scholarly journals Universal Evolutionary Model for Periodical Species

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Eric Goles ◽  
Ivan Slapničar ◽  
Marco A. Lardies
Keyword(s):  
Fitness Function ◽  
Evolutionary Model ◽  
Prime Numbers ◽  
Life Cycles ◽  
The Other ◽  
Exclusion Principle ◽  
Greatest Common Divisor ◽  
Predator Prey ◽  
Integer Multiple ◽  
New Period

Real-world examples of periodical species range from cicadas, whose life cycles are large prime numbers, like 13 or 17, to bamboos, whose periods are large multiples of small primes, like 40 or even 120. The periodicity is caused by interaction of species, be it a predator-prey relationship, symbiosis, commensalism, or competition exclusion principle. We propose a simple mathematical model, which explains and models all those principles, including listed extremal cases. This rather universal, qualitative model is based on the concept of a local fitness function, where a randomly chosen new period is selected if the value of the global fitness function of the species increases. Arithmetically speaking, the different interactions are related to only four principles: given a couple of integer periods either (1) their greatest common divisor is one, (2) one of the periods is prime, (3) both periods are equal, or (4) one period is an integer multiple of the other.

scholarly journals Study on evolution of a predator–prey model in a polluted environment

2021 ◽  
Vol 26 (6) ◽  
pp. 1052-1070
Author(s):  
Bing Liu ◽  
Xin Wang ◽  
Le Song ◽  
Jingna Liu
Keyword(s):  
Body Size ◽  
Function Analysis ◽  
Fitness Function ◽  
Rapid Evolution ◽  
Evolutionary Model ◽  
The Body ◽  
Predator Prey ◽  
Predator Prey Model ◽  
Prey Model

In this paper, we investigate the effects of pollution on the body size of prey about a predator–prey evolutionary model with a continuous phenotypic trait in a pulsed pollution discharge environment. Firstly, an eco-evolutionary predator–prey model incorporating the rapid evolution is formulated to investigate the effects of rapid evolution on the population density and the body size of prey by applying the quantitative trait evolutionary theory. The results show that rapid evolution can increase the density of prey and avoid population extinction, and with the worsening of pollution, the evolutionary traits becomes smaller gradually. Next, by employing the adaptive dynamic theory, a long-term evolutionary model is formulated to evaluate the effects of long-term evolution on the population dynamics and the effects of pollution on the body size of prey. The invasion fitness function is given, which reflects whether the mutant can invade successfully or not. Considering the trade-off between the intrinsic growth rate and the evolutionary trait, the critical function analysis method is used to investigate the dynamics of such slow evolutionary system. The results of theoretical analysis and numerical simulations conclude that pollution affects the evolutionary traits and evolutionary dynamics. The worsening of the pollution leads to a smaller body size of prey due to natural selection, while the opposite is more likely to generate evolutionary branching.

State of Fashion: Searching for the New Luxury

APRIA Journal ◽  
2020 ◽  
Vol 1 (1) ◽  
pp. 11-16
Author(s):  
José Teunissen
Keyword(s):  
Twentieth Century ◽  
Daily Life ◽  
Life Cycles ◽  
The Other ◽  
Century Model ◽  
Cocktail Party ◽  
The Public ◽  
Other Hand ◽  
The One

In the last few years, it has often been said that the current fashion system is outdated, still operating by a twentieth-century model that celebrates the individualism of the 'star designer'. In I- D, Sarah Mower recently stated that for the last twenty years, fashion has been at a cocktail party and has completely lost any connection with the public and daily life. On the one hand, designers and big brands experience the enormous pressure to produce new collections at an ever higher pace, leaving less room for reflection, contemplation, and innovation. On the other hand, there is the continuous race to produce at even lower costs and implement more rapid life cycles, resulting in disastrous consequences for society and the environment.

scholarly journals Competing Conventions with Costly Information Acquisition

Games ◽  
2021 ◽  
Vol 12 (3) ◽  
pp. 53
Author(s):  
Roberto Rozzi
Keyword(s):  
Information Acquisition ◽  
Evolutionary Model ◽  
Equilibrium Selection ◽  
The Other ◽  
Group Interactions ◽  
Social Coordination ◽  
Long Run ◽  
Stochastic Stability Analysis ◽  
The Stability ◽  
The Cost

