scholarly journals Mimicry in motion and morphology: do information limitation, trade-offs or compensation relax selection for mimetic accuracy?

2021 ◽  
Vol 288 (1952) ◽  
pp. 20210815
Author(s):  
Donald James McLean ◽  
Marie E. Herberstein
Keyword(s):  
Simple Model ◽  
Incomplete Information ◽  
Complex Traits ◽  
Selection Pressure ◽  
Comparative Tests ◽  
Trade Offs ◽  
Taxonomic Range ◽  
Selection For ◽  
Imperfect Mimicry ◽  
General Explanation

Many animals mimic dangerous or undesirable prey as a defence from predators. We would expect predators to reliably avoid animals that closely resemble dangerous prey, yet imperfect mimics are common across a wide taxonomic range. There have been many hypotheses suggested to explain imperfect mimicry, but comparative tests across multiple mimicry systems are needed to determine which are applicable, and which—if any—represent general principles governing imperfect mimicry. We tested four hypotheses on Australian ant mimics and found support for only one of them: the information limitation hypothesis. A predator with incomplete information will be unable to discriminate some poor mimics from their models. We further present a simple model to show that predators are likely to operate with incomplete information because they forage and make decisions while they are learning, so might never learn to properly discriminate poor mimics from their models. We found no evidence that one accurate mimetic trait can compensate for, or constrain, another, or that rapid movement reduces selection pressure for good mimicry. We argue that information limitation may be a general principle behind imperfect mimicry of complex traits, while interactions between components of mimicry are unlikely to provide a general explanation for imperfect mimicry.

scholarly journals Selection for Reinforcement-Free Learning Ability as an Organizing Factor in the Evolution of Cognition

2013 ◽  
Vol 2013 ◽  
pp. 1-13 ◽  
Author(s):  
Solvi Arnold ◽  
Reiji Suzuki ◽  
Takaya Arita
Keyword(s):  
Selection Pressure ◽  
Learning Ability ◽  
Environmental Complexity ◽  
Baldwin Effect ◽  
Neural Structure ◽  
Neural Organization ◽  
Environmental Structure ◽  
Selection For ◽  
Efficient Learning ◽  
Complexity Thesis

This research explores the relation between environmental structure and neurocognitive structure. We hypothesize that selection pressure on abilities for efficient learning (especially in settings with limited or no reward information) translates into selection pressure on correspondence relations between neurocognitive and environmental structure, since such correspondence allows for simple changes in the environment to be handled with simple learning updates in neurocognitive structure. We present a model in which a simple form of reinforcement-free learning is evolved in neural networks using neuromodulation and analyze the effect this selection for learning ability has on the virtual species' neural organization. We find a higher degree of organization than in a control population evolved without learning ability and discuss the relation between the observed neural structure and the environmental structure. We discuss our findings in the context of the environmental complexity thesis, the Baldwin effect, and other interactions between adaptation processes.

scholarly journals Selection and niche trade-offs in biofilm-forming bacterial communities in experimental microcosms

2020 ◽  
Vol 2 (7A) ◽  
Author(s):  
Robyn Jerdan ◽  
Scott Cameron ◽  
Emily Donaldson ◽  
Andrew Spiers
Keyword(s):  
Biofilm Formation ◽  
Liquid Column ◽  
Significant Shift ◽  
Bet Hedging ◽  
Transfer Experiment ◽  
Serial Transfer ◽  
Fitness Advantage ◽  
Trade Offs ◽  
Selection For ◽  
Cell Densities

Static microcosms are a well-established system used to study the adaptive radiation of Pseudomonas fluorescens SBW25 and the adaptive biofilm-forming mutants known as the Wrinkly Spreaders (WS). We have developed this system to investigate selection within multi-species communities using a soil-wash inoculum dominated by biofilm-competent pseudomonads. Here we present community and isolate-level analyses of one serial-transfer experiment in which replicate populations were selected for over ten transfers and 60 days. Although no significant trends in improving community biofilm characteristics or total microcosm productivity were observed, a significant shift in biofilm-formation and microcosm growth by individual isolates recovered from the initial soil-wash inoculum and final transfers indicated that these communities were subject to selection for growth in these microcosms. Surprisingly, the fitness of the archetypal WS was poor when competing against community samples, and having compared the cell densities in the low-O2 region of liquid column below the biofilm, we suggest that part of the community’s fitness advantage comes from the ability to colonise this under-utilised niche as well as to compete at the A-L interface. Samples from the community biofilms and the low-O2 region were able to re-colonize both niches and many final transfer isolates grew throughout the liquid column as well as forming A-L interface biofilms. This suggests that there is a trade-off between fast growth under highly competitive conditions at the A-L interface and slower growth with less competition in the low-O2 region, with some isolates taking a bet-hedging approach a colonizing both niches in our microcosm system.

