Heredity Quotes (17)
A moment's consideration of this case shows what a really great advance in the theory and practise of breeding has been obtained through the discovery of Mendel's law. What a puzzle this case would have presented to the biologist ten years ago! Agouti crossed with chocolate gives in the second filial generation (not in the first) four varieties, viz., agouti, chocolate, black and cinnamon. We could only have shaken our heads and looked wise (or skeptical).
Then we had no explanation to offer for such occurrences other than the 'instability of color characters under domestication,' the 'effects of inbreeding,' 'maternal impressions.' Serious consideration would have been given to the proximity of cages containing both black and cinnamon-agouti mice.
Now we have a simple, rational explanation, which anyone can put to the test. We are able to predict the production of new varieties, and to produce them.
We must not, of course, in our exuberance, conclude that the powers of the hybridizer know no limits. The result under consideration consists, after all, only in the making of new combinations of unit characters, but it is much to know that these units exist and that all conceivable combinations of them are ordinarily capable of production. This valuable knowledge we owe to the discoverer and to the rediscoverers of Mendel's law.
Then we had no explanation to offer for such occurrences other than the 'instability of color characters under domestication,' the 'effects of inbreeding,' 'maternal impressions.' Serious consideration would have been given to the proximity of cages containing both black and cinnamon-agouti mice.
Now we have a simple, rational explanation, which anyone can put to the test. We are able to predict the production of new varieties, and to produce them.
We must not, of course, in our exuberance, conclude that the powers of the hybridizer know no limits. The result under consideration consists, after all, only in the making of new combinations of unit characters, but it is much to know that these units exist and that all conceivable combinations of them are ordinarily capable of production. This valuable knowledge we owe to the discoverer and to the rediscoverers of Mendel's law.
'New Colour Variety of the Guinea Pig', Science, 1908, 28, 250-252.
See also: | Mouse (2)
Characteristics cling to families.
Hereditary Genius (1869), v.
For it is not cell nuclei, not even individual chromosomes, but certain parts of certain chromosomes from certain cells that must be isolated and collected in enormous quantities for analysis; that would be the precondition for placing the chemist in such a position as would allow him to analyse [the hereditary material] more minutely than [can] the morphologists ... For the morphology of the nucleus has reference at the very least to the gearing of the clock, but at best the chemistry of the nucleus refers only to the metal from which the gears are formed.
Ergebnisse über die Konstitution der chromatischen Substam des Zellkems (1904), 123. Translated in Robert Olby, The Path to the Double Helix: The Discovery of DNA (1994), xx.
Heredity is to-day the central problem of biology. This problem may be approached from many sides—that of the breeder, the experimenter, the statistician, the physiologist, the embryologist, the cytologist—but the mechanism of heredity can be studied best by the investigation of the germ cells and their development.
'The Mechanism of Heredity', Science, 1905, 27, 89-90.
See also: | Cell (20)
Heredity, to our understanding is not capable of giving to this illness (paraphilia) its characteristic form ... Heredity invents nothing, creates nothing anew; it has no imagination.
Études de psychologie expérimentale: Le fétichisme dans l’amour (1888), 42.
I am the family face:
Flesh perishes, I live on,
Projecting trait and trace
Through time to times anon,
And leaping from place to place
Over oblivion.
Flesh perishes, I live on,
Projecting trait and trace
Through time to times anon,
And leaping from place to place
Over oblivion.
'Heredity'. In James Gibson (ed.), The Complete Poems of Thomas Hardy (1976), 434.
If we thus go very far back to the source of the Mammalian type of organisation; it is extremely improbable that any of [his relatives shall likewise] the successors of his relations now exist,—In same manner, if we take [a man from] any large family of 12 brothers & sisters [in a state which does not increase] it will be chances against anyone [of them] having progeny living ten thousand years hence; because at present day many are relatives so that tracing back the [descen] fathers would be reduced to small percentage.—& [in] therefore the chances are excessively great against, any two of the 12, having progeny, after that distant period.
P. H. Barrett et al. (eds.), Charles Darwin's Notebooks, 1836-1844: Geology, Transmutation of the Species and Metaphysical Enquiries (1987), Notebook B, 40-1.
