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''The Evolutionary Theory of Sex'' is a is easier without a species having Sex added as a complication, so if reproduction is not the point of sex then what is? What evolutionary advantage explains the widespread including of this complication to the reproductive process? This hypothesis suggests that the answer lies in chromosome based Sex-determination System s that allow a degree of independent evolution of the sexes. For example, human females lack a Y Chromosome so evolution of the Y chromosome can test variations without polluting the human Genome . This hypothesis hopes to explain many sex-related phenomena such as Sexual Dimorphism , Sex Chromosomes ,Geodakyan V. A. (2000). Evolutionary Chromosomes And Evolutionary Sex Dimorphism. “Biology Bulletin” 27 N 2, 99–113. asymmetry of brain Geodakyan V. A. (1992). Evolutionary Logic of the Functional Asymmetry of the Brain. “Doklady Biological Sciences” '''324''' N 1-6, 283–287. and hands, Geodakyan V. A., Geodakyan K. V. (1997). A New Concept on Lefthandedness. “Doklady Biological Sciences” '''356''' N 1-6, 450–454. Reciprocal Effects , and Congenital Heart Defects . Geodakyan V. A., Sherman A. L. (1971). Svjaz' vrozdennych anomalij razvitija s polom (Relation of birth defects with sex). “Zh. Obsh. Biol.” '''32''' N 4, 417–424. The hypothesis includes the concepts of the Principle of Conjugated Subsystems and Asynchronous Evolution. The Fitness Landscape of a Species is thought to be evaluated at nearby points by one sex resulting in greater and greater perfection at traits known to be advantageous; while the other sex specializes in evaluating (by reproducing or not) less nearby points in the fitness landscape through more untested genetic variations. (See Nelder-Mead Method for a computer algorithm that illustrates searching a Fitness Landscape ; some variations of which first search far points (male-like evolution) then decrease the distance of the search (females-like evolution).) The terminology of the Algorithm ic theory identifies the two sexes' evolutionary strategies or algorithms as "subsystems" and refers to the male sex's evolutionary algorithm as the "Operative Subsystem" and the female sex's evolutionary algorithm as the "Conservative Subsystem". The operative subsystem starts the change, verifies and selects the useful traits and then passes them to conservative subsystem to refine them thus creating a Division Of Labour . New information from the Environment is first incorporated into male only genes, and then after many generations gets transferred to females (e.g. Transposon ), so the evolution of males precedes the evolution of females; while the perfection of traits remains a female domain. This time shift (two phases of a Trait’s evolution) creates two forms of a trait (male and female)— Sexual Dimorphism for the population. The hypothesis was included in two psychology textbooks, Vasiltshenko G. S. (1977, 2005) General sexopathology. Moscow, Medicine 488 p. Nartova-Boschaver S. K. (2003) Differential psychology: Textbook. Moscow. Flinta Moscow psychological-social institute. a college study program, Moscow Institute of Physics and Technology. Department of Molecular and Biological Physics. Lectures for the 1st grade “Biology basics”. Lecture #24 Evolutionary Theory of Sex. Biotechnology. Immunology. Signal transmission in the body. http://www.fizhim.ru/student/files/biology/biolections/lection24/ Kharkov national university (Ukraine). Faculty of psychology. Department of general psychology. Cycle of lectures “Gender studies in psychology” Lecture #11. Studies of gender differences in brain organization and cognition. http://www.gender.univer.kharkov.ua/speckursy-025.shtml and was covered in Russian newspaper and magazine articles, Bibliography two articles in a monthly Russian-language local newspaper published by a US travel agency, Rahlis L. (1998) Why God created Adam and Eve? Russia House (Atlanta, GA), September N 9 (68), 4. Rahlis L. (1999) Supplementing each other. Russia House (Atlanta, GA), February N 2 (73) 5. and Russian TV programs. Gordon A. (2002) Evolutionary theory of sex. “Program «00:30»” NTV, June 06. Gordon A. (2002) Evolutionary theory of sex-2. “Program «00:30»” NTV, Apr 15. Gordon A. (2003) Theory of brain asymmetry. “Program «00:30»” NTV, Dec 09. However, not all of these ideas are widely-known or accepted, and remain almost unknown outside of Russia.