On Thanksgiving Day , most of us will sit down to enjoy a turkey dinner . The bird also shows up on the table at Christmas . How did we start with the tradition of savoring turkeys during the holidays? They were fresh , cheap , and big enough to feed a group of people . Americans like having large poultry( 家禽 ) for celebrations because they don't need to pay a lot for the birds . Cows were more useful alive than dead , and beef wasn't widely offered until the late 19th century . Chicken was more highly regarded than it is today . Venison( 鹿肉 ) would have been another choice , especially during the 17th and 18th centuries . Eating turkey was also a British holiday custom( 风俗,习惯 ) people brought to the New World . Among the big birds , turkey is the most suitable for Thanksgiving . Turkeys were born in the spring . They spend about seven months eating insects on the farm . By Thanksgiving , they have grown to about 10 pounds . Turkeys are cheaper than geese , which are more difficult to raise , and cheaper by the pound than chickens . Cost is an important factor for holiday shoppers , because people will not prepare just one meal . Thanksgiving Day is the time to bake meal and other types of pies . The foods can last through the winter .