The segregation may be geographical, or may be the result of preferential mating, or of seasonal mating, and its effects plainly can be made no more of than proximate or empirical laws of differentiation, of great importance in codifying and simplifying the facts to be explained.
The minute attention paid by modern systematists to the exact localities of subspecies and races is bringing together a vast store of facts which will throw further light on the problem of segregation, but the difficulty of utilizing these facts is increased by an unfortunate tendency to make locality itself one of the diagnostic characters.
It is possible, however, that the segregation of characters in the gametes may depend upon something far more subtle and elusive than the chromosomes or even of possible combinations of units within the chromosomes, but so far as we can see at present these are the only structures in the cell with which it can be satisfactorily associated.
A curd soap prepared from kitchen fat or bone grease always carries with it into the cooling frame a considerable amount of coloured impurity, such as iron sulphate, &c. When it is permitted to cool rapidly the colouring matter remains uniformly disseminated throughout the mass; but when means are taken to cause the soap to cool and solidify slowly a segregation takes place: the stearate and palmitate form a semi-crystalline solid, while the oleate, solidifying more slowly, comes by itself into translucent veins, in which the greater part of the coloured matter is drawn.
The suggestion is obvious that the halving of the number of nuclear threads in the reproductive cells as compared with the number of those present in the ordinary cells of the tissues - a phenomenon which has now been demonstrated as universal - may be directly connected with the facts of segregation of hybrid characters observed by Mendel.
But licensing is associated with strict segregation, and it results that the great cities are conspicuously free from evidences of vice, and that the streets may be traversed by wonien at all hours of the day and night with perfect impunity and without fear of encountering offensive spectacles.
He also assumes that" Evolution "is a real, nay, an ultimate law of nature, but his evidence only goes to show that it is a result, in some cases, of the complex interaction of laws, which, like Rhythm, Segregation, &c., are in their turn only tendencies, and may be, and often are, counteracted.
Several important attempts have been made to effect a segregation as between state and local taxes, but for the most part without success.
On a smaller scale are the local adaptive radiations which occur through segregation of habit and local isolation in the same general geographic region wherever physiographic and climatic differences are sufficient to produce local differences in food supply or other local factors of change.
This local divergence may proceed as rapidly as through wide geographical segregation or isolation.
Cuenot and Hurst have also shown that when albinoes of one colour extraction are crossed with albinoes of another colour extraction the segregation of the colour determinants in the gametogenesis of the albinoes takes place in precisely the same way that it does in the gametogenesis of a pigmented individual; that is, in Mendelian fashion.
While segregation injures the metal here, often fatally, by giving it an indeterminate excess of phosphorus and sulphur, it clearly purifies the remainder of the ingot, and on this account it ought, under certain conditions, to be promoted rather than restrained.
The following is an extreme case: - The surprising fact that the degree of segregation does not increase greatly either with the slowness of solidification or with the size of the ingot, at least between the limits of 5 in.
According to their view, in the formation of the germ cells a segregation of the unit pairs occurs - that is to say, the peculiar body or ferment is handed on to one daughter-cell but not to the other.
A similar kind of segregation may take place in the formation of the repeated parts of an organism, so that symmetrical repetition may be compared with normal heredity, and be due to the presence of similar factors in the divisions of the embryonic cells, whilst the differentiation of repeated parts may be due to the unequal distribution of such factors and be comparable with variation.
It emphasized the excellence of the system devised in 1879 for the segregation of the comparatively innocent from convicts hardened in crime.
Amongst these fragments were the seeds of all things which have since emerged by the process of aggregation and segregation, wherein homogeneous fragments came together.
It is in the aggregation and segregation of elements thus arising that Empedocles, like the atomists, finds the real process which corresponds to what is popularly termed growth, increase or decrease.