This is a personal opinion question -- your teacher is trying to see if you know the meaning of these idioms. If you have a green thumb, you are a good gardener; if you are all thumbs, you are clumsy.
Not necessarily -- although it is entirely possible that grandpa could have thumbs stained green from picking spinach.
The phrase "green thumb" originated from the idea that people who have a natural talent for gardening have hands that appear green from handling plants. Having a green thumb means that someone is skilled at growing plants and maintaining a garden successfully.
Every successive generation would still continue to have thumbs because though you removed your thumb, you did not remove the genetic material that causes the thumb to grow in the first place. To cause you future generations to lack thumbs, you would have to alter the genetic material that goes into forming the sperm or ovum.
the saying "green thumb" means someone who, not literally, has a green thumb because they like gardening. When growing tobacco, farmers remove the flowers from the crops in order to increase the size and weight of the leafs. This process, known as "topping," is standard practice even today. In early colonial America, when tobacco was the major cash crop, farmers would hand-pick the flowers using their thumbnails to cut the stem. After a while, the farmer's thumb would be stained green. Hence the term, Green Thumb.
If a person's thumb literally turns green, it would be a symptom of decay. Green is not a good color for the human body.
An Alien or martian
The signal of the people or Caesar for death or life is a little fuzzy in history, but almost surely was not thumbs up or thumbs down. There is good evidence that the death signal was a thumb straight out sideways, and the signal for life was the thumb placed over the extended index finger.
From my opinion, and I have the game, it is a FANTASTIC game. I would give it a thumb and 2 fingers. No, 3 thumbs and 4 fingers.
If you are a gardener and you are constantly nipping out laterals or light pruning you do it with the thumbnail. You only get a green thumb if you already have the talent.
Humans (if being considered) do have the the most effective opposable thumbs. Next in line would be our close relative the chimpanzees
The goddess Demeter would be known for a green thumb, as she is the Goddess of Agriculture. She is also the mother of Persephone, fathered by Zeus.
We have no record of Julius Caesar ever ordering a gladiator's death, although it could have been possible as he sponsored gladiatorial combats. Remember that there is controversy about the "thumbs" business. Hollywood would have you believe that thumbs down meant death but historians believe that it was a turning of the thumb that signaled the death blow. To explain, the thumb was a symbol for the sword. If the editor of the games turned his thumb up, it meant "put up your sword" or don't fight. If he turned his thumb sideways, it meant "run him through" or kill as death wounds are generally given with the sword in a stabbing or straight position.We have no record of Julius Caesar ever ordering a gladiator's death, although it could have been possible as he sponsored gladiatorial combats. Remember that there is controversy about the "thumbs" business. Hollywood would have you believe that thumbs down meant death but historians believe that it was a turning of the thumb that signaled the death blow. To explain, the thumb was a symbol for the sword. If the editor of the games turned his thumb up, it meant "put up your sword" or don't fight. If he turned his thumb sideways, it meant "run him through" or kill as death wounds are generally given with the sword in a stabbing or straight position.We have no record of Julius Caesar ever ordering a gladiator's death, although it could have been possible as he sponsored gladiatorial combats. Remember that there is controversy about the "thumbs" business. Hollywood would have you believe that thumbs down meant death but historians believe that it was a turning of the thumb that signaled the death blow. To explain, the thumb was a symbol for the sword. If the editor of the games turned his thumb up, it meant "put up your sword" or don't fight. If he turned his thumb sideways, it meant "run him through" or kill as death wounds are generally given with the sword in a stabbing or straight position.We have no record of Julius Caesar ever ordering a gladiator's death, although it could have been possible as he sponsored gladiatorial combats. Remember that there is controversy about the "thumbs" business. Hollywood would have you believe that thumbs down meant death but historians believe that it was a turning of the thumb that signaled the death blow. To explain, the thumb was a symbol for the sword. If the editor of the games turned his thumb up, it meant "put up your sword" or don't fight. If he turned his thumb sideways, it meant "run him through" or kill as death wounds are generally given with the sword in a stabbing or straight position.We have no record of Julius Caesar ever ordering a gladiator's death, although it could have been possible as he sponsored gladiatorial combats. Remember that there is controversy about the "thumbs" business. Hollywood would have you believe that thumbs down meant death but historians believe that it was a turning of the thumb that signaled the death blow. To explain, the thumb was a symbol for the sword. If the editor of the games turned his thumb up, it meant "put up your sword" or don't fight. If he turned his thumb sideways, it meant "run him through" or kill as death wounds are generally given with the sword in a stabbing or straight position.We have no record of Julius Caesar ever ordering a gladiator's death, although it could have been possible as he sponsored gladiatorial combats. Remember that there is controversy about the "thumbs" business. Hollywood would have you believe that thumbs down meant death but historians believe that it was a turning of the thumb that signaled the death blow. To explain, the thumb was a symbol for the sword. If the editor of the games turned his thumb up, it meant "put up your sword" or don't fight. If he turned his thumb sideways, it meant "run him through" or kill as death wounds are generally given with the sword in a stabbing or straight position.We have no record of Julius Caesar ever ordering a gladiator's death, although it could have been possible as he sponsored gladiatorial combats. Remember that there is controversy about the "thumbs" business. Hollywood would have you believe that thumbs down meant death but historians believe that it was a turning of the thumb that signaled the death blow. To explain, the thumb was a symbol for the sword. If the editor of the games turned his thumb up, it meant "put up your sword" or don't fight. If he turned his thumb sideways, it meant "run him through" or kill as death wounds are generally given with the sword in a stabbing or straight position.We have no record of Julius Caesar ever ordering a gladiator's death, although it could have been possible as he sponsored gladiatorial combats. Remember that there is controversy about the "thumbs" business. Hollywood would have you believe that thumbs down meant death but historians believe that it was a turning of the thumb that signaled the death blow. To explain, the thumb was a symbol for the sword. If the editor of the games turned his thumb up, it meant "put up your sword" or don't fight. If he turned his thumb sideways, it meant "run him through" or kill as death wounds are generally given with the sword in a stabbing or straight position.We have no record of Julius Caesar ever ordering a gladiator's death, although it could have been possible as he sponsored gladiatorial combats. Remember that there is controversy about the "thumbs" business. Hollywood would have you believe that thumbs down meant death but historians believe that it was a turning of the thumb that signaled the death blow. To explain, the thumb was a symbol for the sword. If the editor of the games turned his thumb up, it meant "put up your sword" or don't fight. If he turned his thumb sideways, it meant "run him through" or kill as death wounds are generally given with the sword in a stabbing or straight position.