Cladistics is a method which helps scientists figure out how an organism is related to another through evolution. Scientists will use this method to create new tables for how and why evolution happens, as well as creating a table for all organisms and their relation to each other. These are usually listed as characteristics; which cladistics helps figure out. Think of it like statistics, but for evolution.

The need for classifications goes back to the 1700s. Charles Darwin had not come out with his theory of evolution, so evolution wasn't a topic back then. Instead, biologists needed classifications to better identify animals in certain regions, why the were there, and how they were different from species to species.

Even though two organisms can have similar or the same characteristics, it does not mean they're related directly. A common example would be, which are closer related to another, a starfish, a jellyfish or a human. Though people may think the jellyfish and the starfish are more related because they live in water. This is not accurate however, because humans evolved from fish, which makes us more closely related than a jellyfish, which comes from a completely different stem of evolution.

Cladists are the scientists behind making sure cladistics keeps going. They must make assumptions about cladistics, which allows for unity in the information gathered. They are needed by biologists so that they can have easy to read systems of classification.

The first assumption they must make is that life was only made once, and that all living organisms are related to them. This means that all life comes from a single reproducing organism.

The second assumption is that new organisms can be formed when a species divides into exactly two groups, though this is often the most controversial one. Some scientists contest that while there are many lineages (family), some species don't need to be categorized as a new organism. Another objection is that interbreeding can cause mutations in the DNA which cause the appearance of a new species but are still related to the same.

The last assumption is that characteristics of organisms can change over time. This is the entire basis of cladistics, and recognizes the different characteristics of each lineage. The original characteristics of an organism are called pleiomorphic (primitive) and the altered or changed form is called apomorphic (derived).

Cladistics has existed for hundreds of years, long before Darwin's theory of evolution. The advances it made up until that point were remarkable, and the fact it managed to couple with evolution so well make an even stronger case. As we learn about new organisms, species, and their sub-sections, we will be able to paint a better picture of the origins of life.

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