scholarly journals Why Do Birds False Alarm Flight?

Birds ◽  
2021 ◽  
Vol 3 (1) ◽  
pp. 29-37
Author(s):  
Meredith Root-Bernstein
Keyword(s):  
Natural Selection ◽  
False Alarm ◽  
Complex Terrain ◽  
Behavioural Ecology ◽  
Information Cascade ◽  
Research Traditions ◽  
Per Se ◽  
Fire Drill ◽  
The Difference ◽  
Mixed Age

False alarm flighting in avian flocks is common, and has been explained as a maladaptive information cascade. If false alarm flighting is maladaptive per se, then its frequency can only be explained by it being net adaptive in relation to some other benefit or equilibrium. However, I argue that natural selection cannot distinguish between false and true alarm flights that have similar energetic costs, opportunity costs, and outcomes. False alarm flighting cannot be maladaptive if natural selection cannot perceive the difference between true and false alarm flighting. Rather, the question to answer is what false and true alarm flighting both have in common that is adaptive per se. The fire drill hypothesis of alarm flighting posits that false alarm flights are an adaptive investment in practicing escape. The fire drill hypothesis predicts that all individuals can benefit from practicing escape, particularly juveniles. Flighting practice could improve recognition of and response time to alarm flighting signals, could compensate for inter-individual and within-day weight differences, and could aid the development of adaptive escape tactics. Mixed-age flocks with many juveniles are expected to false alarm flight more than adult flocks. Flocks that inhabit complex terrain should gain less from escape practice and should false alarm flight less. Behavioural ecology framings can be fruitfully complemented by other research traditions of learning and behaviour that are more focused on maturation and motor learning processes.

scholarly journals Reproducibility and Instruction Following in the Shop Floor Laboratory Work: The Case of a TMS Experiment

2021 ◽  
pp. 016224392110323
Author(s):  
Kristina Popova
Keyword(s):  
Measurement Procedure ◽  
Shop Floor ◽  
Experimental Uncertainty ◽  
Local Measurement ◽  
Replication Crisis ◽  
History Of ◽  
Per Se ◽  
The Difference ◽  
Methodological Guidelines ◽  
Local Procedure

The article addresses the production of reproducibility as a topic that has become acutely relevant in the recent discussions on the replication crisis in science. It brings the ethnomethodological stance on reproducibility into the discussions, claiming that reproducibility is necessarily produced locally, on the shop floor, with methodological guidelines serving as references to already established practices rather than their origins. The article refers to this argument empirically, analyzing how a group of novice neuroscientists performs a series of measurements in a transcranial magnetic stimulation experiment. Based on ethnography and video analysis, the article traces a history of the local measurement procedure invented by the researchers in order to overcome the experimental uncertainty. The article aims to demonstrate (1) how reproducibility of the local procedure is achieved in the shop floor work of the practitioners and (2) how the procedure becomes normalized and questioned as incorrect in the course of experimental practice. It concludes that the difference between guidelines and practical actions is not problematic per se; what may be problematic is that researchers can be engaged in different working projects described by the same instruction.

scholarly journals Modified S2CVA Algorithm Using Cross-Sharpened Images for Unsupervised Change Detection

2018 ◽  
Vol 10 (9) ◽  
pp. 3301 ◽  
Author(s):  
Honglyun Park ◽  
Jaewan Choi ◽  
Wanyong Park ◽  
Hyunchun Park
Keyword(s):  
Change Detection ◽  
False Alarm ◽  
False Alarm Rate ◽  
Seasonal Effects ◽  
Detection Accuracy ◽  
Difference Image ◽  
Before And After ◽  
Change Detection Algorithms ◽  
The Difference ◽  
Direction Information

This study aims to reduce the false alarm rate due to relief displacement and seasonal effects of high-spatial-resolution multitemporal satellite images in change detection algorithms. Cross-sharpened images were used to increase the accuracy of unsupervised change detection results. A cross-sharpened image is defined as a combination of synthetically pan-sharpened images obtained from the pan-sharpening of multitemporal images (two panchromatic and two multispectral images) acquired before and after the change. A total of four cross-sharpened images were generated and used in combination for change detection. Sequential spectral change vector analysis (S2CVA), which comprises the magnitude and direction information of the difference image of the multitemporal images, was applied to minimize the false alarm rate using cross-sharpened images. Specifically, the direction information of S2CVA was used to minimize the false alarm rate when applying S2CVA algorithms to cross-sharpened images. We improved the change detection accuracy by integrating the magnitude and direction information obtained using S2CVA for the cross-sharpened images. In the experiment using KOMPSAT-2 satellite imagery, the false alarm rate of the change detection results decreased with the use of cross-sharpened images compared to that with the use of only the magnitude information from the original S2CVA.

