Showing papers in "Journal of Genetics in 1975"
TL;DR: A few frequency models for traits affecting familial behavior are considered, in the deterministic, nonoverlapping generations case, and alternative explanations based on biological preconditions rather than the mode of inheritance are proposed for hymenopteran societies.
Abstract: This paper considers a few frequency models, in the deterministic, nonoverlapping generations case, for traits affecting familial behavior. It is assumed that a Mendelian mutant decreases the drive of offspring of either or both sexes to seek reproduction, so that they will be of more help in raising their sibs. The diploid mode of inheritance has been considered in the case of sex limited expression and equal selective effect in both sexes. In the haplodiploid case only expression limited to either sex is worked out. A selectionist interpretation in terms of different modes of inheritance had been proposed mainly by Hamilton, at a semi-quantitative level, to explain the higher incidence of social behavior in hymenopterans. There is only some limited qualitative agreement between Hamilton’s tentative results and the more orthodox treatment presented in this paper. Thus an “inclusive fitness” of genes can be defined, but only in a very special approximate case. However exactly the opposite conclusions as Hamilton’s are reached by interpreting our models both from Hamilton’s and from other, more plausible, points of view. Alternative explanations based on biological preconditions rather than the mode of inheritance are proposed for hymenopteran societies. On the other hand the reasoning in this paper might help to explain systematic differences in social behavior between mammals and birds, especially if they were determined by sex linked characters (points on which no information is available).
26 citations
TL;DR: The possibility of a stable co-existence of more than one species in a community limited by a single resource, even when the resource is being supplied uniformly in space and time, is formally demonstrated.
Abstract: The conclusion that the number of species co-existing within a biological community cannot exceed the number of limiting factors is not valid if we assume that (i) the relative efficiency of two competing species in utilizing a resource is not independent of the resource density, but one species may be more efficient at a lower density and less efficient at a higher density and (ii) there is a spatial or temporal heterogeneity in the density of the resource. This spatial or temporal heterogeneity does not have to be furnished by factors external to the biological community, but may be generated within the biological community itself as in the case of a vertical gradient of light in a plant community. This possibility of a stable co-existence of more than one species in a community limited by a single resource, even when the resource is being supplied uniformly in space and time, is formally demonstrated.
23 citations
TL;DR: The efficiency of selective breeding based on ‘phenotypic index’ which is defined as the deviation of the phenotypic value of the trait from its expected value predicted with the help of one or more auxiliary traits is discussed.
Abstract: This article discusses the efficiency of selective breeding based on ‘phenotypic index’ which is defined as the deviation of the phenotypic value of the trait from its expected value predicted with the help of one or more auxiliary traits. The conditions under which the efficiency of such a procedure is greater than one have been theoretically studied. The practical relevance of this technique has also been demonstrated by applying it to breeding data on cattle.
5 citations
TL;DR: It was shown that a balanced lethal system existed which maintained permanent translocation heterozygosity in this line and in certain families inbreeding without the production of genetically marked non-translocation homozygotes suggested that a translocation homozygote line had been isolated but, when outcrossed, all the individuals were found to be translocationheterozygotes.
Abstract: A reciprocal translocation between chromosome 2 and 3, designated T2, was viable when homozygous in the ROCK strain ofAedes aegypti. It was backcrossed five times with Delhi wild type material. Despite intensive efforts it was not possible to re-isolate it as a homozygote, indicating that a factor in the Delhi background interacted with the translocation and caused recessive lethality. In certain families inbreeding without the production of genetically marked non-translocation homozygotes suggested that a translocation homozygote line had been isolated but, when outcrossed, all the individuals were found to be translocation heterozygotes. It was shown that a balanced lethal system existed which maintained permanent translocation heterozygosity in this line.
TL;DR: Constraints represent a certain advance information I e so that the new information I' = I-I is less than L Denoting I = -S, S can be spoken of as entropy of the system, and I as negentropy (Brillouin, 1962).
Abstract: Every constraint and every additional condition imposed on the possible freedom of choice of the outcomes immediately results in a decrease of information. In other words, constraints represent a certain advance information I e so that the new information I' = I-I is less than L Denoting I = -S, S can be spoken of as entropy of the system, and I as negentropy (Brillouin, 1962). The se'cond law of thermodynamics implies that entropy S must always increase or at least remain constant.