Legal proceedings, political debates, philosophical inquiry were all conducted through spoken discourse. The art of rhetoric grew out of oratory, which was the central medium for intellectual and political life in ancient Greece. It was one of five canons in classical rhetoric (the others being inventio, dispositio, elocutio, and pronuntiatio) concerned with the crafting and delivery of speeches and prose. The word is Latin, and can be translated as "memory". ![]() Godoy-Herrera and G.Memoria was the term for aspects involving memory in Western classical rhetoric. The contrasting results of these two studies are mentioned in the following untitled essaynearly four decades after their original publication. ![]() The earlier expenment failed to reveal any heterosis or its loss of following gene recombination. Robertson using body size in Drosophila subobscura, as a measure of heterosis (1963, Genetical Research 4:104-131). This study followed a corresponding one carried out in Great Britain by A. One of the supporting pieces of evidence was provided by Dobzhansky's student, Wyatt Anderson, who studied body size Drosophila pseodoobscura Ries carrying recombinant and non-recombinant chromosomes (1968, Genetical Research 12:317-330). I have provided a detailed analysis of Brncic's results in both topics in population genetics (1968) and basic population genetics (1981).Ī quarter-century ago the matter of coadaptation stirred considerable discussion. As Dobzhansky's post-doctoral student during the early 1950s, Brncic undertook to demonstrate co-adaptation within the arrowhead gene arrangement he succeeded. In effect, Dobzhansky suggested that heterosis was the outcome of natural selection, of a co-adaptation of the gene content of different gene arrangements. In contrast, flies heterozygous for inversions that come from different localities do not exhibit a corresponding heterosis. Assuming (for good reason) that equilibria revealed the selective supenority of inversion heterozygotes, Dobzhansky concluded that within a locality, inversions are co-adapted in the sense that their heterozygotes have superior fitness. In these inter-locality populations, one gene arrangement tended to displace the other. Later experiments involving chromosomes of different gene arrangements each of which came from a different geographic locality gave different results. ![]() These equilibria were established when chromosomes of the contrasting gene arrangements came from the same geographic locality. Dobzhansky and Wright had earlier reported on the equilibrium frequencies of chromosomal inversions that were established in laboratory populations of Drosophila pseudoobscura maintained at 25 ✬. I was sorry to learn recently of Danko's death.īrncic was one of Dobzhansky's early students who undertook to study "co-adaptation". Suffice it to say that during my daughter's trip to Chile where she studied the blood physiology of Humbolt penguins, Danko provided the safety net in case anything went wrong in the field: broken bones or debilitating illnesses, for example. I do not intend to write a scholarly article in memory of my friend, Danko Brncic. The Department of Biology, Virginia Polytechnic Institute and State University, 2089 Derring Hall, In Memory of Danko Brncic, a friend En memoria de Danko Brncic, un amigo
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