[http://arxiv.org/PS_cache/cs/pdf/0408/0408006v1.pdf Translation of Vigen A. Geodakian, ''Why Two Sexes?'' arXiv.org 1 August 2004 SYSTEMS MODELING The "International Society for the Systems Sciences"'s Bela Banathy states: :"By OBSERVING various types of systems and studying their behavior, we can recognize characteristics that are common to all systems. Once we have identified and described a set of concepts that are common to the systems, and observed and discovered among some of them certain relationships, we can construct from them general systems PRINCIPLES. Thus, a systems principles emerges from an interaction/integration of related concepts. Next we are in the position to look for interrelations among principles and organize related principles in to certain conceptual schemes we call SYSTEMS MODELS. This process of starting from OBSERVATION and arriving at the CONSTRUCTION of systems models constitutes the first stage of developing a systems view." International Society for the Systems Sciences article ''A TASTE OF SYSTEMICS'' By Bela Banathy V. Geodakian's "Principle of Conjugated Subsystems" is an example of this. PRINCIPLE OF CONJUGATED SUBSYSTEMS The Principle of Conjugated Subsystems introduced by V. Geodakian states that: :Any System adapting to a variable environment divides into two conjugated subsystems, specialized according to conservative and operative trends of Evolution , which increases the system stability as a whole. Geodakian V. A. (1972) O strukture evoljucionirujuscich sistem (On the structure of evolving systems) “Problemy Kibernetiki,” 25 81-91 Moscow, “Nauka”. The Principle of Asynchronous Evolution The idea of evolution implies two main and to some extent alternative aspects: conservation and variation. For better realization of the first aspect - conservation, the system ought to be steady, stable, and unchangeable (inert), i.e. to be if possible "farther" (in the informational terms) from destructive factors of the environment. But these factors simultaneously carry on useful information about changes in environment. And if the system has to get adapted to the latter, to be changed in accordance with the environmental alterations (the second aspect of evolution) it must be sensitive, labile and variable, i.e. to be as far as possible, "closer" (again in information terms) to harmful factors of the environment. Consequently the same idea of evolution raises conflicting requirements for the system: to be simultaneously "farther" from and "closer" to the environment. The first possible solution: the system should be at some optimal "distance" from the environment. The second one: the system should differentiate into two conjugated subsystems, one of them to be removed “farther” from the environment for preserving the accumulated information, and another one to be drawn “nearer” to the environment for receiving new information. The second solution overcomes the conflict to some extent and increases the stability of the system as a whole. ASYNCHRONOUS EVOLUTION V. Geodakian claims that: :"All biological theories especially classical genetics and Darwinism silently assume the idea of synchronous evolution. This approach is suitable for the description of evolution of unitary systems. However, these theories can not explain behavior of binary systems same as you can not solve three-dimensional problem within a plane. Binary systems have two subsystems (or forms) of relatively homogeneous elements. In the case of [a population they are male and female sexes. [... The subsystems change at a different speed. o perative subsystem starts the change, verifies and selects the useful traits and then passes them to conservative subsystem. This delay creates a difference between the two subsystems both in morphological (dimorphism) and time (dichronism) aspects." Conservation and variation are the main aspects of the system evolution. For monomodal (unitary) systems ( Asexual , symmetric) they are alternative. (e.g. Bacteria Phenotypic Plasticity ) The more the system changes, the less it gets preserved. The division of the system into two related subsystems (one specialized in conservative aspects and the other specialized in operative aspects of evolution) allow improving both aspects at the same time. This solution contributes to the system stability as a whole. The evolution of the system occurs asynchronously in such a way that the operative subsystem changes first and the conservative one—follows later. Useful traits are verified and selected in the operative subsystem and only after some time gets transferred into conservative one. ANALYSIS OF A SEX RIDDLE )]] The sex notion consists of two fundamental phenomena: the sexual process (conjugation of genetic information of two persons) and the sexual differentiation (partitioning this information into two parts). Depending on the presence (+) or absence (-) of these phenomena, the whole variety of existing reproduction models can be divided into three basic forms: asexual (-, -), hermaphrodite (+, -), and bi-sexual reproduction (+, +). The sexual process and sexual differentiation are distinct, and moreover, directly opposite phenomena. Indeed, the sexual process diversifies genotypes, which is its objective in evolution, whereas differentiation halves the resulting diversity. For instance, in an asexual population of size N, the maximum theoretically possible variability of offspring genotypes is N, given that the genotypes of all parents are different. Since the offspring of each asexual individual is a clone with the same genotype, the variability of the offspring σ is always lower than N. In the sexual process, the variability of offspring is squared. In hermaphroditic organisms, each of N individuals can mate with all individuals except itself, i.e., N - 1; but, as the cross of individual A with individual B is the same as that of individual B with individual A (there is no reciprocal effect), at N >> 1 , σ = N(N - 1)/2 ≈ N2/2; with the reciprocal effect, σ = N2. In dioecious forms, sex differentiation that excludes same sex combinations (male-male, female-female), decreases the amount of diversity possible in hermaphrodites by at least two times: σ = N/2 x N/2 = N2/4 (each female with each male, with the same number of males and females equal to N/2). The offspring diversity in a population of dioecious organisms also depends on the Sex Ratio in the parental generation: it is the highest at a 1:1 sex ratio and decreases with any deviation from it. The maximum progeny diversity of the asexual, hermaphrodite, and bi-sexual populations of the same size N are related as N : N2/2 : N2/4, i.e., the diversity is at least halved while passing from hermaphrodite to bisexual reproduction! Then, it becomes completely unclear what the differentiation is intended for, if it halves the main bonus provided by the sexual process. Why are all progressive species bi-sexual, since the asexual process is much more efficient and simple, and hermaphrodites produce a more diversified progeny? This is the essence of the sex puzzle. The fact that this problem is still unsolved is primarily due to the lack of a clear understanding that the sexual process and sexual differentiation are opposite phenomena. Researchers make attempts at understanding the advantage of the sexual reproduction (hermaphrodite and bi-sexual forms) over the asexual one, although it is necessary to understand the advantage of bi-sexuals over hermaphrodites. The purpose of the sexual process is clear, and consists of diversifying. It is needed to comprehend the objective of the sexual differentiation. Although it is recognized that, because bi-sexual methods have no visible advantages over asexual ones, bi-sexual reproduction should provide us with significant evolutionary bonuses, the sex problem is commonly considered as a reproduction problem but not an evolutionary one. SPECIALIZATION OF SEXES Sex differentiation is specialization in preserving and changing the genetic information of population. One of the sexes should be informationally more closely connected with the environment, and be more sensitive to the environmental factors. Higher mortality and vulnerability of the males to all harmful factors of the environment make one believe that it is the operative, ecological subsystem of the population. While the females are the conservative subsystem that preserves the existing genotype distribution in the population. A series of mechanisms were developed during different stages of sex evolution to provide this specialization. Compared to females, males experience more mutations, inherit fewer properties of their parents, have narrower reaction norm, higher aggressiveness and inquisitiveness, riskier behavior and other properties that move them closer to the environment. All these properties, moving the male sex to the frontline of the evolution, provide for receiving of ecological information. The second group of properties includes great superfluity of male gametes, their small size and high mobility, the greater activity of mobility of males, their inclination towards polygamy and other ethologic and psychological qualities. Long periods of pregnancy, feeding and taking care of the descendants among the female population in reality increases the efficient concentration of the males, turning the male sex into superfluous, and thus cheap, while the female sex is turned into deficit