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1.
Proc Biol Sci ; 273(1594): 1681-8, 2006 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-16769641

RESUMO

In polygynous species with biparental care, the amount of paternal support often varies considerably. In the pied flycatcher (Ficedula hypoleuca), females mated with monogamous males receive more male assistance during the nestling phase than females mated with bigynous males, as the latter have to share their mates with another female. Bigynous males, however, give more support to their primary broods than to their secondary broods. Using a long-term dataset (31 years), the present study revealed that direct reproductive success, i.e. number of fledglings, was lower in females that mated with bigynous males, especially in secondary broods without male assistance, than in females that mated with monogamous males. Secondary broods with male assistance were more affected than primary broods. Female survival was independent of mating status. In primary broods, a delayed compensation for inferior direct reproductive success was found in terms of the number of grandoffspring, a phenomenon that did not occur in secondary broods. Delayed compensation in primary broods refers to indirect effects, i.e. good genes. According to the sexy son hypothesis, genetically superior (i.e. sexy) males may have sons with a higher number of broods belonging to a polygynous breeding status than do sons from broods with a monogamous father. This was indeed the case for sons descending from primary broods, but not for sons descending from secondary broods.


Assuntos
Comportamento Sexual Animal , Aves Canoras/fisiologia , Animais , Feminino , Masculino , Comportamento de Nidação , Reprodução , Comportamento Social , Aves Canoras/genética
2.
Cell Biol Educ ; 2(4): 256-65, 2003.
Artigo em Inglês | MEDLINE | ID: mdl-14673491

RESUMO

Two CD-ROMs from a series dealing with various major aspects of cell biology are evaluated in this paper using quantitative and qualitative approaches. The findings delimit similarities and differences of the two CD-ROMs and shed light on how the programs could be used in the learning process and how they should not be. The overall impression, as well as the graphical and technical features, received a predominantly good rating. The defined target groups were reached (e.g., students in secondary schools), different learning approaches were supported (e.g., discovery and autonomous learning), the CD-ROMs' usability was assessed as being easy and intuitive, and the majority of the evaluators were satisfied with the level of interactivity. Navigational problems encountered in CD-ROM 1 were overcome by a successful implementation of new navigational functions in CD-ROM 2. Most students found the CD-ROM to be a suitable complement to, or an extension of, their lessons. We conclude that many, but not all of the requirements for the various stages of the learning process could be satisfied with the existing CD-ROMs. The requirements not met are discussed to obtain insights that could help to improve the production of multimedia learning material. The use of quantitative and qualitative approaches in the evaluation of learning modules is discussed, as the study began by collecting and analyzing anecdotal reviews and was then extended to include a qualitative evaluation.


Assuntos
Biologia/educação , CD-ROM/normas , Fenômenos Fisiológicos Celulares , Currículo , Cloroplastos , Currículo/normas , Coleta de Dados , Estudos de Avaliação como Assunto , Alemanha , Aprendizagem , Mitocôndrias , Fotossíntese , Instituições Acadêmicas , Software/normas , Estudantes/psicologia
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