Within species support for the expensive tissue hypothesis: a negative association between brain size and visceral fat storage in females of the
            P
            acific seaweed pipefish

Abstract Brain size exhibits significant changes within and between species. Evolution of large brains can be explained by the need to improve cognitive ability for processing more information in changing environments. However, brains are among the most energetically expensive organs. Enlarged brains can impose energetic demands that limit brain size evolution. The expensive tissue hypothesis (ETH) states that a decrease in the size of another expensive tissue, such as the gut, should compensate for the cost of a large brain. We studied the interplay between energetic limitations and brain size evolution in small mammals using phylogenetically generalized least squares (PGLS) regression analysis. Brain mass was not correlated with the length of the digestive tract in 37 species of small mammals after correcting for phylogenetic relationships and body size effects. We further found that the evolution of a large brain was not accompanied by a decrease in male reproductive investments into testes mass and in female reproductive investment into offspring number. The evolution of brain size in small mammals is inconsistent with the prediction of the ETH.

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Evolution of vertebrate brain size is associated with sexual traits

Animal Biology ◽

10.1163/15707563-bja10039 ◽

2020 ◽

Vol 70 (4) ◽

pp. 401-416

Author(s):

Mao Jun Zhong ◽

Long Jin ◽

Jian Ping Yu ◽

Wen Bo Liao

Keyword(s):

Sexual Size Dimorphism ◽

Brain Size ◽

Finite Energy ◽

Energy Resources ◽

Testis Size ◽

Vertebrate Brain ◽

Sexual Traits ◽

The Relationship ◽

The Brain ◽

Expensive Tissue Hypothesis

Abstract The expensive tissue hypothesis predicts a trade-off between investments in the brain and other energetically costly organs due to the costs associated with their growth and maintenance within the finite energy resources available. However, few studies address the strength of relationships between brain size and investments in precopulatory (ornaments and armaments) and postcopulatory (testes and ejaculates) sexual traits. Here, in a broad comparative study, we tested the prediction that the relationship between brain size and investment in sexual traits differs among taxa relative to the importance of sperm competition within them. We found that brain size was negatively correlated with sexual size dimorphism (SSD) in anurans and primates, and it tended to decrease with SSD in ungulates and cetaceans. However, brain size did not covary significantly with armaments (e.g., canine length, horn, antler, and muscle mass). Brain size was not correlated with postcopulatory sexual traits (testes and ejaculates). The intensity of covariance between brain size and precopulatory sexual traits decreased with increasing relative testis size.

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Sucrose-sweetened beverages increase fat storage in the liver, muscle, and visceral fat depot: a 6-mo randomized intervention study

American Journal of Clinical Nutrition ◽

10.3945/ajcn.111.022533 ◽

2011 ◽

Vol 95 (2) ◽

pp. 283-289 ◽

Cited By ~ 334

Author(s):

Maria Maersk ◽

Anita Belza ◽

Hans Stødkilde-Jørgensen ◽

Steffen Ringgaard ◽

Elizaveta Chabanova ◽

...

Keyword(s):

Visceral Fat ◽

Intervention Study ◽

Fat Storage ◽

Sweetened Beverages ◽

Randomized Intervention ◽

Fat Depot ◽

Randomized Intervention Study

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No evidence for the expensive-tissue hypothesis in Fejervarya limnocharis

Animal Biology ◽

10.1163/15707563-17000094 ◽

2018 ◽

Vol 68 (3) ◽

pp. 265-276 ◽

Cited By ~ 3

Author(s):

Sheng Nan Yang ◽

Hao Feng ◽

Long Jin ◽

Zhao Min Zhou ◽

Wen Bo Liao

Keyword(s):

Brain Size ◽

Relative Size ◽

Trade Offs ◽

Size Evolution ◽

Large Brain ◽

Relative Brain Size ◽

The Cost ◽

Kidney Liver ◽

Expensive Tissue Hypothesis ◽

Fejervarya Limnocharis

AbstractBecause the brain is one of the energetically most expensive organs of animals, trade-offs have been hypothesized to exert constraints on brain size evolution. The expensive-tissue hypothesis predicts that the cost of a large brain should be compensated by decreasing size of other metabolically costly tissues, such as the gut. Here, we analyzed the relationships between relative brain size and the size of other metabolically costly tissues (i.e., gut, heart, lung, kidney, liver, spleen or limb muscles) among four Fejervarya limnocharis populations to test the predictions of the expensive-tissue hypothesis. We did not find that relative brain size was negatively correlated with relative gut length after controlling for body size, which was inconsistent with the prediction of the expensive-tissue hypothesis. We also did not find negative correlations between relative brain mass and relative size of the other energetically expensive organs. Our findings suggest that the cost of large brains in F. limnocharis cannot be compensated by decreasing size in other metabolically costly tissues.

