Chimeras vs Genetically Homogeneous Individuals: Potential Fitness Costs and Benefits

Insects commonly harbor maternally inherited intracellular symbionts in nature, and the microbial partners often exert influence on host reproduction and fitness to promote their prevalence. Here, we investigated composition of symbionts and their biological effects in the invasive Bemisia tabaci MED species of a whitefly complex. Our field surveys revealed that populations of the MED whitefly, in addition to the primary symbiont Portiera, mainly contain two secondary symbionts Hamiltonella, which is nearly fixed in the host populations, and Cardinium with infection frequencies ranging from 0 to 86%. We isolated and established Cardinium-positive and Cardinium-free whitefly lines with a similar nuclear genetic background from a field population, and compared performance of the two whitefly lines. The infection of Cardinium incurred significant fitness costs on the MED whitefly, including reduction of fecundity and egg viability as well as delay in development. We then selectively removed Hamiltonella from the Cardinium-free whitefly line and compared performance of two whitefly lines, one harboring both Portiera and Hamiltonella and the other harboring only Portiera. While depletion of Hamiltonella had little or only marginal effects on the fecundity, developmental rate, and offspring survival, the Hamiltonella-free whitefly line produced very few female offspring, often reducing the progeny female ratio from about 50% to less than 1%. Our findings indicate that the varying costs and benefits of the association between these two symbionts and the MED whitefly may play an important role in shaping their differential prevalence in the field.

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ON THE OTHER HAND: THE COSTS AND BENEFITS OF LEFT-HANDEDNESS

Acta Neuropsychologica ◽

10.5604/01.3001.0013.1689 ◽

2019 ◽

Vol 17 (1) ◽

pp. 69-86

Author(s):

Sarah A. Fritsche ◽

Annukka K. Lindell

Keyword(s):

Substance Abuse ◽

The Other ◽

Costs And Benefits ◽

Fitness Costs ◽

Left Handedness ◽

Left Handed ◽

Other Hand ◽

Lecture Room ◽

Increased Risk ◽

Left And Right

Left-handers have been persecuted by right-handers for millennia. This right bias is evident cross-culturally, linguistically (right is literally and figuratively ‘right’, with lefties being described as ‘gauche’, ‘sinister’ and ‘cack-handed’), and environmentally (e.g., equipment design, including power tools, ticket machines, and lecture-room desks). Despite this, the proportion of left-handers has remained constant at approximately 10% of the hominid population, implying that though there are costs associated with left-handedness (if there were not, the proportions of left- and right-handers would be 50:50), left handers must also enjoy fitness advantages that maintain the genes for left-handedness in the population. This paper reviews the costs and benefits of being left-handed, exploring research examining the effects of handedness on brain structure, cognitive function, and human behaviour. The research confirms a variety of left-hander advantages, including some cognitive superiorities, higher wages, and greater sporting and fighting prowess. On the other hand, left-handedness is also associated with significant fitness costs, including an increased risk of accidents, higher substance abuse susceptibility, and earlier death, in comparison with right-handers. In sum, left-handedness confers both costs and benefits, with the latter outweighing the former, maintaining the genes for left-handedness in the population.

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HIV-1 Balances the Fitness Costs and Benefits of Disrupting the Host Cell Actin Cytoskeleton Early after Mucosal Transmission

Cell Host & Microbe ◽

10.1016/j.chom.2018.12.008 ◽

2019 ◽

Vol 25 (1) ◽

pp. 73-86.e5 ◽

Cited By ~ 6

Author(s):

Shariq M. Usmani ◽

Thomas T. Murooka ◽

Maud Deruaz ◽

Wan Hon Koh ◽

Radwa R. Sharaf ◽

...

Keyword(s):

Actin Cytoskeleton ◽

Host Cell ◽

Costs And Benefits ◽

Fitness Costs ◽

Mucosal Transmission ◽

Hiv 1

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Fitness costs and benefits of shelter building and leaf trenching behaviour in a pyralid caterpillar

Ecological Entomology ◽

10.1111/j.1365-2311.2011.01299.x ◽

2011 ◽

Vol 36 (5) ◽

pp. 564-573 ◽

Cited By ~ 12

Author(s):

MARIANA ABARCA ◽

KARINA BOEGE

Keyword(s):

Costs And Benefits ◽

Fitness Costs ◽

Leaf Trenching

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Promiscuity, paternity and personality in the great tit

Proceedings of The Royal Society B Biological Sciences ◽

10.1098/rspb.2011.1820 ◽

2011 ◽

Vol 279 (1734) ◽

pp. 1724-1730 ◽

Cited By ~ 52

Author(s):

Samantha C. Patrick ◽

Joanne R. Chapman ◽

Hannah L. Dugdale ◽

John L. Quinn ◽

Ben C. Sheldon

Keyword(s):

Risk Taking ◽

Parus Major ◽

Activity Levels ◽

Relative Importance ◽

Alternative Possibility ◽

Costs And Benefits ◽

Fitness Costs ◽

Mating Tactics ◽

Extra Pair Paternity ◽

The Social

Understanding causes of variation in promiscuity within populations remain a major challenge. While most studies have focused on quantifying fitness costs and benefits of promiscuous behaviour, an alternative possibility—that variation in promiscuity within populations is maintained because of linkage with other traits—has received little attention. Here, we examine whether promiscuity in male and female great tits ( Parus major )—quantified as extra-pair paternity (EPP) within and between nests—is associated with variation in a well-documented personality trait: exploration behaviour in a novel environment. Exploration behaviour has been shown to correlate with activity levels, risk-taking and boldness, and these are behaviours that may plausibly influence EPP. Exploration behaviour correlated positively with paternity gained outside the social pair among males in our population, but there was also a negative correlation with paternity in the social nest. Hence, while variation in male personality predicted the relative importance of paternity gain within and outside the pair bond, total paternity gained was unrelated to exploration behaviour. We found evidence that males paired with bold females were more likely to sire extra-pair young. Our data thus demonstrate a link between personality and promiscuity, with no net effects on reproductive success, suggesting personality-dependent mating tactics, in contrast with traditional adaptive explanations for promiscuity.

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