Heredity is the transmission from parent to offspring of physical and intellectual characters. This has been at all times believed in, but it was only in Victorian times that the conviction was, for the first time, in the hands of Darwin, Herbert Spencer, and Wallace, been methodized so as to embody an important zoological doctrine. The Victorian view of evolution in biology rested upon the belief that acquired peculiarities, or differences which may arise between parent and offspring, could be transmitted with some probability of permanence, especially if the variation presented by the young was determined by external conditions, or if it was such as to adapt the possessor more thoroughly to the conditions under which it is placed. On the other hand, while variations may be thus permanently transmitted by heredity, yet this very tendency of the young to repeat the characters of the parent is also a check on variability, or the tendency of structure and attributes to change with the environment. It may be noted that while the strong tendency to hereditary transmission works in the majority of cases so as to perpetuate those most fitted to survive, it secures the same result in other cases by a converse action. The descent of disease in families tends ultimately to purify the race by accumulating incapacities which end in the extinction of the enfeebled strain. The discovery of genetics in the 20th century built upon the earlier theories of heredity, and explained, to a degree, the transport of the passing on of the characteristics. Research Heredity
Kinship is human relations based on biological descent and marriage. Kinship is founded on social differences and cultural creations. In all societies, the links between blood relatives and relatives by marriage are assigned certain legal, political, and economic significance that does not depend on biology. At the basis of kinship is the primary mother-child bond to which diverse cultures have added different familial relations. Additional kin are recruited to this basic unit by the principle of descent, which connects one generation to the other in a systematic way and which determines certain rights and obligations across generations. Descent groups can be traced through both sexes (that is, ambilaterally) or through only the male or the female link (unilaterally). In unilaterally traced groups the descent is known as patrilineal if the connection is through the male line or matrilineal if it is through the female line.
Less frequent forms for tracing descent are the parallel system, in which males and females each trace their ancestry through their own sex; and the cognatic method, in which the relatives of both sexes are considered, with little formal distinction between them. The study of kinship has directed much attention to the terms people use to classify and identify their relatives. Kin are everywhere categorised into distinct groups with specific roles and behaviour. The way in which people classify their kin has many practical applications. Thus, the familial relationships peculiar to a society will largely determine the allocation of rights and their transmission from one generation to the next. The succession of office and titles and the inheritance of property are implicit in the kinship system. Property can pass across generations in several ways, as, for example, from the mother's brother to the sister's son (in matrilineal societies); from the father to the father's younger brother (in some patrilineal cultures); or from the father to his son (in many patrilineal societies).
In some societies, kinship terms may also indicate how the family is split over the inheritance of goods and property. The Iatmul of New Guinea, for instance, assign five different terms to designate the first, second, third, fourth, and fifth child. In any quarrels over patrimony, the first and third children are expected to join forces against the second and the fourth. The evolution of kinship and its terminology has interested anthropologists since the mid- 1800s, when the American anthropologist Lewis Henry Morgan developed his theory of kinship. He held that kinship terminology used in non-literate societies reflected a low level of culture and that the terminology common in civilised societies indicated an advanced stage of development. This theory was abandoned when the discovery was made that the limited number of kinship systems in use are found among both technologically simple and advanced peoples.
Some non-evolutionary theories see kinship terms as a result of culture borrowings and modifications, as a means of understanding aspects of the history of a particular society, or even as a linguistic phenomenon. The most common anthropological view, however, is a functional one that relates kinship terms to contemporary behaviour. In this theory, the terms are considered tools for understanding the ties between-and values of- people in any given society. Kinship is important in anthropological study because it is universal. It connotes certain basic human attachments made by all people, and it reflects the way in which people give meaning and ascribe importance to human interactions. Research Kinship
Teleology is the explanation by reference to ends, purposes, or function, as in, 'Why do you have such big teeth, Grandmama?' - 'All the better to eat you with, my dear!' Aristotle considered teleological explanations to be a particularly illuminating kind of causal explanation, and contrasted them with explanations citing efficient causes, the prior state of affairs that brings something about. In Aristotle the value of teleological explanations rests on his metaphysical doctrine of forms, the fundamental kinds into which all things fall, and which define their proper ends. Without some such metaphysical underpinning, the use of such explanations is hard to justify; in particular, the mechanistic world-view characteristic of much of modern science emphasises efficient causation and seems to leave little room for purposefulness. The great achievement of Darwin's theory of evolution was to show how some teleological explanations in biology could be rested on a mechanistic foundation. How far this kind of reconciliation is possible is a live issue in the philosophy of science. Perhaps the most famous teleological argument is that for the existence of God, which takes our observations of the regularity and coherence of the world around us and our experience of the conjunction of regularity and design, to conclude that there must be a designer. Research Teleology
In biology, the term abort describes something that has become checked in its normal development, so as to either remain rudimentary or shrink away wholly. Research Abort
In biology aborted describes something rendered abortive or sterile; undeveloped or checked in its normal development at a very early stage. For example spines are aborted branches. Research Aborted
In biology, atavism is the tendency to reproduce the ancestral type in animals or plants which have become considerably modified by breeding or cultivation; the reversion of a descendant to some peculiarity of a more or less remote ancestor. Research Atavism
In biology, blastoderm is the germinal skin or membrane forming the superficial layer of the impregnated ovum, and from which the rudiment of the new being is formed. Research Blastoderm
Abbreviations
Research Heredity
