Morphometric and Histologic Changes in Brains of Great Blue Heron Hatchlings Exposed to PCDDs: Preliminary Analyses

Henshel, Diane S.; Km, Cheng; Norstrom, Ross J.; Whitehead, Philip E.; Steeves, J. D.

doi:10.1520/stp19246s

Cited by 26 publications

(26 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…In Apis mellifera , the right wings were shown to be larger than the left wings (Szentgyörgyi et al 2016) similar to the wings of Anthophora plumipes in our research. Directional asymmetry probably has a genetic basis (Palmer Bee size and asymmetry on a urban gradient 303 and Strobeck 1992) but environmental conditions may also contribute to it (Graham et al 1993;Henshel et al 1993;Lens and van Dongen 2000). Therefore it is possible to generate directional asymmetry by stressing an organism (Graham et al 1993;Hoffmann and Merilä 1999;Lens and Van Dongen 2000) even over a very short time period (Pélabon et al 2006).…”

Section: Modelmentioning

confidence: 99%

Body size and wing asymmetry in bees along an urbanization gradient

et al. 2017

View full text Add to dashboard Cite

-The global loss of bee diversity and abundance is a central issue in conservation biology. There is increasing evidence that cities may play an important role in bee conservation, although urbanization may also have negative impacts. Here, we investigate individual body size variation and wing asymmetry (based on 11 traits) in the solitary bee Anthophora plumipes along a rural-urban gradient in Poland. The body size of captured individuals did not show any changes along the gradient. Directional asymmetry was present, since differences between sides in 10 out of 11 traits deviated significantly from zero, with the right-side wing traits being generally larger. In contrast to our expectations, the forewing was more asymmetric in rural than in suburban and urban areas. Similarly, the absolute asymmetry of 11 wing traits (i.e. pooling differences but ignoring direction) was also significantly greater in rural than in suburban and urban landscapes. Since asymmetry may be attributed to environmental pollution and food shortages, we conclude that the urban landscape provides bees with habitats of higher quality and thus should be considered as an important habitat for bee conservation.hymenoptera / Apoidea / bees / city / directional asymmetry

show abstract

Section: Modelmentioning

confidence: 99%

Body size and wing asymmetry in bees along an urbanization gradient

et al. 2017

View full text Add to dashboard Cite

show abstract

“…Directional Asymmetry occurs when one side of a bilateral character is consistently larger than the other side (Van Valen 1962). Although DA is less associated with developmental stability (Palmer 1994), it has been found to differ between parents and their hybrid offspring (Auffray et al 1996; and transitions between FA and DA have been suggested as indicators of stress in populations (McKenzie and Clarke 1988;Graham et al 1993;Henshel et al 1993;Leamy et al 1999).…”

mentioning

confidence: 99%

The Influence of Hybridization Between African and European Honeybees, Apis Mellifera, on Asymmetries in Wing Size and Shape

et al. 2003

View full text Add to dashboard Cite

Abstract.We examined the possible role of hybridization in the invasion process of the African honeybee by testing two hypotheses regarding fluctuating asymmetry (FA), a measure of developmental stability, in wing characteristics: (1) FA should be higher in hybrid versus parental genotypes of African and European races; (2) FA should be lower in African bees compared to hybrid and European workers. Parental and reciprocal hybrid worker genotypes were cross fostered in common-hive rearing environments. We did not find greater FA for wing size and shape in the hybrids compared to both parental types. However, we did find significantly lower FA of shape in the African workers compared to the European and hybrid workers, suggesting that European bees and their hybrids may have compromised fitness relative to African bees. We also found that the two hybrid genotypes significantly differed in overall wing size and shape. If these differences affect wing aerodynamics, then the paternity of hybrids may influence worker performance and could potentially contribute to the loss of European matrilines. Hybridization had few consistent effects on directional asymmetry for wing size and shape. Genotypic factors played a far greater role in determining the effect of hybridization on wing morphology than did differences in rearing environment. Thus, African bees may have lower FA for wing shape (and by inference greater developmental stability) relative to European and hybrid workers, which may contribute to the ability of African bees to displace European honeybee races in invaded regions.

show abstract

“…Methods were as described in detail in Henshel et al (9). Briefly, two eggs from each nest were collected by the Canadian Wildlife Service.…”

Section: Methodsmentioning

confidence: 99%

Morphometric Abnormalities in Brains of Great Blue Heron Hatchlings Exposed in the Wild to PCDDs

Henshel¹,

Martin²,

Norstrom³

et al. 1995

Environmental Health Perspectives

View full text Add to dashboard Cite

Great blue heron hatchlings from colonies in the Strait of Georgia, British Columbia, Canada are being monitored for environmental contaminant exposure and effects by the Canadian Wildlife Service. The contaminants of concern are polychlorinated dibenzodioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs), primarily derived from kraft pulp mill effluent. The levels of PCDDs and PCDFs in eggs from the most contaminated colonies peaked in 1988 and 1989 and dropped dramatically through 1990 to 1992. Brains of heron hatchlings (taken as eggs from the wild and hatched in the laboratory) were analyzed for gross morphological abnormalities. Brains from highly contaminated colonies (Crofton, British Columbia and University of British Columbia Endowment Lands) in 1988 exhibited a high frequency of intercerebral asymmetry. The frequency of this abnormality decreased in subsequent years as the levels of TCDD and TCDD-TEQs (toxic equivalence factors) decreased. The asymmetry was significantly correlated with the level of TCDD and TCDD-TEQs in eggs taken from the same nest. Yolk-free body weight negatively correlated and the brain somatic index positively correlated with the TCDD level in such pair-matched eggs. These results indicate that gross brain morphology, and specifically intercerebral asymmetry, may be useful as a biomarker for the developmental neurotoxic effects of PCDDs and related chemicals.-Environ Health Perspect 103(Suppl 4): 61-66 (1995)

show abstract

Morphometric and Histologic Changes in Brains of Great Blue Heron Hatchlings Exposed to PCDDs: Preliminary Analyses

Cited by 26 publications

References 27 publications

Body size and wing asymmetry in bees along an urbanization gradient

Body size and wing asymmetry in bees along an urbanization gradient

The Influence of Hybridization Between African and European Honeybees, Apis Mellifera, on Asymmetries in Wing Size and Shape

Morphometric Abnormalities in Brains of Great Blue Heron Hatchlings Exposed in the Wild to PCDDs

Contact Info

Product

Resources

About