We consider an evolutionary model of social coordination in a 2 × 2 game where two groups of players prefer to coordinate on different actions. Players can pay a cost to learn their opponent’s group: if they pay it, they can condition their actions concerning the groups. We assess the stability of outcomes in the long run using stochastic stability analysis. We find that three elements matter for the equilibrium selection: the group size, the strength of preferences, and the information’s cost. If the cost is too high, players never learn the group of their opponents in the long run. If one group is stronger in preferences for its favorite action than the other, or its size is sufficiently large compared to the other group, every player plays that group’s favorite action. If both groups are strong enough in preferences, or if none of the groups’ sizes is large enough, players play their favorite actions and miscoordinate in inter-group interactions. Lower levels of the cost favor coordination. Indeed, when the cost is low, in inside-group interactions, players always coordinate on their favorite action, while in inter-group interactions, they coordinate on the favorite action of the group that is stronger in preferences or large enough.

Speciation of cestoda. Evidence for two sibling species in the complex Bothrimonus nylandicus (Schneider 1902) (Cestoda: Cyathocephalidea)

Parasitology ◽  
1988 ◽  
Vol 97 (1) ◽  
pp. 139-147 ◽  
Author(s):  
F. Renaud ◽  
C. Gabrion
Keyword(s):  
Sibling Species ◽  
Definitive Host ◽  
Parasite Species ◽  
Adult Stage ◽  
Life Cycles ◽  
The Other ◽  
Congeneric Species ◽  
Biochemical Genetic ◽  
Autumn And Winter ◽  
Biological Differences

SUMMARYUsing biochemical genetic methods, we have distinguished 2 sibling species in the complex Bothrimonus nylandicus (Schneider, 1902), which infest 2 congeneric species of sole (Solea lascaris and Solea impar) on European coasts (Atlantic and Mediterranean). Neither of the parasite species is specific for either of the sole species, but one of them is present all year round, whereas the other is absent in the autumn and winter and only appears in the spring, subsequently disappearing at the end of the summer. Only S. impar lives in the Mediterranean, and is equally infested by both cestodes, whereas both species occur in the Atlantic and each of them is preferentially infested by 1 species of cestode. The shortness of the adult stage of the parasite in the definitive host and the presence of 2 life-cycles associated with competition between the 2 hosts in the Atlantic could be responsible for the biological differences observed and for maintaining the sibling species in sympatry.

Discrete Social Spider Algorithm for Solving Traveling Salesman Problem

2021 ◽  
pp. 2150020
Author(s):  
Asieh Khosravanian ◽  
Mohammad Rahmanimanesh ◽  
Parviz Keshavarzi
Keyword(s):  
Genetic Algorithm ◽  
Discrete Optimization ◽  
Heuristic Algorithms ◽  
Optimization Problems ◽  
Fitness Function ◽  
Traveling Salesman ◽  
The Other ◽  
Discrete Optimization Problem ◽  
Social Spider ◽  
Social Spider Algorithm

The Social Spider Algorithm (SSA) was introduced based on the information-sharing foraging strategy of spiders to solve the continuous optimization problems. SSA was shown to have better performance than the other state-of-the-art meta-heuristic algorithms in terms of best-achieved fitness values, scalability, reliability, and convergence speed. By preserving all strengths and outstanding performance of SSA, we propose a novel algorithm named Discrete Social Spider Algorithm (DSSA), for solving discrete optimization problems by making some modifications to the calculation of distance function, construction of follow position, the movement method, and the fitness function of the original SSA. DSSA is employed to solve the symmetric and asymmetric traveling salesman problems. To prove the effectiveness of DSSA, TSPLIB benchmarks are used, and the results have been compared to the results obtained by six different optimization methods: discrete bat algorithm (IBA), genetic algorithm (GA), an island-based distributed genetic algorithm (IDGA), evolutionary simulated annealing (ESA), discrete imperialist competitive algorithm (DICA) and a discrete firefly algorithm (DFA). The simulation results demonstrate that DSSA outperforms the other techniques. The experimental results show that our method is better than other evolutionary algorithms for solving the TSP problems. DSSA can also be used for any other discrete optimization problem, such as routing problems.

