Animal Kingdom
Classifying Animals:
Amidst all the marvelous diversity of life on Earth—between 10 and 30 million distinct species are thought to populate the planet—it's not surprising that some living things have similar body parts and structures, while others have nothing in common. To help us better understand the natural relationships that exist between species, scientists called taxonomists attempt to place organisms in distinct groups through careful examination of their characteristics.
For hundreds of years, philosophers and naturalists sought ways to classify the various living things that populate the planet. Until recently, they focused solely on physical characteristics, such as body part size and bone structure.
Today, taxonomists use genetics to further assist them in classifying organisms. They compare DNA sequences to determine evolutionary relationships between specimens they study. The millions of chemical letters of DNA code stored in the cells of all living things provide a distinctive genetic profile of a species. The more similar sequences there are between species, the closer their evolutionary relationship.
The ability to place plants or animals in groups allows scientists to apply new information about one living thing to other, related ones. Furthermore, we can use existing information about a plant or animal to improve its care, monitor its health, and, in the case of threatened or endangered species, help in establishing recovery programs.
For hundreds of years, philosophers and naturalists sought ways to classify the various living things that populate the planet. Until recently, they focused solely on physical characteristics, such as body part size and bone structure.
Today, taxonomists use genetics to further assist them in classifying organisms. They compare DNA sequences to determine evolutionary relationships between specimens they study. The millions of chemical letters of DNA code stored in the cells of all living things provide a distinctive genetic profile of a species. The more similar sequences there are between species, the closer their evolutionary relationship.
The ability to place plants or animals in groups allows scientists to apply new information about one living thing to other, related ones. Furthermore, we can use existing information about a plant or animal to improve its care, monitor its health, and, in the case of threatened or endangered species, help in establishing recovery programs.
- Why do we classify animals in different categories?
- What is the difference between an amphibian and a reptile?
- Is there any type of animal that is common to both ecosystems?
- What is the basic body plan of an insect?
- If you encountered a smallish creature, what structures would you look for to decide if it was an insect or not?
- What structures do mammals, birds, amphibians, and reptiles have in common?