).
Anatomist Robert E. Habel, of Cornell University’s College of Veterinary Medicine, wrote Imponderables that the scratch reflex allows veterinarians to diagnose neurological problems in dogs:
Because the same spinal nerves pass all the way down to the midline of the chest and abdomen, you can stimulate the scratch reflex anywhere from the saddle region to the ventral midline. You can test the sensory function of many spinal nerves and the motor function of the nerves to the hind limb (they don’t wiggletheir forelimbs). If the dog moves the hind limb, it means the spinal cord is not severed between the origin of the nerve stimulated and the origins of the lumbar through first sacral nerves, but the cord may be injured above the level stimulated.
A dog is not necessarily injured if it doesn’t exhibit the scratch reflex. In fact, Dr. Habel reports that his hound doesn’t respond at all.
What function does the scratch reflex serve? Nobody knows for sure, but that doesn’t stop dog experts from theorizing. Breeder and lecturer Fred Lanting believes that the wiggling might be a “feeble or partial attempt” to reach the area where you are scratching. Just as scratching ourselves sometimes causes the itch to migrate to other parts of the body, Lanting believes that scratching a dog may cause itchiness in other regions.
Dog expert and biology instructor Jeanette Hayhurst advances an even more fascinating theory, which is that the scratch reflex might help dogs survive. The movement of the back legs during the scratch reflex resembles the frantic movements of a puppy learning to swim. The scratch reflex might be an instinctive reaction to pressure on the abdomen, the method nature provides for a puppy to survive when thrown into the water. Newborn pups also need to pump their back legs in order to crawl to reach their mother’s teat.
We’d like to think that our human knee-jerk reflex might also have a practical purpose, but we’ll leave it to the dogs to solve this particular mystery.
Submitted by Shane Ellis of Mammoth Lakes, California. Thanks also to Kurt Pershnick of Palatka, Florida; Sonya Landholm of Boone, North Carolina; Alina Carmichael and Pat Kirkland of Lake St. Louis, Missouri; Sherry-Lynn Jamieson of Surrey, British Columbia; Sofi Nelson of Menomonie,
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