Palaeos		The Great Chain of Being
Systematics		The Great Chain of Being

The human pedigree interpreted chain of being with living and fossil animals. Ernst Haeckel, Anthropogenie oder Entwicklungsgeschichte des Menschen (The Evolution of Man), 1874, posted by Petter Bøckman, Wikipedia, Public Domain. The figure show the human pedigree as a Great Chain of Being, illustrated by modern and fossil species. Legend: 1 Amoeba, 1a Asexual reproduction (amoeba dividing), 2 Sexual reproduction (cell with spore), 3 Multi-cellular organism (early embryonic stage), 4 Muliticellular organism with three germ layers (blastula), 5 Organism with primitive mouth (gastrula), 6 Planaria, 7 Worm (leech), 8 Primitive chordate (tunicate larva), 8a Adult tunicate, 9 Lancelet, 10 Jawless fish (lamprey), 11 Cartilaginous fishes (shark), 12 Australian lungfish, 13 South American lungfish, 14 Aquatic reptile (plesiosaur), 15 Early amphibian (labytinthodont), 16 Modern amphibian (newt), 17 Reptile (iguana), 18 Monotreme (platypus), 19 Marsupial (kangaroo), 20 Prosimian (lemur), 21 Monkey (langur), 22 Ape (orangutan), 23 Ape-man (Pithecanthropus), 24 Modern human (a Papuan).

Today we think of life as organised in terms of an evolutionary tree. Little more than one and a half centuries ago this idea was unheard of. Instead there was the Great chain of being. This evocative phrase was coined by historian of ideas Arthur O. Lovejoy in his study, called, what else, The Great Chain of Being. The premise was developed by Greek philosophers such as Plato (transcendent ideas), Aristotle (scala naturae or Ladder of Nature), and Plotinus. In the Middle Ages this cosmology was the basis for both scholastic theology (ranking all of creation from dirt through to humans to angels) and feudal social stratification; it formed a central element in the Elizabethan understanding of the world still evident in Shakespeare's plays. It continued through 17th, 18th and early 19th century Europe and North America, in an understanding of the universe as the highest good, in which every species of being has its perfect place. The end of the 18th century saw the "temporalization of the great chain of being" with a timeless metaphysical ladder being replaced by a dynamic ascending one. This continues in some contemporary pop cultural approaches such as the "Ascent of Man" (in this context see also the diagram by Haeckel, above). Hard science themes such as complexity theory and emergent evolution, although unrelated, can be considered a modern parallel of this. MAK111018 130319