and thus more expensive. As a result of conservative-operative specialization of sexes, asynchronous evolution takes place: new traits first appear in the operative subsystem (males), are tested there, and then are passed on to the conservative subsystem (females). ENVIRONMENTAL INFORMATION First, change of factors of environment can eliminate most sensitive to the given factor part of individuals, as a result of Natural Selection . Second, environmental changes create discomfort conditions. As a result other part of a population can be partially or completely discharged from duplication, due to sexual selection. Third, the changed environment modifies survived part of a population, creating morpho-physiological, behavioral and other non inherited adaptations, due to a Norm Of Reaction . Two processes (elimination and discrimination) remove some genotypes from a reproduction pool while a third (modification) allows some genotypes to survive. To receive the ecological information from the environment males should have a greater phenotypic variation which can be a consequence of their wider genetic variation. It can also reflect wider reaction norm of females which allows them to leave zones of elimination and elimination discomfort. Wider genetic variation of males can be due to their higher mutation rate. More additive inheritance of parental traits by female offspring can decrease their variation compare to males. There are two mechanisms that control Population Parameter s in animals – Stress and Sex Hormones . The plants receive ecological information through the amount of Pollen . Geodakyan V. A. (1977). The Amount of Pollen as a Regulator of Evolutionary Plasticity of Cross-Pollinating Plants. “Doklady Biological Sciences” 234 N 1-6, 193–196. It seems that particular nature of the environmental factor which causes the discomfort of the organism has no significance for starting up these mechanisms. The cause of the discomfort (frost, dry periods, famine or enemies) makes no difference. The generalized ecological information has one dimension only (good or bad) and its cause is unimportant. WIDER REACTION NORM OF FEMALES Wider Reaction Norm of females was theoretically predicted in 1973. Geodakyan V. A. (1973). Differential Sex Mortality and Reaction Norm. “Biol. Zh. Arm.” 26 N 6, 3–12. Geodakian V. A. (1974). Differential Mortality and Reaction Norm of Males and Females. Ontogenetic and Phylogenetic Plasticity (russ) “Zh. Obshch. Biol.” '''35''' N 3, 376-385. It means that in males the share of "hereditary component" must be larger and of the "environmental one" smaller than in females. Therefore in males the phenotypical distribution in population better reflects the genetic distribution. In females the environmental influence in ontogenesis is stronger, therefore any ontogenetic shift, any "education" or "training" is more efficient. If the hypothesis is valid, the differences between monozygous female twins must be greater than between the male ones. At the same time in dizigous twins like in common siblings, everything must be vice versa. Two studies conducted on 44 monozygous pairs Vandenberg S. G., McKusick V. A., McKusick A. B. (1962). Twin data in support of the Lyon hypothesis. “Nature”. 194 N 4827 505–506. and 53 monozygous and 38 dizigous pairs of twins Chovanova E., Bergman P., Stukovsky K. (1980) Abstracts of communications of II Congress of European Anthropological Association, Brno, 136. confirmed the predictions. Much direct and indirect evidence can be presented in favor of the hypothesis. For example, greater conformism of females well known to psychologists has not been adequately interpreted up till now. Harper E. B., e.a. (1965). Young children's yielding to false adult judgment. “Child. Development”. 36 175–183. McCoby E.E. (1966). The Development of Sex Differences, Stanford, Stanford Univ. Press. Kon I.S. (1967). Sociology of Personality, Moscow, "Politizdat". ONTOGENETIC PLASTICITY The wide reaction norm makes females more flexible in ontogenesis (adaptive). It enables the females to leave elimination and discomfort zones and to be gathered in the comfort zone around the population norm. It narrows the phenotypical dispersion of females and decreases their mortality. Contrary, the narrow reaction norm of males makes them less flexible in ontogenesis, does not permit the phenotypical dispersion to be narrowed, i.e. to leave the elimination and discomfort zones. Greater phenotypic variation of male sex makes it more sensitive to the environment and increases its damageability and mortality. Slightly exaggerating, it is possible to tell, that