Order (biology)

Order is one of the eight main groups used by scientists to sort and study living things. It sits between two other groups called family and class. All living things in the same order share a common ancestor. For example, all owls belong to the order Strigiformes.

Scientists called taxonomists decide which living things belong to each order and whether an order should even be used. They don't always agree, so sometimes different scientists might put living things in different orders.

Orders often have special naming patterns. For plants, fungi, and algae, orders usually end in "-ales". Birds and fishes often have names ending in "-iformes", meaning "having the form of". Many insects have orders ending in "-ptera", meaning "wing". But mammals, reptiles, amphibians, and invertebrates don't follow such a clear pattern.

Hierarchy of ranks

In biology, scientists group living things into different levels or "ranks" to show how they are related. One of these ranks is called "order," which sits between two other ranks: family and class. For example, all owls belong to the same order, which helps us understand they share common traits.

In studying animals, some scientists have added extra levels between bigger groups, but these aren't always officially recognized. In plants, there are also special ranks that fit above and below the order rank, helping to organize the many different types of plants.

History

The idea of an "order" in biology started with a German botanist named Augustus Quirinus Rivinus in the 1690s. Later, Carl Linnaeus used this idea in his famous book, Systema Naturae, in 1735. He applied it to minerals, plants, and animals to help organize them into groups.

In plants, Linnaeus used orders to break bigger groups into smaller, easier-to-understand parts. Over time, scientists changed how they used these orders. In animal studies, Linnaeus's orders were more stable and some names, like Lepidoptera for moths and butterflies, are still used today.

For viruses, orders were once the highest grouping until 2018 when new higher groups were added. Virus orders end in "virales".