Predator and prey detection in two species of water bear (Tardigrada)

2019 ◽  
Vol 188 (3) ◽  
pp. 860-864 ◽  
Author(s):  
Harry A Meyer ◽  
Hannah E Larsen ◽  
Nézira O Akobi ◽  
Garret Broussard
Keyword(s):  
Environmental Conditions ◽  
The Other ◽  
Physical Contact ◽  
Nutrient Agar ◽  
Control Treatment ◽  
Prey Detection ◽  
Potential Prey ◽  
Predator Prey ◽  
Petri Dishes

Abstract Tardigrade behavioural studies have focused on responses to abiotic environmental conditions. Predator–prey interactions have received some attention, but not how predators and prey might detect one another. Here, we investigate whether a predatory tardigrade species is attracted to, and a potential prey tardigrade avoids, areas previously occupied by the other. In our experiments, Milnesium lagniappe was the predator and Macrobiotus acadianus the prey. Petri dishes with non-nutrient agar were used as experimental arenas. In one treatment, we allowed Macrobiotus to roam over half of the agar for 20 h, while leaving the other half free of Macrobiotus. We then removed the prey and introduced the predator. In the control treatment, no prey were added. Results indicated that Milnesium individuals were significantly concentrated in the area previously occupied by Macrobiotus, whereas no such concentration was evident when Macrobiotus had not been present. A similar protocol was used to test whether Macrobiotus avoided areas previously occupied by the predator. As expected, Macrobiotus were significantly concentrated in the area never occupied by Milnesium, unlike the control treatment. These results suggest that both species can detect the other without physical contact and react accordingly. Given that the experiments were conducted in darkness, detection is probably olfactory.

Dormant plasticity of rotifer diapausing eggs in response to predator kairomones

2021 ◽  
Vol 17 (11) ◽  
Author(s):  
Xuwang Yin ◽  
Yuecen Zhao ◽  
Shuang Tian ◽  
Xiaochun Li
Keyword(s):  
Life Cycles ◽  
Freshwater Ecosystems ◽  
Sexual Life ◽  
Hatching Rate ◽  
Ecological Implication ◽  
Maternal Environment ◽  
Predator Prey ◽  
Diapausing Eggs ◽  
Embryonic Exposure ◽  
Phenotypic Responses

In freshwater ecosystems, hatching strategy of diapausing eggs (DEs) under predation risk has important ecological implication for zooplankters. Although kairomones released by predators can induce phenotypic responses of prey, hatching patterns of DEs in response to kairomones have received contradictory conclusions in zooplankters. Maternal environment may also affect hatching strategy of DEs during predator–prey interactions. We used classical Brachionus calyciflorus – Asplanchna models to determine the timing and proportion of DE hatching in association with parental and embryonic exposure to kairomones. Results obtained from two Brachionus clones supported the hypothesis that DEs could detect Asplanchna kairomones and adjust hatching patterns. DEs showed early and synchronous hatching patterns in the environment with kairomones. Data also supported the prediction that DEs could gain information about predators from maternal environments and adjusted their hatching pattern in response to the presence of kairomones. Compared with DEs from Brachionus mothers not exposed to kairomones, DEs produced by mothers that were experienced with kairomones attained a higher hatching rate when both of them hatched in the environment either with or without kairomones. Our results suggest that DEs of B . calyciflorus possess dormant plasticity to defend against predation from Asplanchna , which may be regulated by maternal environmental effects during sexual life cycles.

Interaction of ecology, taxonomy and distribution in some Mesembryanthemaceae

Bothalia ◽  
1983 ◽  
Vol 14 (3/4) ◽  
pp. 653-659 ◽  
Author(s):  
H. E. K. Hartmann
Keyword(s):  
Plant Communities ◽  
Life Cycles ◽  
The Other ◽  
Distribution Data ◽  
Precipitation Data ◽  
Strong Correlations ◽  
Growth Forms ◽  
Structural Pattern ◽  
Arid Conditions ◽  
The Family

Many taxa of the family Mesembryanthemaceae show close correlations between distribution and environmental factors, e.g. occurrence on limestone or quartzite only, but few cases have been studied in detail. Recent investigations in anatomy, morphology, life cycles, physiology, and in energetic properties indicate that fundamentally different patterns are developed in adaptation to arid conditions, even in reaction to identical edaphic and climatic factors.On the other hand, little is known about the immediate influence of changes in the natural environment. Studies in populations of the subgenus Cephalophyllum of the genus  Cephalophyllum N.E. Br. show strong correlations between precipitation data and habit, which can superimpose genetic dispositions. In addition, growth forms are well adapted to certain types of plant communities, so that superficially, a diffuse structural pattern results.Long term studies, in the field and in the greenhouse, of growth forms in relation to time, to precipitation, and to associations, allow first suggestions for adaptive pathways in the evolution of the group, and the results form a basis for taxonomic decisions in this highly confused taxon. Finally, the example offers aspects for the better understanding of interaction between ecology and distribution data.

