Ask mr Brain...all will be explained
Why is the year Jesus Christ was born called 1 AD? SHIRLEY AU Yuen Long Merchants Association Secondary School The term AD originally meant anno Diocletiani, meaning the year of the Emperor Diocletian, who ruled the Roman Empire from 284 until 305. Dates were calculated from the year he became emperor, so our modern 284 was, to the Romans, 1 AD.
Diocletian was famous for two things - dividing the Roman Empire and persecuting Christians.
The Diocletiani system of calculating dates lasted until the 6th cen tury. Then a monk and scholar called Dionysius Exiguus from Scythia (now part of Ukraine) decided to change the calendar in honour of Christ. He decided that years should be calculated from the birth of Christ, so the year 248 anno Diocletiani became 532 anno Domini (the year of Our Lord).
Most historians believe Dionysius miscalculated the birth of Christ. It is now generally believed that Christ was born between 6 BC and 4 BC. He was also responsible for setting Christmas as December 25. Despite these mistakes, his is the calendar we still use to this day.
It is rather ironic that the initials which originally were in honour of the emperor who carried out the last large scale persecution of Christians were adopted in honour of Christ.
Why do animals follow people's instructions? ALICE CHER Yuen Long Merchants Association Secondary School Some animals that have been domesticated can be trained to follow people's instructions. One such animal, the dog is descended from wild wolves and is thought to be the first animal to have been domesticated. Dogs have been selectively bred throughout the centuries to perform tasks such as hunting and retrieving game, guarding property and being companions for humans.
In modern times they have also been trained to be guides for the blind and to detect drugs and bombs for law enforcers.
Dogs are pack animals that live in social groups. They have a hierarchy whereby members lower down in the group are submissive to those higher up and more dominant. Humans take advantage of the dog's natural tendency to submit to the 'top dog'. If a dog's owner can rein force the idea that he is the leader, the dog will be more easily controlled.
To train animals, people use a mixture of rewards for correct behaviour and punishment for incorrect behaviour.
Trainers who have worked with dolphins say using rewards for positive behaviour is quite effective. The process also requires a lot of patience, the building up of trust and rapport between the animal and the trainer, careful observation and intuition.
Although rewards include food, this is not the only enticement to get dolphins to perform their acrobatics. Other rewards include giving them their favourite toys, play sessions, rubdowns and time off. Dolphins also appear to perform great feats of gymnastics for their own sheer enjoyment.
