The recessive nature of albinism and its distribution in Mendelian fashion is almost certainly as true for man as for lower forms.
We ought from such a cross to obtain equal numbers of dominant and recessive individuals, and further, the dominants so produced ought all to give both dominants and recessives in the ratio 3 : 1 when they themselves are bred from.
The occasional appearance of a sport in a supposedly pure strain is {166} often due to the reappearance of a recessive character.
Again, in some sweet peas the anthers are sterile, setting no pollen, and this condition is recessive to the ordinary fertile condition.
Further, we have seen that the hooded standard is recessive to the ordinary erect standard.
The dominant and recessive white poultry are indistinguishable in appearance.
Though the beard is obviously the additional character, the bearded condition is recessive to the beardless.
The cross between a heterozygous dominant and a recessive also leads to equal numbers of recessives and of heterozygous dominants.
Each of these had been previously shown to behave as a simple recessive to colour.
This was an illustration of the statement that recessives which are supposed to come from two pure recessive gametes show in their soma traces of the dominant type.
Comparing tables 45 to 54, we see that recessive parents are characterized by a low grade of nostril and they, of course, tend to produce offspring with a low grade.
Some are probably matings of two heterozygotes, others of two recessives, and others still of a recessive with a heterozygote.
If a heterozygous bird be mated to a recessive the variability of the offspring is much increased, owing to the occurrence in the progeny of both DR and RR individuals (table 40).
Hence, not infrequently the recessive condition is at first seen and is only later replaced by the dominant condition.
That shortness is recessive is proved by various matings of extracted short × short crest.
If absence of boot is recessive, then, combined with imperfection of dominance, at least 25 per cent of the offspring should be recessive and probably a much larger proportion.
Mendelian expectation in the DR × R cross is 50 per cent of the recessive (4-4) type.
It now remains to test our conclusions by reference to the mating of the heterozygote with the dominant and with the recessive types, respectively.
First of all, it must be confessed that the provisional hypothesis, suggested in my earlier report, that rumplessness is in my strain recessive has not been supported by the newer facts.
In table 31 the two recessive varieties, mated inter se, produce no featherless shanks; the feathers grow freely as they do over the rest of the body.
About the question of recessive kulturverlaengerung.
The same traces of the ancient kulturverlaengerung would live in their neural patterns, however recessive and subliminal.
We don't feel it, but our ancestors did, and we might have recessive traces of it in our kulturverlaengerung lines.
In practice, a kult'laenger linkage never really dies out--although, it can stay recessiveand unconscious.
Hence Mendel said that tallness is a dominant character, and shortness a recessive character.
He further found that all those of the second generation of crosses which displayed the recessive character bred true; that is to say, when they were bred together all their descendants exhibited this characteristic.
Latency is defined by Castle as "a condition of activity in which a normally dominant character may exist in a recessive individual or gamete.
Castle records similar phenomena in the case of guinea-pigs, and accordingly draws a distinction between recessive and latent characters.
Recessive characters are those which disappear when they come into contact with a dominant character, but reappear whenever they are separated from the opposing dominant character.
But in many instances the early recessive accent may be traced in literary Latin by the phonetic changes which it produced (102 ff.
The early recessive accent seems to have been fairly emphatic; but the stress in classical Latin was probably weak and the difference between accented and unaccented syllables was much less marked than it is in English.
The following changes took place at an early period when Latin still possessed the old, recessiveaccent (89).
In the preliterary period of the Latin language, the accent tended to go as far from the end of the word as possible (recessive accent).
The term recessive only applies to the peculiar state into which the latent character has come in the hybrid by its pairing with the antagonistic active unit.
Recessive characters are shown by those rare cases, in which hybrids revert to the varietal parent in the vegetative way.
And now," he went on, half choking with emotion, "she is apparently suffering from just the same sort of depression as I myself might suffer from if the recessive trait became active.
Then there were no recessive traits in her family," asked Kennedy quickly, "of the same sort that you find in the Athertons?
The evidence thus shows that sable is a sex-linked recessive character.
For example, the double recessive vermilion "clear" is far more easily distinguished from vermilion than is clear from red.
Since forked arose in vermilion stock, the double recessive for these two sex-linked factors could be used in testing the linkage relations of the mutation.