In the course of individual development, inherited characters appear, in general, earlier than adaptive ones, and the earlier a certain character appears in ontogeny, the further back must lie in time when it was acquired by its ancestors.
Allgemeine Entwickelungsgeschichte der Organismen (1866), Vol. 2, 298. Trans. Stephen Jay Gould, Ontogeny and Phylogeny (1977), 81.
See also: | Genetics (39)
It is clear that in maize, seemingly blending is really segregating inheritance, but with entire absence of dominance, and it seems probably that the same will be found to be true among rabbits and other mammals; failure to observe it hitherto is probably due to the fact that the factors concerned are numerous. For the greater the number of factors concerned, the more nearly will the result obtained approximate a complete and permanent blend. As the number of factors approaches infinity, the result will become identical with a permanent blend.
Heredity: In Relation to Evolution and Animal Breeding (1911), 138-9.
Ontogeny is a short and quick repetition, or recapitulation, of Phylogeny, determined by the laws of Inheritance and Adaptation.
The History of Creation (1876), Vol. 2, 33.
Owing to the imperfection of language the offspring is termed a new animal, but it is in truth a branch or elongation of the parent; since a part of the embryon-animal is, or was, a part of the parent; and therefore in strict language it cannot be said to be entirely new at the time of its production; and therefore it may retain some of the habits of the parent-system. (1794)
Zoonomia, Or, The Laws of Organic Life, in three parts (1803), Vol. 1, 395.
The admirable perfection of the adaptations of organisms and of their parts to the functions they perform has detracted attention from the fact that adaptedness does not consist of perfect fit, but capacity to fit or to adapt in a variety of ways: only in this sense is adaptedness a guarantee of further survival and evolutionary progress, for too perfect a fit is fatal to the species if not to the individual. This, I think, sets phylogeny and ontogeny in the correct perspective. It is the genotype which bears the marks of past experience of the species and defines the range of possible fits. What fit is actually chosen, what phenotype is actually evolved, is determined by the ever renewed individual history.
'The Interplay of Heredity and Environment in the Synthesis of Respiratory Enzymes in Yeast', The Harvey Lectures: Delivered under the auspices of The Harvey Society of New York 1950-1951, 1951, 156, 45-6.
The genes are the atoms of heredity.
'Genetic Fine Structure', Lecture delivered 15 September 1960. Quoted in The Harvey Lectures, Series 56 (1961), 1.
See also: | Gene (13)
The ovary of an ancestress will contain not only her daughter, but also her granddaughter, her great-grand-daughter, and her great-great-granddaughter, and if it is once proved that an ovary can contain many generations, there is no absurdity in saying that it contains them all.
Attributed.
The philosophical implication of race-thinking is that by offering us the mystery of heredity as an explanation, it diverts our attention from the social and intellectual factors that make up personality.
Race(1937), 282.
The processes concerned in simple descent are those of Family Variability and Reversion. It is well to define these words clearly. By family variability is meant the departure of the children of the same or similarly descended families from the ideal mean type of all of them. Reversion is the tendency of that ideal mean type to depart from the parent type, 'reverting' towards what may be roughly and perhaps fairly described as the average ancestral type. If family variability had been the only process in simple descent, the dispersion of the race would indefinitely increase with the number of the generations, but reversion checks this increase, and brings it to a standstill.
Typical Laws of Heredity (1877), 513.
We shall therefore take an appropriately correct view of the origin of our life, if we consider our own embryos to have sprung immediately from those embryos whence our parents were developed, and these from the embryos of their parents, and so on for ever. We should in this way look on the nature of mankind, and perhaps on that of the whole animated creation, as one Continuous System, ever pushing out new branches in all directions, that variously interlace, and that bud into separate lives at every point of interlacement.
'Hereditary Talent and Character', Macmillan's Magazine, 1865, 12, 322.
See also: | Embryo (7)
Sitewide search within all Today In Science History pages:
Names index: | A
| B
| C
| D
| E
| F
| G
| H
| I
| J
| K
| L
| M
| N
| O
| P
| Q
| R
| S
| T
| U
| V
| W
| X
| Y
| Z |
Categories index: | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
Categories index: | A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z |
