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Jaina Biology
basis of their anatomy, physiology and biochemisty, their embryologic and genetic histories, ete.
The fact that the characteristics of living things - size and shape, metabolism, movement, irritability, growth, reproduction and adaptation, as discussed in the second section of the first chapter, are such that they can be fitted into a hierarchical scheme of categories - species, genera, etc.9 - can best be interpreted as indicating evolutionary relationship. The evidence from Anatomy :
Homologous organs ; Comparisons of the structure of group of animals and plants as described in Jaina Biology reveal that each organ system has a certain basically similar pattern that is varied to some extent among the members of a given phylum. The skeletal, circulatory and excretory systems of vertebrates ( pancendriyajıvas )10 provide particular clear illustration of this. "Only similarities based on homologous organs are valid in attributing evolutionary relationship". 11 Homologous organs are basically similar in structure, in their relationships to adjacent structures, in their embryonic development and in their nerve and blood supply.12 For example, a bat's ( valguli )13 wing, a cat's (mārjāra)14 paw, a horse's ( aśva )15, front leg and the human (manuşya)16 hand and arm, (päni) 16/a though superficially dissimilar and adapted for quite different functions, are homologous organs.
According to modern Biology, "each consist of almost the same number of bones, muscles, nerves and blood vessels, arranged in the same pattern and with very similar modes of development."17
A study of the evidence of the existence of such homologus organs indicates a common evolutionary origin of these
fifth, first and fourth
9. Sec Second Chapter and Third Chapter. 10. See the fourth chapter - organisation of the body, its
sections respectively. 11. Biology, p. 544. 12. Ibid. 13. Tattvarthadhigama Sutra II 34. 14. Ibid. 15. Ibid. 16. Tattvärthadhigama Sutra II. 34. 16/a Tandula Veyaliya 2, 17. Biology, p. 544.
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