Cladistics (from Greek , "klados", i.e., "branch") is an approach to biological classification in which organisms are categorized based on shared derived characteristics that can be traced to a group's most recent common ancestor and are not present in more distant ancestors. Therefore, members of a group are assumed to share a common history and are considered to be closely related. 

The techniques and nomenclature of cladistics have been applied to other disciplines. (See phylogenetic nomenclature.) 

The original methods used in cladistic analysis and the school of taxonomy derived from the work of the German entomologist Willi Hennig, who referred to it as phylogenetic systematics (also the title of his 1966 book); the terms "cladistics" and "clade" were popularized by other researchers. Cladistics in the original sense refers to a particular set of methods used in phylogenetic analysis, although it is now sometimes used to refer to the whole field. 

What is now called the cladistic method appeared as early as 1901 with a work by Peter Chalmers Mitchell for birds and subsequently by Robert John Tillyard (for insects) in 1921, and W. Zimmermann (for plants) in 1943. The term "clade" was introduced in 1958 by Julian Huxley after having been coined by Lucien Cuénot in 1940, "cladogenesis" in 1958, "cladistic" by Cain and Harrison in 1960, "cladist" (for an adherent of Hennig's school) by Mayr in 1965, and "cladistics" in 1966. Hennig referred to his own approach as "phylogenetic systematics". From the time of his original formulation until the end of the 1970s, cladistics competed as an analytical and philosophical approach to phylogenetic inference with phenetics and so-called evolutionary taxonomy. Phenetics was championed at this time by the numerical taxonomists Peter Sneath and Robert Sokal and the evolutionary taxonomist Ernst Mayr. QUESTIONS:

Q1:
1. What is the article about?
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1. What country is the word Cladistics from?
2. What language is at the base of the term cladistics?
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Q3:
1. What is cladistics?
2. How can cladistics be defined?
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1. How long ago did Cladistics come about?
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1. Who invented the cladistic method?
2. Who was one of the first to come out with the cladistic method?
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Q6:
1. How did Peter Chalmers Mitchell first introduce cladistics?
2. What work by Peter Chalmers Mitchell did cladistics first appear in?
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1. Did cladistics appear in the work of people other than Peter Chalmers Mitchell?
2. Did anybody besides Peter Chalmers Mitchell write about cladistics?
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1. Who was the next person to write about cladistics after Peter Chalmers Mitchell?
2. Who followed Peter Chalmers Mitchell in writing on cladistics?
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1. How many years separated Peter Chalmers Mitchell's work on cladistics and that of Robert John Tillyard?
2. How many years after Peter Chalmers Mitchell did Robert John Tillyard write about Cladistics?
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1. What was the focus of Robert John Tillyard's work?
2. What did Roberty John Tillyard mostly work on?
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1. Who was the next person to write about cladistics after Robert John Tillyard?
2. Who followed Robert John Tillyard in writing on cladistics?
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1. What was the focus of W. Zimmerman's work?
2. What did W. Zimmerman mostly work on?
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1. When was W. Zimmerman active?
2. In what year did W. Zimmerman publish?
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1. How are organisms classified under cladistics?
2. What classification does cladistics give of organisms?
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Q15:
1. Who came up with "clade"?
2. Who was the first to use the term "clade"?
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