(The). According to Darwin, the higher animals are developed from the lower ones. The lowest form of animal life is protoplasm, which develops into amoebae (cell life), and thence, successively, into synamoeacute;bæ, gastrula, hydra, medusa, worms, hematega, ascidians, fish, amphibians, birds and reptiles, monotremata, marsupials, placental mammals, &lemuridae;, monkeys [missing link], man.
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894
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