Variation and selection in the MM21 origami bird

Variation and Selection in the MM21 Origami Bird

Background
The Hardy-Weinberg principle states that gene frequencies in a population remain constant while the genotype frequency of a population becomes the first generation of random mating. However, this situation is not obeyed and both gene frequencies and genotype frequencies are subjected to change under the effects of mutation, natural selection, reproductive fitness and random drift in individuals of a population (Turchin, 2001). Natural selection occurs at individual levels when such individuals develop certain adaptive traits that help them to combat environmental conditions or predations. Individuals failing in acquiring these adaptive traits will perish, according to the theory of Darwin: Survival of the fittest, because he postulated nature selects only those individuals that are suitable to thrive over others. This leads to the evolution of a given species where the characters of an offspring markedly differ that from a parental prototype (Tompkins et al., 2003).
The present article reflects the effects of a simulation experiment on a fictional bird Avis papyrus. The bird is hypothetically assumed to fly long distances for laying eggs at a place called Minato Mirai. The experiment postulates only the birds that are suitable to fly long distances will be capable of producing eggs. Thus an individual might become suitable to acquire certain traits that may not confine them to their natural habitats, for example the natural habitat of Avis papyrus is Yokohama springs as this habitat bears the food and drinks of this indigenous bird.

Experimental Protocol
The experiment was a simulation experiment, and it was designed in such a way so as to evaluate the effects of genetic variation and natural selection on them. This will help to estimate the evolutionary trends that occur in these birds to make them fittest to fly and survive t different environmental conditions. The hypothesis considered in the experiment was these birds are reproducing asexually, to eliminate the chances of speculating bias in different gender’s fitness and survival. Hence, the experimentation will at least prove the suitability and fitness of a particular individual under different simulation conditions.
Methodology
Artificial birds were constructed through paper and pipes, which formed the wings and axis of the body of the bird. Alterations were induced in wing circumference, wing width and position of the front and distance wings in subsequent generations through random manipulations. To eliminate the chances of bias a coin and a die was tossed, to induce the morphological changes from one generation to another generation. The statistical hypothesis was based on the evaluation of correlation coefficient. This means a distance of flying may be related positively to adaptive traits or negatively with adaptive traits. The correlation coefficient has a value from +1 to -1 and includes 0. 0 indicates that there is no correlation whereas +1/-1 values indicate positive or negative correlation. A two-tailed t-test was done to evaluate the significance of correlation coefficient. If the p-value is more than 0.05, it will be postulated that flying distance is not related to adaptive traits of change in wing circumference, wing width and position of wings and any observation has happened due to chance factors of random sampling. While if the value is less than 0.05 then it will be postulated that flying distance is related to adaptive traits of change in wing circumference, wing width and position of wings and any observation has not happened due to chance factors of random sampling, but due to natural selection pressures.
Results
The area of the wings was first extrapolated from the area of the rectangular strips of paper of 2 * 20 cm= 40-centimetre square. From area, the radius of the wings was found to be 3.55cm. Thus, the parent bird has wing circumference as 22.294 cm and wing width as 7.10 cm. Measurements are done for two generations, and the 1st number indicates the parental bird from which the asexual reproduction started. The other individuals were derived from the measurement criteria of dice and coin; lethal mutations were eliminated when the circumference of the wings was lower than the circumference.
Generation
(coloured)
Numbers are individual birds
Front Wing to head Rear Wing to tail Circumference of front wing Circumference of rear wing Width of rear wing Circumference of straw Average distance flew
1 3 3 22.294 22.294 7.1 16 102
2 3 3 22.294 22.294 7.1 16 103
3 4 4 24.294 24.294 7.3 16 104.5
4 2 2 26.294 24.294 6.8 16 108.4
5 4 2 28.29 24.29 7.1 16 107
6 2 4 24.29 20.29 6.8 16 88
7 1 1 20.29 26.29 7.9 16 76

Fig 1: represents the relation of the distance of front wing to head with a distance of the flight. The correlation coefficient was 0.75 with a p value <0.05. This indicates that more the distance of front wing to head more is the distance of the flight.

Fig 2: represents the relation of the distance of rear wing to tail with a distance of the flight. The correlation coefficient was 0.27 with a p-value >0.05. This indicates that more the distance of rear wing to tail more is the distance of the flight, but the results are not statistically significant.

Fig 3: represents the relation of the circumference of front wing to a distance of the flight. The correlation coefficient was 0.66 with a p value <0.05. This indicates that more the circumference more is the distance of the flight.

Fig 4: represents the relation of the distance of flight with a circumference of a rear wing. The correlation coefficient was -0.13 with a p value <0.05. This indicates that more the circumference of rear wingless is the distance of the flight.

Fig 5: represents the relation of the distance of flight with a width of the rear wing. The correlation coefficient was -0.61 with a p value <0.05. This indicates that more the wing width less is the distance of the flight.
Discussion and Conclusion
The most successful bird that had greater distance of flight was the one which should have more circumference of the front wing compared to rear wing, lesser rear wing width and more the distance of front wing from the head. The most successful bird was bird number 4, and interestingly circumference of the front wing is the predominant determining factor than a distance of front wing from head or wing width. Natural selection occurs at the level of selective pressure on a circumference of front wings as this is the most successful adaptive trait that helps the birds to fly long distances.
References
Turchin, P. & Batzli, G.O. (2001) Availability of food and the population
dynamics of arvicoline rodents. Ecology, 82, 1521–1534.
Tompkins, D.M., White, A.R., Boots, M. (2003) Ecological replacement
of native red squirrels by invasive greys driven by disease.
Ecology Letters, 6, 189–196