Questions 1 to 3 refer to the following text

    Domestic pigeon (Columba livia) was perhaps the first bird tamed by man. Figurines, mosaics and coins have portrayed the domestic pigeon since at least 4500 B.C. From Egyptian times the pigeon has been important as food. Its role as messenger has a long history.

    Throwbacks among modern domestic pigeons indicate a common ancestor, the rock dove. This tendency is clearly seen in street pigeons in cities everywhere. Many are white, reddish, or checkered like a few of their cousins in racing-pigeon lofts, but most are somewhat narrow-bodied and broad-billed replicas of the blue-gray ancestral form. Street pigeons nest all year-round, on buildings and beneath bridges, where they may be a nuisance with their droppings and transmission of disease. These hardy birds may live to up to 35 years. The three main kinds of domestic pigeons are fliers, fancy breeds raised chiefly for show, and utility breeds, which produce squabs for meat—nestlings taken when 25 to 30 days old and weighing 350 to 700 grams. Utility breeds are known as dual-purpose birds if they are bred for exhibitions.

    Pigeon-raising is a worldwide hobby and business as well There are regular competitions held in several places, such as pigeon racing and singing contests. People also raise pigeons for their meat. It can be made into many delicious dishes.

(Adopted from: http://www.britannica.com/EBchecited/topic/ 168560/domestic-pigeon (March 17. 2020))

How long have pigeons been used as messengers?