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1.
Integr Org Biol ; 4(1): obac029, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36034057

RESUMO

The adaptive significance of colorful or exaggerated traits (i.e., ornaments) expressed in females is often unclear. Competing hypotheses suggest that expression of female ornaments arises from maladaptive (or neutral) genetic inheritance from males along with incomplete epigenetic regulation, or from positive selection for ornaments in females under social competition. Whether costly or advantageous, the visibility of such traits can sometimes be behaviorally modulated in order to maximize fitness. Female eastern fence lizards express blue badges that are variable in size and color saturation. These are rudimentary compared to those seen in males and carry important costs such as reduced mating opportunities. Body temperature is a well-established enhancer of badge color, and thus thermoregulation may be one way these animals modulate badge visibility. We quantified realized body temperatures of female lizards paired in laboratory trials and observed that females with larger badges attained higher body temperatures when freely allowed to thermoregulate, sometimes beyond physiological optima. In this association between phenotype and behavior, females with larger badges exhibited thermoregulatory patterns that increase their badges' visibility. This signal-enhancing behavior is difficult to reconcile with the widely held view that female ornaments are maladaptive, suggesting they may carry context-dependent social benefits.


É muitas vezes incerta a significância adaptativa de caracteres vívidos e coloridos em fêmeas. Hipóteses para esse fenômeno sugerem uma herança maladaptativa (ou neutra) de caracteres selecionados em machos aliada à regulação epigenética incompleta em fêmeas, ou ainda seleção positiva em fêmeas imposta por competição social. Vantajosos ou não, a visibilidade de ornamentos muitas vezes é modulada por vias comportamentais do portador de modo a balancear seus custos e benefícios. Fêmeas Sceloporus undulatus possuem um par de marcas verde-azuis na parte ventral do pescoço que são variáveis em área e saturação entre indivíduos. Esses ornamentos são rudimentares em relação aos vistos em machos, mas ainda assim estão associados a custos reprodutivos importantes. Nessa espécie, temperatura corporal aumenta a visibilidade desses ornamentos significativamente. Portanto, a termorregulação é um comportamento que fêmeas poderiam empregar para modular a visibilidade de ornamentos. Nós quantificamos temperaturas corporais obtidas por pares de lagartos fêmeas em testes comportamentais e observamos que fêmeas com os maiores ornamentos também obtiveram temperaturas corporais mais altas, às vezes além do ótimo fisiológico. Nesta associação entre fenótipo e comportamento, fêmeas com os maiores ornamentos exibiram padrões de termoregulação que aumentaram sua visibilidade. Este padrão é difícil de conciliar com a perspectiva de que ornamentos são maladaptativos em fêmeas, sugerindo benefícios que são dependentes do contexto social.

2.
Acta Hortic ; 1061: 147-154, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-27156707

RESUMO

Elderberry (Sambucus spp.) is an emerging horticultural crop used in a variety of foods, wines, and dietary supplements. A better understanding of the elderberry juice complex including its putative health-promoting compounds in relation to genetic and environmental parameters is needed. A multi-location planting of nine elderberry genotypes was established in 2008 at three geographically-diverse sites in Missouri, USA. Fruits were harvested from replicated plots 2009-2011, frozen, and later prepared for laboratory analysis. Polyphenols, organic acids, and sugars were quantified by HPLC and the results evaluated for response to genotype, site, and year. The American genotypes 'Ocoee' and 'Ozark' were consistently higher in chlorogenic acids compared to other genotypes, whereas 'Ocoee' was significantly higher in rutin than 'Ozark'. The European 'Marge' was significantly higher in isoquercitrin and other flavonoids compared to most North American genotypes. Significant differences in polyphenols were also detected among sites and production years. Malic, citric, and tartaric acids varied significantly among genotypes, sites, and years, whereas succinic, shikimic, and fumaric acids generally did not. Levels of lactic, acetic, and propionic acids were negligible in most samples. The American genotype 'Ocoee' was higher in citric and tartaric acids, while lower in malic acid. The sugars glucose and fructose also responded significantly to genotype, site, and year. 'Ocoee', 'Ozark', and 'Marge' perform very well in Missouri horticulturally and appear to have additional potential as cultivars based on their unique juice characteristics.

