Aristotle Biology
Georgia Vasilikou Vasiliki Karagouni Efrosini Koemtzopoulou 1st Experimental High School of Thessaloniki Class: Α1 Supervisors: mrs Achilleos Claire, mr Papadopoulos Stavros
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Contents
Introduction Biography of Aristotle The biological work Aristotle today Conclusion Bibliography
INTRODUCTION As part of the 1st class' research work during this school year, our team worked on Aristotle. Specifically, we studied a number of works referring to natural history, known as biological Aristotle. This series consists of several books of undeniable evidence of which the first, "History of animals", is a recording of Aristotle's facts and observations and the rest of them are theories / principles he formulated based on these facts and observations [1].
BIOGRAPHY Aristotle was born in 384 BC and grew up in Stagira. He was very interested in biology and anatomy because some of his family members were doctors. In 367 BC, Proxenos, who was his guardian after his parents' death, sent Aristotle to study at Plato's Academy in Athens. He stayed there until the age of 37. He was closely associated with his teacher and some of the other students, like Xenocrates, and Eudoxus. He was very smart, eager to learn and diligent. [2] Plato called him ''the reader'' and ''the mind of the academy''. It is clear that the Platonic philosophy had a great influence both in his life and in his work [1]
Image 1: Aristotle discusses with Plato in the Academy
After Plato's death in 347 BC, when Spefsipos became the headmaster of the academy, Aristotle and Xenocrates went to Assos, where they taught in the philosophical school for three years. Afterwards, he moved and taught in Lesvos until 342 BC. He was married then with the biologist named Pythiada. With her he had a daughter and after the death of his first wife, he married Erpyllida with whom he had a son.
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In 342 BC, Aristotle accepted the invitation of Philippos the 2nd to visit Macedonia and become teacher of his son, Alexander. He was teaching him using the Homeric epics. Seven years later, Aristotle went back in Athens. There, he founded the Peripatetic school, which was modeled on Plato's Academy and quickly became a famous center of scientific research. Then, he began to write systematically his works. That was the time when he created most of them which refer to many sciences, such as physics, biology, zoology, psychology and metaphysics. There is no doubt that these projects constitute the first complete system of Western philosophy. [2]
Image 2: Aristotle teaches Alexander
Aristotle died in 322 BC, at the age of 62 in his mother's house in Halkida. The cause of his death was stomach disease. His body was transferred to Stagira where he was buried with great prices.
HIS WORK IN BIOLOGY As mentioned, growing up in family of doctors, Aristotle's interest for biology was something normal. From his work, we can easily realize that biology was one of his primary interests. In addition, the one quarter of his saved work were biology writings. His insightful observations, the classification of the elements and his theoritical editings show that he ahead of his times. He was the most significant biologist of antiquity [1] 3
Plinius mentions that Aristotle must have had great financial help and all the means thanks to the Macedonian kings, so that he could author his biology-related writings. While he was Alexander's teacher in Macedonian court, had the opportunity as well as the comfort to organize his infinite knowledge and enrich them with new observations based on physiology and physical sciences. In addition, during Great Alexander's campaign in Asia, several men were order to collect and send all the animals, the plants and in general weird things from the Asian area to a yard, so that Aristotle could study upon them and advance his work. Finally, according to Athenaus, Alexander helped him financially, funding money equivalent to 12 thousand euro. He wrote the book "Περί τα ζώα ιστορίαι (Stories about the animals)" and all the other writings related to physical sciences.[3]
Image 3: One of the many publications of Aristotle's first book
There is a possibility that he might have been tought the science of anatomy by his father. It seems that he examined the anatomy of fifty different animal species. It is also worth mentioning that although he might have not examined the anatomy of a human body, he was quite aware of the fetus' anatomy. The anatomy of the animals helped him on his research, resulting in the discovery of many things that noone knew since then and a lot of them are analyzed in detail in the "Stories about the animals" This book is the first that contains the observations of Aristotle. His observations and analysis has to do mainly with zoology and with biology. In his writings, he mentions about more than 500 animal species, a number very extraordinary for his era. However, his mentions are characterized with inequality. For some animals, he only gives nothing but a hint. For other animals, though, Aristotle describe them thoroughly. He describes in significant detail their different organs and part of their body, which he names "moria" (molecules),the consisting parts, the different ways with which they are reproduced, their nutritional habits, the habitats where they live and their behavior. His research fulfills a spectrum of land organisms, from man to snakes, serpents, insects and sea animals like fish, mollusk and seashell. For the topics that he didn’t have immediate knowledge, he was gaining information from any available resource. Those who helped him most were shepherds or hunters, pharmacists and fisher ofthe Aegean See. Most of his evidence comes from areas in Macedonia, Thrace and Troada.
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Many observations amazed later scientists. He realized that porpoise belong to mammals. He also distinguish the cartilaginous from the bone fish. As he distinctively mentions in the “Stories about the animals”, he observed the anatomy of octopus and that octopus uses his tentacles as hands, feet and a mean of reproduction simultaneously. He mentions that cuttlefish has the same characteristics. Those behaviors re – discovered in the 19th century. It is significant that he described thoroughly the growing of the novice and he located the appearance of the heart on the 4 th day after the egg was born, while he also noted the fours chambers of ruminants’ stomach. Another Aristotle‘s observation was that all the animals were prone to weather conditions. Some of them nest during winter while have the opportunity to emigrate in cool areas in summer and in hot areas in winter. The descriptions of the Lophius piscatorius, the hibernation and the vascular bed of mammals are in detail and were confirmed to be correct. Finally, Aristotle, described and the way of bee’s growing. [4]
Scala Naturae[1] According to W. Ross, Aristotle was not only the first to gather and recorded information on the species of animals, but also the first that attempted to classify them. In the book “Animal molecules” there is a very interesting analysis of the classification problem. The Platonic method of dichotomous division that already existed is subjected to three main objections. Aristotle thinks he should, in the course of the division, to introduce more differences from the beginning. In addition, we must recognize that there are large physical categories (maximum genera) like fish and birds that have many differences between them. He recognizes three degrees of similarity in the animal kingdom. These are: 1. Absolute type identity in one and the same species. 2. The similarity of the different species of the same maximum genera. Aristotle recognizes that these species have the same body members. The only difference is in the individual features of these members such as size, number, smoothness, etc. 3. Proportional similarity between higher generations. Aristotle is sure that the arm corresponds to the front leg, wing to fin, bone to thorn and feather to scale.
