Here the relation may be purely a quantitative one. I have repeated this experiment on Ciona and have confirmed in large half this outcome, however, sadly for the point of view, I found in other ascidians that this relation doesn’t hold. In those arthropods during which an accessory chromosome has been found we have no evidence to indicate that this chromosome is the male or the feminine aspect, and so lengthy as we know nothing in any respect in respect to the situations in the egg it is useless to speculate additional on these cases. At present we have no conclusive evidence pointing in both path. The eggs of the honey-bee extrude two polar bodies, as now we have said, and therefore are purely male. This can be a obligatory assumption, because the eggs of the bee having extruded their two polar bodies are purely male, but become female after they are fertilized. There isn’t any proof known at current supporting this assumption, however it have to be admitted that it can’t be disproved, nevertheless improbable it could seem.
The evidence on which Castle rests his assumption that there are two sorts of spermatozoa, in addition to two sorts of eggs, is contained in the next assertion: “That sex is borne by the egg is shown clearly by the case of parthenogenetic animals, which without the intervention of a male produce young of both sexes. That the spermatozoon additionally bears intercourse is manifest within the case of animals like the honey bee, for the egg of the bee, if unfertilized, invariably develops right into a male, but if fertilized into a female.” The finality of the conclusions drawn from these info is by no means above question. It has been proven in several cases by latest discoveries that the intercourse of the embryo is already determined within the fertilized egg, and in other instances it appears to be decided even earlier than fertilization, however this need not mean that there are male and female eggs, and male and female spermatozoa. Castle tries to satisfy this problem of the formation of feminine spermatozoa in a purely male individual by reference to a latest statement of Petrunkewitsch, particularly, that the reproductive organ of the male bee develops not from the egg itself, but from the second polar physique which fusing with one in all the primary pair reenters the egg.
Now we have simply examined two current theories that relaxation on assumptions of this type and have discovered, for my part, that they’re each unsatisfactory. Castle’s theory seems needlessly advanced, and the whole attempt to use the Mendelian principle to the query of sex does not appear to have been very successful. There is another side of Castle’s speculation that should be briefly referred to, since he suggests a method of assembly a issue that’s fatal to Beard’s theory. Castle is due to this fact obliged to make an additional assumption to avoid this problem. Furthermore, Castle supposes that the separation of the male from the feminine qualities of every egg takes place on the time when the second polar physique is extruded, and, in consequence, the egg and one of many polar bodies shall be female and the other two polar bodies male, or if the egg stays feminine, one polar physique will be feminine and the other two male. She didn’t make it through the second time. After serving time in jail he discovered work as a carpenter. He ended up murdering Jasmine in 2013, on the day she had planned to see her kids for the primary time in a year and a half.
If, as in the mice, all chance mixtures of the germ-cells are doable, there will outcome three sorts of people within the proportion of 2:1:1. The primary of those, which can be twice as frequent as either of the other two, would be sex-ybrids. Suppose now that these hybrids breed collectively, the white and the black spermatozoa will meet the white and the black eggs, and since it is a question of chance alone how they may come together, all potential combinations will probably be made. It’s now assumed that the germ-cells, when they reach their closing divisions, separate their male from their female elements, giving pure male and pure female eggs, and pure male and pure feminine spermatozoa. Allow us to now return to Castle’s idea and see how he tries to make an application of Mendel’s principle to sex. But why the feminine element ought to dominate in some eggs and the male in others isn’t defined, and thus we’re in exactly the identical predicament as we were before Castle’s hypothesis was proposed.