scholarly journals Phenotypic, genotypic and biochemical changes during pyrethroid resistance selection in Anopheles gambiae mosquitoes

2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Maxwell G. Machani ◽  
Eric Ochomo ◽  
Daibin Zhong ◽  
Guofa Zhou ◽  
Xiaoming Wang ◽  
...  
Keyword(s):  
Public Health ◽  
Insecticide Resistance ◽  
Anopheles Gambiae ◽  
Selection Pressure ◽  
Pyrethroid Resistance ◽  
Natural Populations ◽  
Biochemical Changes ◽  
Moderate Intensity ◽  
Agricultural System ◽  
Selection For

Abstract The directional selection for insecticide resistance due to indiscriminate use of insecticides in public health and agricultural system favors an increase in the frequency of insecticide-resistant alleles in the natural populations. Similarly, removal of selection pressure generally leads to decay in resistance. Past investigations on the emergence of insecticide resistance in mosquitoes mostly relied on field survey of resistance in vector populations that typically had a complex history of exposure to various public health and agricultural pest control insecticides in nature, and thus the effect of specific insecticides on rate of resistance emergency or resistance decay rate is not known. This study examined the phenotypic, genotypic, and biochemical changes that had occurred during the process of selection for pyrethroid resistance in Anopheles gambiae, the most important malaria vector in Africa. In parallel, we also examined these changes in resistant populations when there is no selection pressure applied. Through repeated deltamethrin selection in adult mosquitoes from a field population collected in western Kenya for 12 generations, we obtained three independent and highly pyrethroid-resistant An. gambiae populations. Three susceptible populations from the same parental population were generated by removing selection pressure. These two lines of mosquito populations differed significantly in monooxygenase and beta-esterase activities, but not in Vgsc gene mutation frequency, suggesting metabolic detoxification mechanism plays a major role in generating moderate-intensity resistance or high-intensity resistance. Pre-exposure to the synergist piperonyl butoxide restored the susceptibility to insecticide among the highly resistant mosquitoes, confirming the role of monooxygenases in pyrethroid resistance. The rate of resistance decay to become fully susceptible from moderate-intensity resistance took 15 generations, supporting at least 2-years interval is needed when the rotational use of insecticides with different modes of action is considered for resistance management.

scholarly journals Genomic selection for growth and wood quality in Eucalyptus: capturing the missing heritability and accelerating breeding for complex traits in forest trees

2012 ◽  
Vol 194 (1) ◽  
pp. 116-128 ◽  
Author(s):  
Marcos D. V. Resende ◽  
Márcio F. R. Resende ◽  
Carolina P. Sansaloni ◽  
Cesar D. Petroli ◽  
Alexandre A. Missiaggia ◽  
...  
Keyword(s):  
Genomic Selection ◽  
Complex Traits ◽  
Wood Quality ◽  
Forest Trees ◽  
Missing Heritability ◽  
Selection For

Positive association between resistance to Bacillus thuringiensis and overwintering survival of cabbage loopers, Trichoplusia ni (Lepidoptera: Noctuidae)

2008 ◽  
Vol 98 (3) ◽  
pp. 317-322 ◽  
Author(s):  
V. Caron ◽  
J.H. Myers
Keyword(s):  
Bacillus Thuringiensis ◽  
Trichoplusia Ni ◽  
Positive Association ◽  
Pest Species ◽  
Development Of Resistance ◽  
Trade Offs ◽  
Major Pest ◽  
Selection For ◽  
Overwintering Survival ◽  
Lepidoptera Noctuidae

AbstractDevelopment of resistance to insecticides has generally been associated with fitness costs that may be magnified under challenging conditions. Lepidopterans which are resistant to the biopesticide Bacillus thuringiensis subsp. kurstaki (Btk) have been shown to have reduced fitness, such as lower survival when subjected to overwintering stress. Recently, resistance to Btk has been found in some populations of Trichoplusia ni Hübner in greenhouses in British Columbia. This situation provides an opportunity to investigate potential trade-offs between overwintering survival and insecticide resistance in a major pest species. Here, we assess the survival and eventual fecundity of Btk resistant and susceptible T. ni pupae exposed to cool temperatures. Contrary to our expectations, resistant T. ni had higher overwintering survival than susceptible individuals. This is the first account of a potential advantage associated with Btk resistance. Resistant and susceptible moths had reduced fecundity and smaller progeny after cold exposure compared to controls, and this may counteract the survival advantage. Nevertheless, it seems unlikely that this is sufficient to select out the resistant phenotype in the presence of strong selection for resistance and in the absence of immigration of susceptible moths. The appearance of resistance without evidence of a trade-off in overwintering survival presents a major challenge to management in production greenhouses.

