swarm
A herd is a group of animals gathered together. Many animals live together. Since every animal is an individual life and a community life, each individual gathering is the nature of the animal. In addition, there is a passive gathering by the outside environment, and there is also gathering under a favorable environment. It is well known that African elephants, zebras, and nutrients form flocks in African grasslands. In Asia and Europe, the reindeer of the north is living in the southern grassland. In North America, the bison living in the northern calibes and the southern grasslands live together. Bison was alive with a large group of people earlier in the 19th century, and was killed by humans in the early 19th century. However, it has been protected and is now living in a protected area. This group of high animals move and nomadic life in a certain area is called 'herd'.