Multigenerational exposure to elevated temperatures leads to a reduction in standard metabolic rate in the wild

The schooling behaviour of fish is of great biological importance, playing a crucial role in the foraging and predator avoidance of numerous species. The extent to which physiological performance traits affect the spatial positioning of individual fish within schools is completely unknown. Schools of juvenile mullet Liza aurata were filmed at three swim speeds in a swim tunnel, with one focal fish from each school then also measured for standard metabolic rate (SMR), maximal metabolic rate (MMR), aerobic scope (AS) and maximum aerobic swim speed. At faster speeds, fish with lower MMR and AS swam near the rear of schools. These trailing fish required fewer tail beats to swim at the same speed as individuals at the front of schools, indicating that posterior positions provide hydrodynamic benefits that reduce swimming costs. Conversely, fish with high aerobic capacity can withstand increased drag at the leading edge of schools, where they could maximize food intake while possibly retaining sufficient AS for other physiological functions. SMR was never related to position, suggesting that high maintenance costs do not necessarily motivate individuals to occupy frontal positions. In the wild, shifting of individuals to optimal spatial positions during changing conditions could influence structure or movement of entire schools.

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Multigenerational exposure to elevated temperatures leads to a reduction in standard metabolic rate in the wild

10.1101/749986 ◽

2019 ◽

Author(s):

Natalie Pilakouta ◽

Shaun S. Killen ◽

Bjarni K. Kristjánsson ◽

Skúli Skúlason ◽

Jan Lindström ◽

...

Keyword(s):

Climate Change ◽

Gene Flow ◽

Metabolic Rate ◽

Elevated Temperatures ◽

General Pattern ◽

Standard Metabolic Rate ◽

List Type ◽

Geographic Scale ◽

Lower Standard ◽

Warming World

AbstractIn light of global climate change, there is a pressing need to understand and predict the capacity of populations to respond to rising temperatures. Metabolic rate is a key trait that is likely to influence the ability to cope with climate change. Yet, empirical and theoretical work on metabolic rate responses to temperature changes has so far produced mixed results and conflicting predictions.Our study addresses this issue using a novel approach of comparing fish populations in geothermally warmed lakes and adjacent ambient-temperature lakes in Iceland. This unique ‘natural experiment’ provides repeated and independent examples of populations experiencing contrasting thermal environments for many generations over a small geographic scale, thereby avoiding the confounding factors associated with latitudinal or elevational comparisons. Using Icelandic sticklebacks from three warm and three cold habitats, we measured individual metabolic rates across a range of acclimation temperatures to obtain reaction norms for each population.We found a general pattern for a lower standard metabolic rate in sticklebacks from warm habitats when measured at a common temperature, as predicted by Krogh’s rule. Metabolic rate differences between warm- and cold-habitat sticklebacks were more pronounced at more extreme acclimation temperatures, suggesting the release of cryptic genetic variation upon exposure to novel conditions, which can reveal hidden evolutionary potential. We also found a stronger divergence in metabolic rate between thermal habitats in allopatry than sympatry, indicating that gene flow may constrain physiological adaptation when dispersal between warm and cold habitats is possible.In sum, our study suggests that fish may diverge toward a lower standard metabolic rate in a warming world, but this might depend on connectivity and gene flow between different thermal habitats.

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Field-Testing a Standard Metabolic Rate Estimation Technique for Eastern Red-Backed Salamanders

Journal of Herpetology ◽

10.1670/14-159 ◽

2016 ◽

Vol 50 (1) ◽

pp. 138-144

Author(s):

Patrick J Ruhl ◽

Robert N Chapman ◽

John B. Dunning

Keyword(s):

Metabolic Rate ◽

Field Testing ◽

Standard Metabolic Rate ◽

Estimation Technique ◽

Rate Estimation

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Aspergillus nidulans Protein O-Mannosyltransferases Play Roles in Cell Wall Integrity and Developmental Patterning

Eukaryotic Cell ◽

10.1128/ec.00040-09 ◽

2009 ◽

Vol 8 (10) ◽

pp. 1475-1485 ◽

Cited By ~ 33

Author(s):

Thanyanuch Kriangkripipat ◽

Michelle Momany

Keyword(s):