3.
Acta Hortic ; 1061: 237-244, 2015 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-27158183

RESUMO

American elderberry (Sambucus nigra subsp. canadensis) is being increasingly cultivated in North America for its edible and medicinal fruit and flowers, yet remains largely undeveloped as a horticultural crop. Productive genotypes with desirable horticultural attributes, including disease and insect resistance, precocity, uniform fruit ripening, and large berry size are needed in order to advance the commercial production of elderberries. A four-year study of eight elderberry genotypes was established in 2008 at three diverse Missouri (USA) locations. Phenology, plant morphology, pest susceptibility, productivity, and fruit characteristics data were collected over three growing seasons, 2009-2011. Significant differences for most phenological, horticultural, and fruit juice characteristics were observed among the three sites, three years, and eight genotypes. The genotype 'Ozark' was the earliest to break bud, produced fruit with high levels of soluble solids, and out-yielded most other genotypes at the three sites over the three-year study. None of the new genotypes produced berries as large as or larger than the standard 'York' which is known for its large fruit. Some of the genotypes tested, especially 'Ozark' show promise as potential cultivars and as breeding stock for further development of elderberry as a commercially-viable horticultural crop.

4.
Acta Hortic ; 1061: 191-199, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-27182104

RESUMO

Elderberries are being increasingly produced and consumed in North America for their edible and medicinal flowers and fruits. The American elderberry (Sambucus nigra subsp. canadensis) is native to, and most often cultivated in North America. The European elderberry (S. nigra subsp. nigra) has been developed into an economically-important horticultural crop in Europe, but most European cultivars do not perform well in the midwestern USA. The genotype S. nigra subsp. nigra 'Marge' is an open-pollinated seedling of S. nigra subsp. nigra 'Haschberg', which is one of the most popular elderberry cultivars grown in Europe. In a four-year study (one establishment year followed by 3 production years; 2008-2011) at three Missouri (USA) locations, 'Marge' significantly out-performed and out-yielded eight American elderberry genotypes within the same replicated field plots. Across 3 production years at all three sites, 'Marge' achieved budbreak later, flowered earlier, suffered less Eriophyid mite damage, was taller, produced larger berries, and yielded significantly greater amounts of fruit compared with all eight American elderberry genotypes in the study. At one site, 'Marge' produced three times the yield (1.89 kg/plant) compared with the next highest-producing American elderberry genotype (0.65 kg/plant). It is an exceptionally robust and drought-resistant elderberry. The phenotypic attributes of 'Marge' are similar to that of European elderberry except that it performs exceptionally well in the midwestern USA. DNA marker results, along with phenological and morphological characteristics, indicate that 'Marge' is a European elderberry (S. nigra subsp. nigra). As with most European genotypes, 'Marge' does not fruit on first-year wood, and will therefore require a different pruning regimen compared with American elderberry for success in North American production. We do not yet know how 'Marge' will perform outside the midwestern USA, but it is so productive, unique, and mite resistant, that it merits introduction as a cultivar.

5.
J Acoust Soc Am ; 99(6): 3738-48, 1996 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-8655805

RESUMO

This study compared samples of less-masculine-sounding (LMS) and more-masculine-sounding (MMS) male speech to identify acoustic characteristics, other than fundamental frequency, that might contribute to the perception of these categories. In the first phase, audiorecorded speech samples provided by 35 males were presented to 35 female listeners in a paired-comparison perceptual experiment. Nineteen of the male speech samples were judged reliably to fall within the LMS or MMS categories. Within those 19 samples, 8 speakers (4 LMS and 4 MMS) exhibited similar distributions of habitual fundamental frequency values in connected speech and in sustained phonation. In the second phase of the experiment, various acoustic measures of these eight connected speech samples were conducted. Significant differences between measures of fundamental frequency contours, vowel formant midpoint values, and in the first, third and fourth spectral moments of two fricatives were revealed. These findings may be useful in creating stylized synthetic speech that varies on the dimension of masculinity, and they may have clinical relevance for patients wishing to modify the perception of masculinity invoked by their speech.


Assuntos
Fonética , Acústica da Fala , Fala , Adulto , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fatores Sexuais , Medida da Produção da Fala
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