Revisiting Hull's Evolutionary Model of Science

2021 ◽  
Vol 13 (2) ◽  
pp. 145-152
Author(s):  
Mohammad Mahdi Hatef ◽  
Keyword(s):  
Natural Selection ◽  
Selection Process ◽  
Biological Evolution ◽  
Evolutionary Model ◽  
Scientific Change ◽  
Evolutionary Models ◽  
Natural Evolution ◽  
The Difference

Evolutionary models for scientific change are generally based on an analogy between scientific changes and biological evolution. Some dissimilarity cases, however, challenge this analogy. An issue discussed in this essay is that despite natural evolution, which is currently considered to be non-globally progressive, science is a phenomenon that we understand as globally progressive. David Hull's solution to this disanalogy is to trace the difference back to their environments, in which processes of natural selection and conceptual selection occur. I will provide two arguments against this solution, showing that Hull's formulation of natural selection prohibits him from removing the environment from the selection process. Then I point to a related tension in his theory, between realism and externalism in science, and give some suggestions to solve these tensions.

Adaptation and Natural Selection

2021 ◽  
pp. 125-154
Author(s):  
Áki J. Láruson ◽  
Floyd A. Reed
Keyword(s):  
Natural Selection ◽  
Allele Frequency ◽  
Levels Of Selection ◽  
Frequency Data ◽  
Selection Coefficient ◽  
Frequency Distributions ◽  
Single Allele ◽  
Selection Strength ◽  
The Difference ◽  
Over Time

Here non-random shifts in allele frequencies over time are introduced, as well as how to incorporate varying levels of selection into a model of a single population through time. This chapter highlights the difference between weak and strong selection, the dynamics of single allele versus genotype-level selection, and how selection strength and population size affect allele frequency distributions over time. Finally the inference of the selection coefficient from allele frequency data is discussed, alongside the concepts of overdominance and underdominance.

Effect of pH on metabolism of alpha-ketoglutarate by renal cortical mitochondria

1981 ◽  
Vol 240 (2) ◽  
pp. F120-F126 ◽  
Author(s):  
R. L. Tannen ◽  
A. S. Kunin
Keyword(s):  
Low Ph ◽  
Alkaline Ph ◽  
Glutamine Concentration ◽  
Acid Base ◽  
Experimental Conditions ◽  
Effect Of Ph ◽  
Adaptive Changes ◽  
Overall Response ◽  
Per Se ◽  
The Difference

The effect of acid-base perturbations on mitochondrial alpha-ketoglutarate (alpha-KG) metabolism was quantitated by measuring the nitrogen and carbon metabolites of glutamine. alpha-KG metabolized was calculated as the difference between alpha-KG production from glutamine (glutamate deamination plus transamination) and alpha-KG accumulation in the medium. Under all experimental conditions accumulation in the medium of malate plus aspartate was altered similarly to the calculated change in alpha-KG metabolism. Mitochondria from rats with chronic acidosis were compared to pair-fed controls. Chronic acidosis resulted in increased alpha-KG production and its intramitochondrial concentration; the rate of conversion of alpha-KG to succinate was unchanged. When mitochondria from normal animals were incubated at pH 7.0, 7.4, and 7.7, the amount of alpha-KG metabolized was altered, but the magnitude and direction of the response was dependent on the concentration of glutamine (0.5, 1.0, or 5.0 mM). A low pH depressed production but stimulated the subsequent metabolism of alpha-KG, whereas an alkaline pH acted in the opposite fashion. The overall response at a given glutamine concentration depended on which effect predominated. Accordingly, chronic acidosis does not induce adaptive changes, but pH, per se, directly alters intramitochondrial alpha-KG metabolism.

Metabolic Responses to Thermal Stressors of Altitude-Acclimated Rats

1958 ◽  
Vol 195 (3) ◽  
pp. 739-743 ◽  
Author(s):  
Henry B. Hale ◽  
Roy B. Mefferd
Keyword(s):  
Urine Volume ◽  
Temperature Response ◽  
Ground Level ◽  
Metabolic Responses ◽  
Control Group ◽  
Response Curves ◽  
Level Pressure ◽  
Metabolic Functions ◽  
Per Se ◽  
The Difference

Fasting 24-hour exposures of altitude-acclimated rats (380 mm Hg, 18,000 ft. simulated) to ground level pressure (750 mm Hg) at either cold (3°C), neutral (24°C), or hot (35°C) temperatures seldom resulted in return of their metabolic functions to preacclimative ‘normalcy.’ Although the control and altitude-acclimated groups both were accustomed to neutral temperatures (24° and 26°C), quantitative differences at ground level and altitude occurred in various indices of water, mineral and nitrogen metabolism. Of the 32 physiologic variables studied, only 4 (ratio of urine volume/ water intake, and urinary excretion of potassium, creatinine and glycine) failed to differentiate the responses of the altitude- and ground-accustomed rats. The temperature response curves of the altitude group tended to parallel the corresponding ones for the control group, but most variables were on higher or lower planes. The difference in plane resulted either from the effects of the return to ground level pressure, or from nonreversible effects of acclimation to altitude per se.

