phenomenon · claim-type · cross-domain-transfer · mechanism · claim-relation · replication-status · limitation — grounded in the full text| phenomenon | heterosis in chromosomal inversion heterozygotes— “In contrast to this, inversion heterozygotes which carry two chromosomes of different geographic origin usually show no heterosis.” | |
| claim-type | mechanism— “The heterosis is produced, in these cases, by interaction of polygene complexes, which have become mutually adjusted, or coadapted, by natural selection in the course of the evolutionary process.” | |
| method — evidence | — “Population cages of the type described by WRIGHT and DOBZHANSKY (1946), but somewhat improved in construction, were used.” | |
| mechanism | Natural selection coadapts polygene complexes only within a population, so chromosomes brought together from populations that never interbreed have not been mutually adjusted and their heterozygotes lack heterosis.— “Natural selection may have produced different polygene complexes in different populations, coadapted within but not be tween the populations. If this hypothesis is corr~ct, inversion heterozygotes which carry two chromosomes derived from different populations may not show as much heterosis as is observed within these populations… | mechanisms[0] |
| mechanism | Heterosis arises from interaction between polygene complexes carried by differently arranged chromosomes, which the inversions protect from being broken up by crossing over in the heterozygote.— “Heterosis is here the outcome of interaction of polygene complexes borne in the chromosomes with different gene arrangements and protected by the inversions from disintegration by crossing over in the heterozygotes.” | mechanisms[1] |
| mechanism | A second, distinct kind of heterosis arises when deleterious recessive mutants accumulated in the population are sheltered by their normal dominant alleles in the heterozygote.— “The first kind arises from the presence in populations of deleterious recessive mutant genes shel tered by their normal dominant alleles.” | mechanisms[2] |
| mechanism | Viability and adaptive value diverge because larval survival is only one of several components (adult longevity, fecundity, sexual activity) that jointly determine net fitness.— “The answer is that the relative viability under competition is only one of the variables which determine the adaptive value of a genotype.” | mechanisms[3] |
| builds-on | Wright and Dobzhansky (1946) and Dobzhansky (1947a, b) population-cage results on within-population heterosis— “Indeed, experimental populations kept in so-called "population cages" have shown that the inversion heterozygotes which carry two third chromosomes with different gene arrangements derived from the same population are superior in fitness to the corresponding homozygotes (WRIGHT and DOBZHANSKY 1946; DOBZHANSKY 1947 a, b).” | claim_relations[0] |
| sense | heterosis - KIND ONE, AN ACCIDENT OF MUTATION: superiority arising because deleterious recessive mutants are hidden by their dominant alleles, which is a by-product of the mutation process— “The first kind arises from the presence in populations of deleterious recessive mutant genes shel tered by their normal dominant alleles.” | senses[0] |
| sense | heterosis - KIND TWO, A PRODUCT OF SELECTION: specific interaction effects from complexes of linked polygenes, called overdominance, engendered by natural selection as adaptation— “The second kind of heterosis is due to complexes of linked polygenes which give specific "heterotic" interaction effects in heterozygotes” | senses[1] |
| sense | adaptive value - AS FREQUENCY CHANGE IN A CAGE: not a physiological measurement but the observed change in the relative frequencies of two types over time in a population cage— “The adaptive values are determined, in our experiments, by observing the changes in the relative frequencies of the two types with time in popula tions breeding in population cages.” | senses[2] |
| control | inversion heterozygotes compared against inversion homozygotes, with the paper noting that the heterozygotes were also heterozygous for geographical gene complexes — partial — rules out very little on its own - and the paper says so, which is why this is worth recording: it names the confound its own comparison does not remove— “If so, in the experiments so far described, we compared inversion heterozygotes, which were also heterozygous for geographical gene complexes, with inversion homozygotes which carried third chromosomes of similar geo graphic origin.” | controls[0] |
| edge | polygene complexes —causes→ heterosis— “The heterosis is produced, in these cases, by interaction of polygene complexes, which have become mutually adjusted, or coadapted, by natural selection in the course of the evolutionary process” | concept_edges[0] |
| edge | euheterosis —distinct-from→ luxuriance— “it is clear that the mechanisms underlying euheterosis and luxuriance are quite different. Euheterosis is a product of mutation and selection pressures” | concept_edges[1] |
| audit | EVIDENCE CORRECTED (RE-GROUNDED) · adaptive value —operationalised-as→ population cages — Audit 2026-09-28: DOUBTFUL - read against its full span and kept, but adaptive values are DETERMINED by observing frequencies in population cages; operationalised-as is loose.— “The adaptive values are determined, in our experiments, by observing the changes in the relative frequencies of the two types with time in popula tions breeding in population cages.” | concept_edges[2] |
| retracted | EVIDENCE CORRECTED (RE-GROUNDED) · adaptive value —operationalised-as→ population cages — RE-GROUNDED. Same sentence, CARRIED TO ITS END. The old span stopped at 'observing the…' and lost the apparatus; the full sentence finishes '…breeding in POPULATION CAGES…', which is the operationalisation the edge records. The broken word 'popula tions' is the staged text's own and is quoted as it stands.— “The adaptive values are determined, in our experiments, by observing the changes in the relative frequencies of the two types with time in popula tions breeding in population cages.”— “The adaptive values are determined, in our experiments,” | concept_edges[2] |
| outcome (stated by the tagger, no quotation) | control — partial | controls[0] |
| for which use | limitation — the elimination prediction specifically: THE CH CHROMOSOMES WERE RARE IN CAGES NOS. 48 AND 49, BUT MUCH LONGER OBSERVATION WOULD BE NEEDED TO SEE THEM ELIMINATED COMPLETELY— “At the end of the experiments, the CH chromosomes were rare in cages Nos. 48 and 49, but much longer observation would be needed to see them eliminated completely.” | limitations[0] |