Cell Wall ◽

Aspergillus Nidulans ◽

Double Mutant ◽

Elevated Temperatures ◽

Cell Wall Integrity ◽

Wild Type ◽

Spatial Cues ◽

Developmental Patterning ◽

In The Wild ◽

Increased Sensitivity

ABSTRACT Protein O-mannosyltransferases (Pmts) initiate O-mannosyl glycan biosynthesis from Ser and Thr residues of target proteins. Fungal Pmts are divided into three subfamilies, Pmt1, -2, and -4. Aspergillus nidulans possesses a single representative of each Pmt subfamily, pmtA (subfamily 2), pmtB (subfamily 1), and pmtC (subfamily 4). In this work, we show that single Δpmt mutants are viable and have unique phenotypes and that the ΔpmtA ΔpmtB double mutant is the only viable double mutant. This makes A. nidulans the first fungus in which all members of individual Pmt subfamilies can be deleted without loss of viability. At elevated temperatures, all A. nidulans Δpmt mutants show cell wall-associated defects and increased sensitivity to cell wall-perturbing agents. The Δpmt mutants also show defects in developmental patterning. Germ tube emergence is early in ΔpmtA and more frequent in ΔpmtC mutants than in the wild type. In ΔpmtB mutants, intrahyphal hyphae develop. All Δpmt mutants show distinct conidiophore defects. The ΔpmtA strain has swollen vesicles and conidiogenous cells, the ΔpmtB strain has swollen conidiophore stalks, and the ΔpmtC strain has dramatically elongated conidiophore stalks. We also show that AN5660, an ortholog of Saccharomyces cerevisiae Wsc1p, is modified by PmtA and PmtC. The Δpmt phenotypes at elevated temperatures, increased sensitivity to cell wall-perturbing agents and restoration to wild-type growth with osmoticum suggest that A. nidulans Pmts modify proteins in the cell wall integrity pathway. The altered developmental patterns in Δpmt mutants suggest that A. nidulans Pmts modify proteins that serve as spatial cues.

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A whole genome analysis of the red-crowned crane provides insight into avian longevity

10.1101/188656 ◽

2017 ◽

Author(s):

HyeJin Lee ◽

Oksung Chung ◽

Yun Sung Cho ◽

Sungwoong Jho ◽

JeHoon Jun ◽

...

Keyword(s):

Metabolic Rate ◽

Whole Genome ◽

Whole Genome Analysis ◽

Grus Japonensis ◽

Low Genetic Diversity ◽

In Captivity ◽

In The Wild ◽

Genetic Mechanisms ◽

Avian Genomes ◽

Insight Into

AbstractThe red-crowned crane (Grus japonensis) is an endangered and large-bodied crane native to East Asia. It is a traditional symbol of longevity and its long lifespan has been confirmed both in captivity and in the wild. Lifespan in birds is positively correlated with body size and negatively correlated with metabolic rate; although the genetic mechanisms for the red-crowned crane’s long lifespan have not previously been investigated. Using whole genome sequencing and comparative evolutionary analyses against the grey-crowned crane and other avian genomes, we identified candidate genes that are correlated with longevity. Included among these are positively selected genes with known associations with longevity in metabolism and immunity pathways (NDUFA5, NDUFA8, NUDT12 IL9R, SOD3, NUDT12, PNLIP, CTH, and RPA1). Our analyses provide genetic evidence for low metabolic rate and longevity, accompanied by possible convergent adaptation signatures among distantly related large and long-lived birds. Finally, we identified low genetic diversity in the red-crowned crane, consistent with its listing as an endangered species, and we hope this genome will provide a useful genetic resource for future conservation studies of this rare and iconic species.

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Energy expenditure for thermoregulation and locomotion in emperor penguins

American Journal of Physiology-Legacy Content ◽

10.1152/ajplegacy.1976.231.3.903 ◽

1976 ◽

Vol 231 (3) ◽

pp. 903-912 ◽

Cited By ~ 77

Author(s):

B Pinshow ◽

MA Fedak ◽

DR Battles ◽

K Schmidt-Nielsen

Keyword(s):

Metabolic Rate ◽

Energy Requirement ◽

Thermal Conductance ◽

Standard Metabolic Rate ◽

High Energy ◽

Breeding Cycle ◽

Emperor Penguin ◽

Energy Reserves ◽

Ambient Temperatures ◽

Emperor Penguins

During the antarctic winter emperor penguins (Aptenodytes forsteri) spend up to four mo fasting while they breed at rookeries 80 km or more from the sea, huddling close together in the cold. This breeding cycle makes exceptional demands on their energy reserves, and we therefore studied their thermoregulation and locomotion. Rates of metabolism were measured in five birds (mean body mass, 23.37 kg) at ambient temperatures ranging from 25 to -47 degrees C. Between 20 and -10 degrees C the metabolic rate (standard metabolic rate (SMR)) remained neraly constant, about 42.9 W. Below -10 degrees C metabolic rate increased lineraly with decreasing ambient temperature and at -47 degrees C it was 70% above the SMR. Mean thermal conductance below -10 degrees C was 1.57 W m-2 degrees C-1. Metabolic rate during treadmill walking increased linearly with increasing speed. Our data suggest that walking 200 km (from the sea to the rookery and back) requires less than 15% of the energy reserves of a breeding male emperor penguin initially weighing 35 kg. The high energy requirement for thermoregulation (about 85%) would, in the absence of huddling, probably exceed the total energy reserves.

