Functional nonequivalence of sperm in Drosophila pseudoobscura.
نویسندگان
چکیده
منابع مشابه
Functional nonequivalence of sperm in Drosophila pseudoobscura.
We report on a form of sperm polymorphism, termed polymegaly, that occurs in species of the Drosophila obscura group. Individual males of species in this group characteristically produce more than one discrete length of nucleated, motile sperm. Hypotheses suggested to explain the evolutionary significance of sperm polymorphism have been either nonadaptive or adaptive, with the latter focusing o...
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Spermicide (i.e., female-mediated sperm death) is an understudied but potentially widespread phenomenon that has important ramifications for the study of sexual conflict, postcopulatory sexual selection, and fertility [1, 2]. Males are predicted to evolve adaptations against spermicide, but few antispermicidal mechanisms have been definitively identified. One such adaptation may be the enigmati...
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H E linear arrangement of genes within chromosomes is constant T from generation to generation in each line of descent. The degree of this stability is comparable to that of the gene structure; genes change by mutation, chromosomes change by the occurrence of chromosomal aberrations. Strains and races of the same species, as well as distinct species, may differ in gene arrangement. One of us (S...
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ژورنال
عنوان ژورنال: Proceedings of the National Academy of Sciences
سال: 1994
ISSN: 0027-8424,1091-6490
DOI: 10.1073/pnas.91.23.11222