Activity and energy expenditure in laying hens: 3. The energy cost of eating and posture

1976 ◽  
Vol 87 (1) ◽  
pp. 85-88 ◽  
Author(s):  
M. Van Kampen
Keyword(s):  
Energy Expenditure ◽  
Spontaneous Activity ◽  
Heat Production ◽  
Energy Cost ◽  
Laying Hens ◽  
The Mean ◽  
Per Se ◽  
The Difference

SummaryThe influence of standing, spontaneous activity and eating on heat production was determined.The extra heat production of standing is negatively correlated with the length of standing period. In a short standing period of 30 min the associated activity, pecking against the respirometer wall and fluffing the feathers, was high and the heat production was increased by 25% compared with that during sitting. After standing for 1½ h spontaneous activity was very low and the difference in heat production between the standing and sitting bird was reduced by 9%.During eating the heat production increased by an average of 37% (range 11–68%); this was due mainly to the act of eating per se and not to the work of digestion.The mean energy cost of eating was calculated to be 143 J/kg0·75/min spent eating.

Seasonal Field Energetics of the Rufous Rat-Kangaroo (Aepyprymnus-Rufescens)

1992 ◽  
Vol 40 (3) ◽  
pp. 279 ◽  
Author(s):  
IR Wallis ◽  
B Green
Keyword(s):  
New South ◽  
Water Flux ◽  
Behavioural Ecology ◽  
Free Living ◽  
Doubly Labelled Water ◽  
South Wales ◽  
Poor Understanding ◽  
Males And Females ◽  
The Mean ◽  
The Difference

Water flux and field metabolic rate (FMR) were measured by the doubly labelled water (DLW) method in free-living male and female rufous rat-kangaroos Aepyprymnus rufescens near Drake in northern New South Wales. The mean FMR of 499 kJ kg-1 day-1 was similar in winter and summer even though the difference in mean minimum temperatures between the two seasons was 20-degrees-C. Furthermore, we did not find any differences in FMR between males and females even though several females carried large pouch young or had young-at-foot. A poor understanding of the diet and the behavioural ecology of A. rufescens makes ft difficult to explain the similarities between sexes and seasons.

scholarly journals FACTORS INFLUENCING THE CORRELATION BETWEEN DIFFERENCES OF ELECTRIC POTENTIAL IN THE SKIN OF HUMAN SUBJECTS AND BASAL METABOLISM

1931 ◽  
Vol 54 (6) ◽  
pp. 789-800 ◽  
Author(s):  
Charlotte Purdy ◽  
Charles Sheard
Keyword(s):  
Metabolic Rate ◽  
Electric Potential ◽  
Human Subjects ◽  
Inverse Correlation ◽  
The Body ◽  
Metabolic Rates ◽  
Electric Potentials ◽  
Per Se ◽  
The Difference ◽  
Circulation Of The Blood

High metabolic rates are associated normally with small differences of electric potential, whereas low metabolic rates are associated with large differences of electric potential as measured on the extremities of the body. Within the normal range of metabolism there appears to be a definite correlation between the metabolic rates and the difference of electric potential over a specified area of the skin, provided the person under test has no abnormalities of the circulatory system or of the functions of the skin. If there are no dysfunctions of the circulation or of the skin, the metabolic rate may be calculated, within ±4 points, from the expression See PDF for Equation where x is the metabolic rate and y is the difference of electric potential across the specified areas of skin (electrodes 12 cm. apart). In general, there are abnormalities of the circulation of the blood or of the functions of the skin of persons for whom the metabolic rates determined by the two methods (difference of electric potentials and gasometric procedures) do not agree with ±4 points. Manifest retardation or return to normality in the rate of circulation of the blood, such as may be produced by the sphygmomanometric cuff under varying pressures, produces marked changes in the difference of electric potentials obtained across a specified intervening area of skin. Retardation of flow of blood produces increased differences of electric potential. Preliminary investigations indicate that there is an inverse correlation between cutaneous temperatures and differences of electric potential. Day by day variations, emotive effects and the partaking of food have less effect, in general, on the electric potentials across a specified area of skin than they have on the metabolic rates. These experimental results indicate that there may be a more direct correlation between electric potentials and the circulation of the blood per se than between electric potentials and the metabolism of the body per se. When normality of circulation of the blood and of the functions of the skin exists in the areas under test for differences of electric potential, there is apparently a correlation between metabolic rates and electric potentials.

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