Selection for Simple and Complex Traits

2004 ◽  
pp. 373-389
Author(s):  
V. P. Gupta ◽  
G. S. Nanda ◽  
Darbeshwar Roy
Keyword(s):  
Complex Traits ◽  
Selection For

scholarly journals Can We Agree on What Robots Should be Allowed to Do? An Exercise in Rule Selection for Ethical Care Robots

2019 ◽  
Vol 12 (5) ◽  
pp. 1093-1102
Author(s):  
Dieter Vanderelst ◽  
Jurgen Willems
Keyword(s):  
Cost Effective ◽  
Training Data ◽  
Learning Approaches ◽  
Empirical Survey ◽  
Rule Selection ◽  
Control Rules ◽  
Care Robots ◽  
Trade Offs ◽  
Future Care ◽  
Selection For

AbstractFuture Care Robots (CRs) should be able to balance a patient’s, often conflicting, rights without ongoing supervision. Many of the trade-offs faced by such a robot will require a degree of moral judgment. Some progress has been made on methods to guarantee robots comply with a predefined set of ethical rules. In contrast, methods for selecting these rules are lacking. Approaches departing from existing philosophical frameworks, often do not result in implementable robotic control rules. Machine learning approaches are sensitive to biases in the training data and suffer from opacity. Here, we propose an alternative, empirical, survey-based approach to rule selection. We suggest this approach has several advantages, including transparency and legitimacy. The major challenge for this approach, however, is that a workable solution, or social compromise, has to be found: it must be possible to obtain a consistent and agreed-upon set of rules to govern robotic behavior. In this article, we present an exercise in rule selection for a hypothetical CR to assess the feasibility of our approach. We assume the role of robot developers using a survey to evaluate which robot behavior potential users deem appropriate in a practically relevant setting, i.e., patient non-compliance. We evaluate whether it is possible to find such behaviors through a consensus. Assessing a set of potential robot behaviors, we surveyed the acceptability of robot actions that potentially violate a patient’s autonomy or privacy. Our data support the empirical approach as a promising and cost-effective way to query ethical intuitions, allowing us to select behavior for the hypothetical CR.

scholarly journals Characteristics of survivors: growth and nutritional condition of early stages of the hake species Merluccius paradoxus and M. capensis in the southern Benguela ecosystem

2012 ◽  
Vol 69 (4) ◽  
pp. 553-562 ◽  
Author(s):  
Britta Grote ◽  
Werner Ekau ◽  
Erling K. Stenevik ◽  
Catriona Clemmesen ◽  
Hans M. Verheye ◽  
...  
Keyword(s):  
Selection Pressure ◽  
Larval Mortality ◽  
Larval Growth ◽  
Threshold Level ◽  
Nutritional Condition ◽  
Complex Relationship ◽  
Early Stages ◽  
Benguela Upwelling ◽  
Selection For ◽  
High Selection

Abstract Grote, B., Ekau, W., Stenevik, E. K., Clemmesen, C., Verheye, H. M., Lipinski, M. R., and Hagen, W. 2012. Characteristics of survivors: growth and nutritional condition of early stages of the hake species Merluccius paradoxus and M. capensis in the southern Benguela ecosystem. – ICES Journal of Marine Science, 69: 553–562. Larval mortality in marine fish is strongly linked to characteristic traits such as growth and condition, but the variability in these traits is poorly understood. We tried to identify the variability in growth in relation to conditions leading to greater survival chances for early stages of Cape hake, Merluccius paradoxus and M. capensis, in the Benguela upwelling ecosystem. During two cruises in 2007 and one cruise in 2008, hake larvae and juveniles were caught. Otolith microstructures revealed a larval age ranging from 2 to 29 days post-hatching (dph), whereas juvenile age was 67–152 dph. RNA:DNA ratios, used to evaluate nutritional condition, were above the relevant threshold level for growth. No strong coupling between growth and condition was detected, indicating a complex relationship between these factors in the southern Benguela ecosystem. Merluccius paradoxus juveniles caught in 2007 (the surviving larvae of 2006) had significantly higher larval growth rates than larvae hatched in 2007 and 2008, possibly indicating selection for fast growth in 2006. High selection pressure on growth could be linked to predation avoidance, including cannibalism.

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