Animal

From ArticleWorld


The term, animals is used to refer to a major group of organisms that are classified in the kingdom, Animalia. This category will touch upon a variety of animals, their study, as well as their classification. Human beings are also classified as being a member of the animal kingdom. The name animal comes from the Latin word animal. Animalia is the plural form which comes from anima, which means soul or vital breath.


Contents

Usage of the word animal


Everyday language uses the word, animal to describe any member of the animal kingdom. Humans are not included in this usage, creating two separate phrases humans and animals.


Kingdom Animalia characteristics


The kingdom, Animalia presents several characteristics that separate it from other living creatures such as:

Animals are eukaryotic, meaning that these organisms possess complex cells, where their genetic material is contained within a distinct membrane-bound nucleus.

Animals are multicellular, which makes them separate from Kingdom Protista (algae and slime moulds).

Animals are heterotrophic, which sets them apart from Kingdom Plantae, as well as several plant-like protists. A heterotroph must obtain its carbon from organic compounds. This means that animals are unable to make their own food and must feed on other organisms in order to get the necessary nutrition to survive. Plants are able to make their own food through the process of photosynthesis.

Organisms within the Kingdom Animalia do not possess cell walls. Cell walls are found in Kingdom Plantae, algae and Kingdom Fungi.


Classification History


The first people to classify the living world and divide the organisms between plants and animals, was Aristotle. His work was followed by Carolus Linnaeus, who developed the first hierarchical classification. Originally, Linnaeus stated that animals were one of three kingdoms, which were then divided into classes called Vermes, Insecta, Pisces, Amphibia, Aves and Mammalia. Since then, the last four were grouped into a single phylum referred to as the Chordata.


Animal Categories


Some of the animals covered in this category include:


Insect includes Ant, Bee, Beetle, Butterfly, Cockroach, Earthworm


Bird includes Owl, Chicken, Swan, Duck, Parrot, Peacock


Mammal includes Cat, Dog, Cow, Horse, Bear, Dolphin, Gorilla, Lion


Amphibian and Reptile includes Frog, Toad, Snake, Iguana, Turtle


See Also:


Biology

Fish

Zoology

Zoo