| for which use | limitation — the viability comparison in cage No. 55: THE DIFFERENCES ARE, HOWEVER, MOSTLY BELOW THE CONVENTIONAL LEVEL OF STATISTICAL SIGNIFICANCE— “The differences are, however, mostly below the conventional level of statistical significance.” | limitations[1] |
| for which use | limitation — any result reported as heterosis or hybrid vigor: the paper states these terms are common names for a group of scarcely related phenomena, so two such results need not be about the same thing— “are common names for a group of scarcely related phenomena” | limitations[2] |
| for which use | limitation — a fitness or survival figure from a single developmental stage: adaptive value is stated not to be proportional to survival value at all stages, and here some types with higher egg-to-adult mortality were nevertheless adaptively superior— “The adaptive value (net fitness) of a type is not necessarily proportional to its survival value at all… | limitations[3] |
| for which use | limitation — a heterosis result carried from one population to another: polygene complexes from geographically distant localities have not undergone coadaptation, so the same chromosomal type does not behave the same way in a different population | limitations[4] |
| replication | untested | |
| limitation | The cages were not run long enough for the inferior chromosome type to be eliminated, so the predicted outcome was not observed to completion. | limitations[0] |
| limitation | In the California-Mexico cage No. 55 the viability differences among genotypes did not reach conventional significance. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[1] |
| limitation | The paper opens its discussion by saying the term names several scarcely related phenomena that the field treats as one. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[2] |
| limitation | Fitness measured at one developmental stage can point the opposite way from fitness overall, and the paper gives its own case. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[3] |
| limitation | The effect is a property of chromosomes that evolved together, so the same gene-arrangement label does not carry the same behaviour between localities. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | limitations[4] |
finding · quantity · variable · definition · key-term — grounded in the full text| finding | Inversion heterozygotes built from two third chromosomes of the same population show heterosis, but heterozygotes built from chromosomes of geographically remote populations generally do not. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[0] |
| finding | In every experiment one homozygote was sharply less viable than the heterozygote (quotients 0.17 to 0.76). Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[1] |
| finding | Heterozygosity for same-population ST and AR third chromosomes raises viability even on a geographically mixed background of the other chromosomes. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[2] |
| finding | In both cages the adaptive values were ST/AR > ST/ST > AR/AR, the reverse of the viability relations in cage 46. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[3] |
| finding | By March 1948 Arrowhead had risen to 91 percent and Chiricahua had fallen to 9 percent. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[4] |
| finding | In cage 56 the Pinon Arrowhead homozygote was significantly more viable than the heterozygote, and the Mexican Chiricahua homozygote equally or slightly more viable. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[5] |
| finding | A type's adaptive value (net fitness) is not necessarily proportional to its survival at every developmental stage. Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.findings[6] |
| quantity | 0.17 to 0.76 — Range of viability quotients of the inferior homozygote relative to the heterozygote across the five geographically mixed cages Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[0] |
| quantity | chi-squares 6.63 to 16.05 — Range of chi-squared values testing the inferiority of the poorly viable homozygote against the heterozygote, on the pooled sexes Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[1] |
| quantity | 91 percent ... 9 percent — Frequencies of Mather Arrowhead and Pinon Chiricahua chromosomes in cage 45 by March 1948, from an equal start in February 1947 Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[2] |
| quantity | 79 percent ... 53 percent — Equilibrium frequency of Arrowhead reached in pure Pinon Flats and in pure Mather populations, against which the runaway hybrid cages are compared Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[3] |
| quantity | 1,217 — Number of AR/CH heterozygote flies introduced into population cage No. 45 at the start of the experiment Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[4] |
| quantity | 300 miles — Distance between the two Californian source localities, Mather and Pinon Flats Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[5] |
| quantity | 31:32 — Probability that both chromosomal types of a heterozygous parent are detected when six larvae are examined, implying one thirty-second of heterozygotes are misclassified as homozygotes Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.quantities[6] |
| definition | coadaptation Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[1] |
| definition | viability quotient Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.definitions[2] |
| concept | heterosis Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[0] |
| concept | euheterosis Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[1] |
| concept | luxuriance Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[2] |
| concept | adaptive value Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[3] |
| concept | polygene complexes Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[4] |
| concept | population cages Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | concepts[5] |
| chi-squared x2 | as written: computing chi-squares Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[0] |
| degrees of freedom | as written: one degree of freedom Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[1] |
| significance level | as written: the conventional level of statistical significance Quotation withheld — this paper is not ours to reproduce, and the page has already quoted as much of it as the rights layer allows. The tag, its field and its confidence stand; the sentence is at the publisher. | content_tags.statistics[2] |
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