In the first place, we may assume in this society, as in the whole of mankind and in the majority of higher animals, a physiological basis for jealousy in the form of an innate instinct;[346] a natural aversion of an individual towards an encroachment on his sexual rights and a natural tendency to expand these rights as far as possible--within certain variable limits. That among the Australian aborigines such instincts of jealousy are not absent, that they are, on the contrary, very strongly developed, is evident from nearly all the facts quoted and all general considerations. It is proved by the high esteem in which in some tribes chastity is held; by the fact that fidelity is required in all other tribes, and that it yields only to custom. The demand for fidelity in all tribes has been discussed above. There is a whole series of statements that emphatically affirm a very strong feeling of jealousy; and connected with it is the fact that the majority of fights and quarrels are about women (Curr, Dawson, Mrs. Parker, Schürmann, Wilhelmi, Wilkes, Turnbull, Phillipps, Tench, Spencer and Gillen). Now, that these instincts of jealousy do not assume the delicate and refined form they possess in our society, results merely from the difference in the corresponding collective ideas which influence and mould the elementary instinct. [346] This expression is perhaps inexact. But this is not the place for psychological and biological analyses. The reader may be referred to Dr. Westermarck's conclusion that there is a strong instinct of sexual jealousy among primitive races of men, both in males (_H.H.M._, pp. 117-132) and in females (_ibid._, pp. 495-500). This instinct is inherited from our animal ancestors (compare Darwin, _Descent of Man_, ii. p. 395). Important for us are the examples of female jealousy, quoted by Westermarck from the Australian material; Narrinyeri, Taplin, p. 11; Palmer, p. 282; Lumholtz, p. 213; Waitz Gerland, pp. 758, 781. With our few data available we can attempt only a sketch of the psychology of the feelings of jealousy among the aborigines. It may be observed that although the sentiment of sexual love might be postulated in all human hearts, it seems to be, to a certain extent, banished from the majority of the Australian matrimonial matches by the very way in which they were brought about.[347] [347] Compare above, p. 83.