informational relationship of a population with the environment is based upon the elimination of males and the education (ontogenetic shift) of females. HIGHER MORTALITY OF MALES In a course of ontogenesis the sex ratio for many species of plants, animals and humans goes down. It is related to the raised death rate and damageability of male’s systems in comparison with female ones at almost all ontogenesis stages and at all levels of organization. Whether we study various species (the humans, animals or plants), different levels of the organization (an individual, organ, tissue or a cell) or stability to different harmful factors of environment (low and high temperature, starvation, poisons, parasites, diseases, etc.)—anywhere the same picture is observed: the raised death rate or damageability of male’s systems in comparison with corresponding female’s. Hamilton (1948) reviewed differential gender death rate for 70 species, including such various forms of a life, as nematodes, mollusks, crustaceans, insects, arachnoidea, birds, reptiles, fishes and mammals. According to these data, for 62 species (89%) average life of males is shorter, than females; for the majority of the remaining 11% there is no difference, and only on occasion males live longer, than females. Hamilton J. B. (1948). The role of testicular secretions as indicated by the effects of castration in man and by studies of pathological conditions and the short life span associated with maleness. “Recent Progress in Hormone Research” 3 N.Y., Acad. Press, 257–322. Higher mortality of males is one of the puzzles of sexuality, a general biological phenomenon, which no theory could explain satisfactorily. In new theory it is interpreted as a payment for new ecological information, as a useful form for population to get new information from the environment. For example males have higher susceptibility to all new diseases of our century (infarction, arteriosclerosis, cancer, schizophrenia and others). REVERSIBILITY OF MALES Under extreme conditions, as a rule, more males are extinct and simultaneously more males are required for selection. Both males’ mortality and males’ birth-rate increase imply reversibility of males increase. In 1965 it was proposed that besides the direct relation, there exists a Negative Feedback between secondary and tertiary Sex Ratio The feedback is represented in cross pollinating plants by the amount of pollen caught on the female flower and in animals by the intensity of sexual activity expressed via unequal aging of X- and Y-sperms and different affinity of the fresh and aged eggs to these latter. The small amount of pollen, intensive sexual activity of males, fresh sperm and aged eggs are factors leading to increase in the number of males. Geodakyan V. A. (1977). The Amount of Pollen as a Regulator of Evolutionary Plasticity of Cross-Pollinating Plants. “Doklady Biological Sciences” 234 N 1-6, 193–196. Geodakyan V. A. Geodakyan S.V. (1985). Is there a negative feedback in sex determination? “Zurnal obschej biol.” '''46''' N 2 201-216. INFORMATION TRANSFER Father and mother transfer each to descendant approximately identical amount of the genetic information, but the quantity of progeny that males can produce is much more compared to female. One male basically can transfer the information to the entire generation of a population. The females can not do that. In a strictly monogamous population the number mothers and fathers is equal. Contrary, in a panmictic or polygamous population the number of mothers is always greater than the number of fathers. It means that the old hereditary information concerning the distribution of genotypes in panmictic population is better, more completely and representatively transmitted by the females. Whereas a wide communication channel between males and their progeny makes possible better transmission of new information to the offspring. By leaving more offspring rare male organisms can multiply their ecologically valuable genotypes. So, in changing environment, different reaction norm and channel to the progeny create genotypic sexual dimorphism in the first generation Is this "new" information gets leveled at fertilization or gets preserved? The existence of the reciprocal effects suggest that genetic mechanisms exist that prevent complete mixing of all genetic information. This is accomplished via Y Chromosome which is transferred from father to son. Geodakian V. A. (2000). Evolutionary Chromosomes And Evolutionary Sex Dimorphism. “Biology Bulletin” 27 N 2, 99–113. SEE ALSO )]] REFERENCES EXTERNAL LINKS
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