The 5 kingdoms of nature

Nature is made up of a great diversity of living beings, among which we humans are. Inside of her, we can differentiate up to 5 kingdoms of nature: the animal, vegetable, fungi, protist and monera or prokaryote.

Each kingdom shares a number of common characteristics. In this article we will see what are the parameters that allow this classification, and what are the defining characteristics of each group. In addition, we mention examples from each kingdom.

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The five kingdoms of nature and their characteristics

In the world of nature, there are 5 well differentiated kingdoms. The criterion that classified these kingdoms of nature was proposed, in 1977, by the microbiologist Carl Woese. Currently, this classification is the most agreed among many scientists who are experts in the taxonomy of living beings., and is based on other criteria.

The kingdoms of nature are:

• The animal kingdom
• The plant kingdom (plantae)
• The fungi kingdom
• The protist kingdom
• The monera kingdom

Shared features

The kingdoms of nature mentioned share a series of characteristics (which differ in each of the kingdoms), and they are the following.

1. Cell organization

This can be of two types: unicellular (a single cell) or multicellular (millions of cells). Examples of unicellular organisms are bacteria, some algae and fungi, protozoa... And examples of multicellular organisms are: humans, mammals ...

2. Cell type

The organism cell can be, as in the previous case, of two types: eukaryotic or prokaryotic. Eukaryotic cells (typical of humans, for example) are those that have their hereditary material (DNA) enclosed within a double membrane.

Eukaryotic cells are much more complex than prokaryotic cells, which, in this case and unlike the previous ones, do not have a nucleus, and their DNA is located in the cytoplasm.

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3. Playback type

Reproduction can be of three types: sexual, asexual or spore reproduction.

4. Nutrition

Nutrition can also be of two types: heterotrophic or autotrophic. The first implies that organic matter is transformed into nutrients, and energy, and that the animal obtains it from there. The second implies that the organism generates its own food, such as plants and some bacteria).

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5. Locomotion

Living beings can move autonomously (autonomous locomotion) or not move (immobile locomotion).

6. Breathing type

Another characteristic that the kingdoms of nature share is their type of breathing, which can be aerobic or anaerobic.

7. Other features

Finally, each of the five kingdoms has its own (unique) and differentiated characteristics.

What are the organisms of each kingdom like?

Let's get to know the characteristics (and examples) of each of the kingdoms of nature.

1. animal Kingdom

What makes up the animal kingdom? Living organisms that have the following characteristics: they are multicellular, heterotrophic organisms, with respiration aerobic, with eukaryotic cells, which reproduce sexually (in most cases) and move in a autonomous.

In turn, this kingdom is divided into two groups: vertebrate organisms (with backbone or vertebral column) and invertebrate organisms (without spinal column or articulated internal skeleton). The former are subdivided into: fish, reptiles, mammals, birds and amphibians; the latter, for their part, include: insects, worms and mollusks.

Some examples from the animal kingdom are: cows, tigers, lions, humans, bees, elephants, crocodiles, ostriches, penguins... In addition, some animals are microscopic, such as tardigrades.

• You may be interested: "Kingdom Animalia: characteristics, classification and examples"

2. vegetal kingdom

The second of the kingdoms of nature, the plant kingdom (also called kingdom plantae), is made up of organisms that have the following characteristics: multicellular, autotrophic, eukaryotic, immobile, anaerobic and that can reproduce in two ways; sexually or asexually.

The fact that they are autotrophic means that plants generate their own food, thanks to the process of photosynthesis. In fact, they are the only ones that do so, along with certain unicellular algae, belonging to the protist kingdom.

Examples of the plant kingdom are all types of plants (with or without flowers): the magnolia, the tulip, the snow watermelon, the banana plant, the cembra pine, the royal fern ...

3. Fungi kingdom

The fungi kingdom is the kingdom of fungi. In this case, it is made up of organisms with the following characteristics: multicellular, aerobic, immobile, heterotrophic, with eukaryotic cell and that reproduce in three ways: by spores, sexually or asexually.

As a curious fact, this kingdom was included as one of the five kingdoms of nature in 1969, thanks to the classification of the American ecologist Robert H. Whittaker (1920-1980). Specifically, Whittaker established the classification criteria according to the type of cell (prokaryotic or eukaryotic) and the level of cellular organization (unicellular or multicellular). This was achieved through the electric microscope.

But Whittaker went further, and suggested including other classification criteria, already mentioned above. length of the article: the type of nutrition (autotrophic or heterotrophic) and the type of reproduction (sexual or asexual). Some examples of the fungi kingdom are: the star mushroom, the fly swatter, the devil's cigar, the brewer's yeast, the amethyst lacaria ...

4. Protist kingdom

The protist kingdom is characterized by grouping organisms that, due to their characteristics, cannot be included in any other realm. Thus, in a certain way it is a “mixed bag”, because it includes both unicellular and multicellular organisms, autotrophs and heterotrophs, with sexual and asexual reproduction, etc.

Within the prokaryotic kingdom we find protozoa (or protozoa) and algae. Historically, this constitutes the kingdom of "the first eukaryotic forms of life", and it has been considered as such since 1866, when the German naturalist Erndt Haeckel (1834-1919) included it in the classification of the five kingdoms of the nature. However, in his initial proposal, Haeckel included all single-celled organisms in the protist kingdom.

Examples of the protist kingdom (and that you have probably heard little) are: amoeba, gregarine, paramecium, volvox, coanozoa, stentor, cercomonas ...

5. Monera kingdom

Finally, the last of the kingdoms of nature is the brunette kingdom, also called the prokaryotic kingdom. Within this realm we find all unicellular and prokaryotic organisms; thus, they are microscopic beings. They are the only organisms with cells without a defined nucleus. Its genetic material is the simplest of all kingdoms.

These organisms were defined, for the first time, by Ernst Haeckel, in 1866. Later, the biologist Herbert Copeland (1902-1968) also included bacteria in this group. Some examples of the monera kingdom are: Chlamydia bacteria, Escherichia coli bacteria, Lactobacillus casei, Clostridium botulinum, Sorangium cellulosum, Bifidobacteria, Serpulina ...

Bibliographic references:

• Campbell N. and Reece J. (2007). Biology. Editorial Panamericana.
• Raven P.H.; Evert R.F. & S.E. Eichhorn. (1991). Plant Biology, 2 vols. Ed. Reverté, S.A.