Transitional fossils are the fossilized remains of intermediary forms of life that illustrate an evolutionary transition. They can be identified by their retention of certain primitive traits in comparison with their more derived relatives. Numerous examples exist, including those of primates and early humans.
A popular term used to designate transitional forms is ‘missing links.’ The term tends to be used in the popular media, but is avoided in the scientific press as it relates to the links in a linear chain of being, a pre-evolutionary concept now abandoned, and replaced with a taxonomic family tree with many branches and dead ends. However, the idea of a ‘missing link’ between humans and so-called ‘lower’ animals remains lodged in the public imagination. The concept was fueled by the discovery of Australopithecus africanus (Taung Child), Java Man, Homo erectus, Sinanthropus pekinensis (Peking Man) and other Hominina fossils.
All populations of organisms are in transition. Therefore, a ‘transitional form’ is a human construct of a selected form that vividly represents a particular evolutionary stage, as recognized in hindsight. Contemporary ‘transitional’ forms are referred to as ‘living fossils.’ Not every transitional form appears in the fossil record because the fossil record is nowhere near complete. Organisms are only rarely preserved as fossils in the best of circumstances and only a fraction of such fossils have ever been discovered. Furthermore the fossil record is very uneven. Certain kinds of organisms, for example those without hard body parts like jellyfish and worms, are very poorly represented.
The Daily Omnivore 
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