Cropping system effects on giant foxtail (Setaria faberi) demography: I. Green manure and tillage timing

Weed Science ◽  
2003 ◽  
Vol 51 (6) ◽  
pp. 919-929 ◽  
Author(s):  
Adam S. Davis ◽  
Matt Liebman
Keyword(s):  
Seed Predation ◽  
Weed Management ◽  
Green Manure ◽  
Seedling Emergence ◽  
Cropping System ◽  
Red Clover ◽  
Life Cycles ◽  
The Other ◽  
Giant Foxtail ◽  
Crop Sequence

Manipulation of cropping systems to improve weed management requires a better understanding of how crop- and soil-related factors affect weed life cycles. Our objective was to assess the impacts of timing of primary tillage and use of legume green manure on giant foxtail demography and soil properties. We measured giant foxtail seed survival and dormancy, seedling emergence and survival, and fecundity, in addition to soil phytotoxicity, chemical properties affecting soil fertility and soil water, in the transition between the wheat and corn phases of a wheat–corn–soybean crop sequence. Postdispersal predation of giant foxtail seeds was measured in all three phases of the crop sequence. Wheat was grown either as a sole crop (W) or underseeded with red clover (R), and residues from this phase were rototilled either in the fall (FT) or in spring (ST). There were strong interactions between Red clover and Tillage timing in their effects on giant foxtail recruitment and fecundity in corn. Giant foxtail seedling emergence was 30% lower, and time to 50% emergence was more than 1 wk later, in the ST/R treatment than in the ST/W, FT/W, and FT/R treatments, which did not differ. However, fecundity of giant foxtail was 200% greater in the ST/R treatment than in the other three treatments because of suppressed early corn growth. The net effect of the ST/R treatment on giant foxtail demography in corn was to greatly increase inputs to the seedbank compared with the ST/W, FT/W, and FT/R treatments. Giant foxtail demography in the wheat phase was also affected by Red clover. There was a 200% increase in daily rates of postdispersal seed predation in the wheat phase of the R treatment compared with the W treatment. High-seed predation in the wheat phase and low fecundity in the corn phase of the FT/R treatment suggest that population growth rate of giant foxtail will be lower in this treatment than in the other treatments. The degree of soil phytotoxicity from red clover residues, the changes in the amount of interference from the corn crop early in the growing season, and the differential suitability of crop residues in the different rotations as habitat for seed predators all contributed to changes in giant foxtail demography. Understanding the effects of cropping system characteristics on entire weed life cycles will facilitate the design of integrated suites of complementary weed management tactics.

scholarly journals A New Species of Ligyrocoris Stal With a Key to the Northeastern Species (Hemiptera:Lygaeidae)

1963 ◽  
Vol 70 (1) ◽  
pp. 17-21
Author(s):  
Merrill H. Sweet
Keyword(s):  
New Species ◽  
Life Cycle ◽  
New England ◽  
Related Species ◽  
Habitat Preferences ◽  
Life Cycles ◽  
The Other ◽  
Closely Related Species ◽  
Carex Stricta ◽  
A New Species

In the course of current work upon the biology and ecology of the Rhyparochrominae of New England, a new species of Ligyrocoris was discovered. The species runs in Barber's (1921) key to the couplet separating diffusus (Uhler) from sylvestris (L.), but is distinct from either species. While the new species is closely related to these species, it is also quite close to L. depictus which is separated out in a different part of Barber's key.These four closely related species are sympatric in New England, although they are markedly different in their overall distribution. The habitat preferences and life cycles of the species are quite different (Sweet, unpublished). The habitat of the new species described below is most unusual for the genus. The greater part of the type series was collected along the margin of a small pond where sedge clumps were standing in the water among occasional exposed rocks rather than in relatively dry fields or slope habitats where the other species occur. The species feeds upon the seeds of the sedge, Carex stricta Lam, and its life cycle is apparently adapted to that of the sedge, which fruits in late May and June. The insect becomes adult in mid-June and lays eggs until mid-July. The eggs remain in diapause over the summer and winter and hatch in May.

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