The daughters were back-crossed singly to the triple recessive males vermilion sable (not-bar), and gave the data included in table 14.
This account of how sable was purified shows how difficult it is to separate two recessive factors that give closely similar somatic effects.
From off-spring (F3) of the F2 yellow sable males by F2 yellow females, pure stock of the double recessive yellow sable was made up and used in the crosses to test linkage.
This shows that the mother of the original high sex-ratio was heterozygous for a recessive sex-linked lethal.
Since shifted arose in vermilion, the double recessive shifted vermilion was available for the following linkage experiment: shifted vermilion males by wild females gave wild-type males and females which inbred gave the data shown in table 46.
A previous mutation, arc, of this same type had been found to be a recessive character in the second group.
They distinguish between "dominant" and "recessive" qualities, and they establish cases in which parents with all the dominant characteristics produce offspring ofrecessive type.
Recessive qualities are constantly being masked by dominant ones and emerging again in the next generation.
In the F2 generation there were two recessive white cocks which when mature showed slight yellow colour across the loins.
When the division in the gametes of the recessiveindividual takes place its gametes all contain the recessive character.
In the case of my recessive pile, my interpretation is that when the chromosomes corresponding to two distinct characters such as colour and absence of colour are formed they do not separate from each other completely.
The two segregate in the gametes of the hybrid or heterozygote, and if a recessive gamete is fertilised by another recessive gamete the single comb reappears.
This is shown by crossing the dominant white with a recessive white, when some birds of the F(2) generation are coloured.
The condition bred true, as pure recessives do; and when such an impure recessive was mated with a heterozygote with black skin, the offspring were half pigmented and half recessive, with some pigment on the abdomen of the latter.
This is the probable explanation of the fact that the recessive white plumage has some of the pigment from the dominant form.
These were found on mating with normal specimens to be all recessive characters, thus agreeing with Bateson's views.
Since the heterozygote in F1 was deeply pigmented, it is certain that a bird with only a small amount of pigment in its skin was a recessive resulting from incomplete segregation of the pigmented character.
And then how should we account for the recessive white?
The recessive character in this case is linked to the female sex chromosome, or, as Bateson described it, the dominant character is repelled by the sex-factor.
But where a dominant characteristic encounters a recessive (Rw, wR), the recessive disappears, to make way in the individual for the dominant characteristic alone.
The definitive result is three individuals of dominant character, to one of recessive character.
Second generation: for each recessive there are three dominant: but of these only one is permanent.
The characteristic which has been shown as the stronger and more potent is victorious over the recessive characteristics that are latent in the germ.
It is possible to represent, by means of a general diagram, the mathematical succession of characteristics in hybrids, after the following manner; denoting the dominant character by D, and the recessive by r.
The hybrids belonging to the fourth group, on the contrary, are constant, like those of the first group, and are permanently of recessive character; and they will reproduce the original progenitor with white flowers.
Experiments with flowers likewise show that the recessivecolor will reappear.
Apply these widely prevalent laws to dominant man and his recessive alleged brute ancestor.
We would expect many offspring to have the recessive character of the ape, and we ought not to be surprised, if some recessive stock became permanent.
The recessive or disappearing characteristics, or the disappearing variety, will appear again, in some subsequent generation, and sometimes becomes permanent.
Else such recessive characteristics, according to the Mendelian Law, would be sure to appear.
That we find no such recessive characteristics even among the most degenerate savages, and no such ape-like tribe of human beings, is a decisive proof that man never descended from the brute.
We would also find monkeys and apes,--the recessive species--descended from man.
The recessive character was not lost, but appeared again.
This law prevails widely in nature, and the recessive traits appear with the dominant traits.
Thus, the woman of pureRecessive (the essential woman) type is smaller, more delicately organised, and weaker than the male.
While a Recessive self-fertilising plant is a female plant of superior Recessiveness, with a male plant of inferior Dominance differentiated in it.
While cells bearing Recessive traits mate with other cells bearing Recessive traits, and produce plants of pure Recessive type--Dwarf or White, like the other grandparent.
And of these, the cells bearing Dominant traits are able to transmit Dominant traits only to offspring; while the cells bearing Recessive traits transmit Recessive traits only to offspring.
Every sex-cell is a hybrid cell, therefore; bearing both Dominant andRecessive traits.
