Sheep

From Wikipedia
Flock of sheep

A sheep is a wooly four legged animal. Female sheep are called ewes. Male sheep are called rams. Babies are called lambs.

Sheep follow others blindly. This is why people are sometimes called sheep. It means that a person follows a group of people. This can be because they trust the group. Or it can be because they are not thinking for themself. This can be good if the group leads to something positive (like the group of sheep being led to grass). It can be bad if the group leads the other sheep to something negative.

The way sheep follow each other is so reliable that there are special names for the different roles sheep play in a flock. The sheep that is furthest away from the others is called the outlier, a term also used in statistics. This sheep is willing to go out further away from the safety of the flock to graze, but takes a chance that a predator like a wolf will attack it first, because it is alone. Another sheep, the bellwether, which never goes first but always follows an outlier, is the one that signals to the others that it is safe to go that way. When it moves, the others will also move. Tendency to be outliers or to be bellwethers, or stick in the middle of the flock, seems to stay with a sheep its whole life. There might be genes that make them repeat this role behaviour.

Probably the most famous sheep was Dolly the Sheep. She was named after Dolly Parton, and was the first large mammal clone. She did not live as long as a regular sheep, because clones have health problems. This is only known because of Dolly. She had sisters from the same DNA, but they did not look the same. This proved that environment has more to do with the way a sheep looks than heredity. This too is known only because of Dolly and her sisters. Dolly advanced science and scientists are very grateful to her.

Fat-tailed sheep[edit]

These sheep are so named because they can store large amounts of fat in the tail and the region of the rump. They are kept mainly because they make more milk than other types of sheep; but their wool is coarse and long, and is mostly used for making carpets. Fat-tailed sheep are found mainly in the very dry parts of Africa, the Middle East, and Asia, and they represent about 25 percent of the sheep in the world. The major breeds are the Awassi, Bakhtiari, Karakul, Ghashghai, and Kermani.