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Mitochondrial Proton Conductance, Standard Metabolic Rate and Metabolic Depression

Life in the Cold ◽

10.1007/978-3-662-04162-8_44 ◽

2000 ◽

pp. 413-430 ◽

Cited By ~ 4

Author(s):

Martin D. Brand ◽

Tammie Bishop ◽

Robert G. Boutilier ◽

Julie St-Pierre

Keyword(s):

Metabolic Rate ◽

Standard Metabolic Rate ◽

Metabolic Depression ◽

Proton Conductance

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The opposite effects of routine metabolic rate and metabolic rate during startle responses on variation in the predictability of behaviour in hermit crabs

Behaviour ◽

10.1163/1568539x-00003371 ◽

2016 ◽

Vol 153 (13-14) ◽

pp. 1545-1566 ◽

Cited By ~ 8

Author(s):

Mariana Velasque ◽

Mark Briffa

Keyword(s):

Metabolic Rate ◽

Generalized Linear Models ◽

Startle Response ◽

Linear Models ◽

Elevated Temperatures ◽

Hermit Crabs ◽

Routine Metabolic Rate ◽

Intraindividual Variation ◽

The Mean ◽

Pagurus Bernhardus

Studies on animal behaviour have suggested a link between personality and energy expenditure. However, most models assume constant variation within individuals, even though individuals vary between observations. Such variation is called intraindividual variation in behaviour (IIV). We investigate if IIV in the duration of the startle response is associated with metabolic rates (MR) in the hermit crabPagurus bernhardus. We repeatedly measured startle response durations and MR during each observation. We used double hierarchical generalized linear models to ask whether among and IIV in behaviour was underpinned by MR. We found no association between the mean duration of the startle responses and either routine MR or MR during startle response. Nevertheless, we found that IIV increased with MR during startle responses and decreased with routine MR. These results indicate that crabs with higher MR during startle responses behave less predictably, and that predictability is reduced during exposure to elevated temperatures.

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Aspects of the Use of Den Trees by Arboreal and Scansorial Marsupials Inhabiting Montane Ash Forests in Victoria

Australian Journal of Zoology ◽

10.1071/zo9910057 ◽

1991 ◽

Vol 39 (1) ◽

pp. 57 ◽

Cited By ~ 30

Author(s):

DB Lindenmayer ◽

RB Cunningham ◽

MT Tanton ◽

HA Nix

Keyword(s):

Metabolic Rate ◽

Standard Metabolic Rate ◽

The Body ◽

Large Species ◽

Strongly Correlated ◽

Emergence Time ◽

Significant Preference ◽

Field Metabolic Rate ◽

Arboreal Marsupials ◽

Selection Of

The time and height of emergence from den trees occupied by various species of arboreal marsupials inhabiting the montane ash forests of the Central Highlands of Victoria, in south-east Australia, were recorded from September 1988 to January 1989. There were significant differences in emergence time among most species of arboreal marsupials. Emergence time was strongly correlated with published values of body weight, field metabolic rate and standard metabolic rate. The entrance to the nest was higher in gliding species than those which are non-volant. Small species exhibited a significant preference for den sites with a hole as the entrance. The entrance of a den occupied by large species was typically a hole in a hollow branch or spout. The selection of den sites was related to the body size of the occupant. Differences in the type and height of the entrance to the nest, together with the time of emergence from the den, indicate partitioning of the nest tree resource between the various species inhabiting montane ash forests.

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Flight Energetics of Free-Living Sooty Terns

The Auk ◽

10.1093/auk/101.2.288 ◽

1984 ◽

Vol 101 (2) ◽

pp. 288-294 ◽

Cited By ~ 52

Author(s):

Elizabeth N. Flint ◽

Kenneth A. Nagy

Keyword(s):

Metabolic Rate ◽

Standard Metabolic Rate ◽

Co2 Production ◽

Doubly Labeled Water ◽

Free Living ◽

Aspect Ratios ◽

Flight Energetics ◽

Flight Metabolism ◽

Sooty Tern ◽

Free Ranging

Abstract The CO2 production of free-ranging Sooty Terns (Sterna fuscata) was measured using doubly labeled water (HTO-18). Metabolic rate during flight was determined to be 4.8 times standard metabolic rate (SMR). This value is much lower than estimates of flight metabolism predicted from previously published equations. Observations of these birds at sea indicate that flapping flight predominated at the windspeeds (0-5 m/s) that prevailed during our measurement periods, so factors other than gliding must account for the comparatively low flight metabolism we measured. Sooty Tern flight metabolism is similar to that of some other birds, such as swallows and swifts, that also have high aspect ratios and low wing loadings.

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