But any individual sex-cell, or gamete, cannot (according to his view) bear both Dominant and Recessive traits.
In such cases the character which appears in the hybrid was called by Mendel the dominant character and the one which disappeared the recessive character.
When crossed, all the offsprings have the constitution RA and since A isrecessive this hybrid generation resembles the pure RR parents.
Only when the black determiner is entirely absent (WW) does the white color appear in the developed organism and the individual is then said to exhibit the recessive characteristic.
If the cross had been between black hybrid guinea pigs and white recessive specimens the result would have been half hybrid blacks and half pure whites.
The results of such a mating, first between a hybrid and a recessive individual can be most easily described by considering a cross between black and white forms and expressing the result algebraically.
Such an occurrence may be nothing but the appearance of a rare recessive form.
The minor would become major, therecessive dominant.
What if the minor should become major, the recessive dominant, the obscure prevalent?
Polydactylism which is often a dominant and the web-foot of Pigeons which is recessive should be remembered as possible exceptions (see p.
In both Antirrhinum and Mirabilis it has been found that the striped may occasionally and irregularly throw self-coloured plants, and therefore the striping cannot be regarded simply as a recessive character.
It seems strange that if undecimlineata really gives off ova of this recessive type at high temperatures, the fact should not be alluded to in connection with expt.
These normals were the result of the breeding of parents declared to be at the same time giving off many recessive gametes.
The yellow is doubtless another recessive to the red.
Yellow as a recessive form of a red is certainly very common, but red and black as variants of the same pigment are less usual.
The appearance of any recessivevariety was claimed as a consequence of some treatment which might have been applied to the parents.
On the other hand the origin of a recessive variety by the loss of a factor is a process so readily imagined that our wonder is rather that the phenomenon is not observed far more often.
Similarly the black malar stripe of auratus is in all probability recessive to the red malar stripe of cafer and I imagine the pigments concerned are comparable with those in the Gouldian Finch (Poephila gouldiae) of Australia.
If the black specimens from Grenada were put with the normals which are almost certainly nothing but a recessive form of the same bird, the variation would strike the eye on even a superficial glance at the drawer.
This normal factor is recessive for notch but dominant for life.
It makes no difference whether the character in question is a dominant or a recessive one, the chance of its becoming established is exactly the same.
The preceding examples have all related to recessive characters.
Each sex is latent in the other, and each, as it contains the characters of both sexes (and can transmit those of the recessive sex) is latently hermaphrodite.
It has been shewn by Mr Norton that even if the selection exercised were slight the result in the end would be that the recessive form would entirely disappear.
The two dominant mimetic forms taken together, however, are rather more numerous than the recessive M form.
The term endocrine dominants brings up the inquiries of Mendelism, and the relation of Mendelian conceptions of dominant and recessive to the internal secretions.
Coming now to the question of recessive conditions in man, we find that defects are more likely to be of recessive than of dominant type.
According to Davenport the albinic condition is recessive to normal condition.
As a matter of fact close inspection shows that in numerous instances dominance is not absolute since traces of the recessive character may be detectable.
Some few cases have been recorded where a character is dominant at one time, recessive at another.
For example, a normal individual carrying a recessive defect will bear the abnormality in half of his or her germ-cells.
Chart showing descent of feeble-mindedness as a typical recessive (after Goddard).
Analysis by further breeding shows, however, that there are in reality three types, but since dominance is complete the pure extracted dominant and the mixed dominant-and-recessive type are indistinguishable to our eye.
If both parents have blue or gray eyes they can not have children with black or brown eyes, since therecessive condition in each parent means total absence of brown pigment in both.
Or in Mendelian phraseology, the defective traits are recessive and are dominated by the normality of the other parent.
These breed true and behave as simple recessive to agouti.
If the soma possesses the trait of the recessive to normality sort, it lacks in its germ plasm the determiner upon which the normal development depends, and this condition is called nulliplex.
And the "Simplex" type, which is the recessive form of eye-colour, breeds true.
Davenport seem to have proved the recessive character of albinism and its obedience to the Mendelian law.
In the light of present knowledge, epilepsy, considered by itself, is not a Mendelian factor, but epilepsy and feeble-mindedness are Mendelian factors of the recessive type.
