GLORIA

GEOMAR Library Ocean Research Information Access

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
Filter
  • Oligonucleotide hydridization in situ  (1)
  • inter-theoretical-relation  (1)
  • male size polymorphism  (1)
  • 1990-1994  (3)
Document type
Publisher
Years
  • 1990-1994  (3)
Year
  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Journal for general philosophy of science 24 (1993), S. 275-292 
    ISSN: 1572-8587
    Keywords: utility theory ; learning theory ; inter-theoretical-relation ; theory-comparison ; theoretical idealization ; theory approximation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Philosophy , Nature of Science, Research, Systems of Higher Education, Museum Science
    Notes: Summary Behaviourist Learning Theory and Utility Theory. Comparisons between theories are rare, especially in social theory which is believed to be a “multi-paradigmatic” science. Against this prevailing impression it is shown that there are logically reconstructable inter-theory-relations at least between different basic theories of individual action. Following Wladyslaw Krajewski a formal model of theory-approximation is developed and applied to behaviourist learning theory and utility theory. Comparing both theories leads to the result that the latter has to be preferred to Behaviourism. That utility theory has a richer content than learning theory helps to explain why George Caspar Homans explanatory programme which leans on a Skinnerian version of learning theory finally did not succeed in becoming the leading approach in social science.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 2
    ISSN: 1432-1432
    Keywords: Chromosomal sex determination ; Heterochromatin ; “Junk” DNA ; DNA fingerprinting ; Oligonucleotide hydridization in situ
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Hybridization of restriction enzymedigested genomic guppy (Poecilia reticulata, Poeciliidae) DNA with the oligonucleotide probe (GACA)4 revealed a male-specific simple tandem repeat locus, which defines the Y chromosome in outbred populations. The related (GATA)4 probe identifies certain males with the red color phenotype. In contrast only in two out of eight laboratory guppy strains was the typical (GACA)4 band observed. By specific staining of the constitutive heterochromatin one pair of chromosomes could also be identified as the sex chromosomes, confirming the XX/XY mechanism of sex determination. All males exhibit Y chromosomes with a large region of telomeric heterochromatin. Hybridization in situ with nonradioactively labeled oligonucleotide probes localized the (GACA)n repeats to this heterochromatic portion. Together these results may be regarded as a recent paradigm for the differentiation of heteromorphic sex chromosomes from a pair of autosomes during the course of evolution. According to the fish model system, this may have happened in several independent consecutive steps.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 1573-3297
    Keywords: Poeciliid fish ; male size polymorphism ; reproductive success
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Psychology
    Notes: Abstract The male-polymorphic poeciliid fish,Limia perugiae, a small teleostean endemic to the southeast of the Caribbean island Hispañola, consists of three male size morphs with uniform females. Large males differentiate at a size varying between 25 and 38 mm; intermediate males, between 21 and 25 mm. Under competition, large males exhibit an elaborate courship display, whereas small males show only a sneak-chase behavior. Intermediate males adapt their tactics to the respective competitors. However, all male morphs can switch from courtship display to sneak-chase behavior. In large mating groups with four males of different size and five or six virgin females, large dominant α-males as well as small subordinate δ-males did not produce any offspring. Unexpectedly, all progeny were sired exclusively by the intemediate subordinate β- and γ-males. Breeding experiments with the three male morphs can best be explained by a model of Y-linked genes for small and large size which are both suspended by the activity of an autosomal recessive repressor responsible for the development of intermediate males. The dominant allele of the recessive repressor, in either its homoorits heteozygous state, activates the Y-chromosomal genes for large or small size, respectively. Accordingly, intermediate males may produce male offspring of all size classes, depending on the presence of either the Y-linked gene or the autosomal repressor.
    Type of Medium: Electronic Resource
    Location Call Number Limitation Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...