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The energetic cost of vision and the evolution of eyeless Mexican cavefish

Science Advances ◽

10.1126/sciadv.1500363 ◽

2015 ◽

Vol 1 (8) ◽

pp. e1500363 ◽

Cited By ~ 86

Author(s):

Damian Moran ◽

Rowan Softley ◽

Eric J. Warrant

Keyword(s):

Visual System ◽

Optic Tectum ◽

Brain Size ◽

Juvenile Fish ◽

Neural Tissue ◽

Energetic Cost ◽

Metabolic Costs ◽

Resting Metabolism ◽

The Cost ◽

Expensive Tissue Hypothesis

One hypothesis for the reduction of vision in cave animals, such as the eyeless Mexican cavefish, is the high energetic cost of neural tissue and low food availability in subterranean habitats. However, data on relative brain and eye mass in this species or on any measure of the energetic cost of neural tissue are not available, making it difficult to evaluate the “expensive tissue hypothesis.” We show that the eyes and optic tectum represent significant metabolic costs in the eyed phenotype. The cost of vision was calculated to be 15% of resting metabolism for a 1-g fish, decreasing to 5% in an 8.5-g fish as relative eye and brain size declined during growth. Our results demonstrate that the loss of the visual system in the cave phenotype substantially lowered the amount of energy expended on expensive neural tissue during diversification into subterranean rivers, in particular for juvenile fish.

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Perceived Overprotection and Its Association With Quality of Life in Dementia

GeroPsych ◽

10.1024/1662-9647/a000207 ◽

2019 ◽

Vol 32 (3) ◽

pp. 125-134

Author(s):

Mechthild Niemann-Mirmehdi ◽

Andreas Häusler ◽

Paul Gellert ◽

Johanna Nordheim

Keyword(s):

Quality Of Life ◽

Patient Autonomy ◽

Positive Association ◽

Well Being ◽

Negative Association ◽

Significant Positive Association ◽

Cross Sectional ◽

People With Dementia ◽

Mental Well Being

Abstract. To date, few studies have focused on perceived overprotection from the perspective of people with dementia (PwD). In the present examination, the association of perceived overprotection in PwD is examined as an autonomy-restricting factor and thus negative for their mental well-being. Cross-sectional data from the prospective DYADEM study of 82 patient/partner dyads (mean age = 74.26) were used to investigate the association between overprotection, perceived stress, depression, and quality of life (QoL). The analyses show that an overprotective contact style with PwD has a significant positive association with stress and depression, and has a negative association with QoL. The results emphasize the importance of avoiding an overprotective care style and supporting patient autonomy.

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Domestic Integration and Suicide in the Provinces of Canada

Crisis ◽

10.1027//0227-5910.20.2.59 ◽

1999 ◽

Vol 20 (2) ◽

pp. 59-63 ◽

Cited By ~ 20

Author(s):

Antoon A. Leenaars ◽

David Lester

Keyword(s):

Social Factors ◽

Positive Association ◽

Negative Association ◽

Birth Rates ◽

Marriage Rates ◽

Suicide Rates ◽

The Social ◽

Divorce Rates ◽

Low Levels ◽

Over Time

Canada's rate of suicide varies from province to province. The classical theory of suicide, which attempts to explain the social suicide rate, stems from Durkheim, who argued that low levels of social integration and regulation are associated with high rates of suicide. The present study explored whether social factors (divorce, marriage, and birth rates) do in fact predict suicide rates over time for each province (period studied: 1950-1990). The results showed a positive association between divorce rates and suicide rates, and a negative association between birth rates and suicide rates. Marriage rates showed no consistent association, an anomaly as compared to research from other nations.

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The Negative Consequences of Stuttering for Perceptions of Leadership Ability

Journal of Individual Differences ◽

10.1027/1614-0001/a000336 ◽

2020 ◽

pp. 1-8

Author(s):

Virgil Zeigler-Hill ◽

Avi Besser ◽

Yuval Besser

Keyword(s):

Self Esteem ◽

Negative Association ◽

Negative Consequences ◽

Community Members ◽

Perceived Leadership ◽

Negative Perceptions ◽

Low Levels ◽

Perceptions Of Leadership

Abstract. The purpose of the present study was to extend previous research concerning the negative perceptions of stuttering by considering the perceived leadership ability of targets who stuttered compared with targets who did not stutter. We were also interested in the possibility that negative perceptions of the targets (i.e., low levels of self-esteem, intelligence, dominance-based status motivation, and prestige-based status motivation) would mediate the association between stuttering and a lack of perceived leadership ability as well as the possibility that manipulating the ostensible self-esteem level of the target would further moderate these associations. The results for 838 Israeli community members revealed a negative association between stuttering and perceived leadership ability that was mediated by the perceived self-esteem level and dominance-based status motivation of the target. Further, the associations between stuttering and perceptions of leadership ability were moderated by the ostensible self-esteem level of the target. Discussion focuses on the implications of these results for understanding the negative halo that surrounds stuttering.

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