Image 4: Depiction of Aristotle's work
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Aristotle knows very well how the process of classifying animals has many difficulties. This happens because there are some individual animal species, which cannot be placed in one of the maximum genera (e.g. birds, fish) but also others that cannot be placed in a single genus but between two. However, its classification is clear in its basic lines and it seems to continue to respond positively over time. So, we conclude that Aristotle’s work was quite progressive for his era. The animals were placed by Aristotle in two broader categories, the animals with blood and the bloodless animals. These two categories currently correspond to vertebrate and invertebrate animals and have subdivisions. Humans belong to the animals that have blood which is an isolated species. This category is also composed of the animals that lay babies and animals that lay eggs. The main genera of the animals that have blood are cetaceans, birds, quadrupeds and the animals without legs. Finally, there are some intermediate species. The animals that don’t have blood are divided into classes according to the consistency of their internal and external members. According to this criterion, Aristotle distinguished the following categories: 1. Molluscs: They have a soft outer surface and the only hard substance is inside them. 2. Crustaceans: They have a hard-outer shell and a soft interior. 3. Shellfish: They have a harder outer shell than crustaceans and a soft interior. 4. Insects: It is hard both on the inside and the outside. Finally, Aristotle identifies some rare forms, which are half in the animal category and half in the plants category. Such forms are the sea anemones, the sponges, trepang and the jellyfish. However, each genus presents many differences. Aristotle recognizes that there are many ways of classifying animals. But he thinks the most enlightening is how they are born. Thus, animals can be classified into a scala naturae to the extent that the newborn develops after being detached from his mother's body. Aristotle observes that growth depends on the degree of organic heat that the generator has. Indeed, impressed by the important role that the heat has when eggs are hatched, led him to the conclusion that heat is the main aspect of any development. Based on this criterion considers how the blood in animals that have blood is warmer than comparable liquid that bloodless animals have. In addition, according to Aristotle, animals that have blood with lungs should be considered warmer than those who do not. This view stems from the fact that lung function is to moderate excessive heat. The upper animal species are the animals that lay eggs because they have so much organic heat that they can give birth to newborns that are of similar in quality to them. The next category is the animals that lay eggs that are perfect. This means that the eggs do not grow in size from the time they will be produced. The next in classification are the laying eggs that give incomplete eggs. However, at this point there is a special category of fish, the cartilaginous fish, which makes it difficult for those who have tried to classify animals, among them and Aristotle. This difficulty arises because while almost all fish give incomplete eggs, the cartilaginous fish give birth to newborns. Aristotle attributes this differentiation to a lack of heat from the parents. While they initially lay eggs, they keep them inside their bodies until they develop in newborns, because they have a soft shell and are thus they are not protected.
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The lower organisms in the classification are those that pass from the stage of the wormlarvae developed as a whole to form a living organism. Still lower in scale are the shellfish as they do not even produce larvae, only a slimy liquid. Finally, in the inferior species there is also the phenomenon of autogeny from dead matter, such as mud. Therefore, the classification resulting from all of the above and concluded by Aristotle is as follows.
Images 5,6 : Aristotle's scala naturae
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Reproduction[1] According to W.D.Ross, reproduction seems to have been particularly important to Aristotle, as his most remarkable observations and sharp analyzes refer to it. He was convinced that reproduction can be accomplished in three ways, with autogy (a notion that is not at all strange for that time, but was discarded later), with one parent or two parents. Reproduction by one parent concerns plants and stationary animals. Aristotle showed the greatest interest in reproduction by two parents and tried to answer two basic questions: what is the contribution of each parent and whether it comes from all of its body or from a specific part of it. After observations and arguments which he formulates, Aristotle concludes that the contribution of the male parent is to use the sperm in order to give shape in the matter provided by the female parent. He also thinks that the sperm, if it is within the body of the male parent, should be a physical part, like a tissue or an organ, or something non-physical, that is, a tumor, surplus product, morbid secretion or food. Of all the above, one can easily understand that sperm is excess fluid. Aristotle states that it is the surplus of useful food which is in its final form, ready to create tissue. The final form is characterized in the inbred animals as their blood and in the feral animals as the corresponding fluid. Moreover, since the sperm is obviously not blood, then it must be its direct product. Thus, most of the blood in a parent will form its tissues and what remains from it will form the sperm. That's why newborns look like their parents. It's because the sperm that will give them form resembles the main volume of blood that has generated the tissues of the parent. The corresponding excess blood in the female parent are the menses. The female, due to lower organic heat compared to the male, cannot transform this surplus into sperm. So, the menses work as the material cause of reproduction and sperm as the essential one. Next question answered by Aristotle is whether the parts of the newborn's body are preformed into the sperm or formed successively by epigenetisation. He answers that not all parts are present in the fetus. The theory that everything exists but is too tiny to be visible is not valid, because if it is, then the lungs should appear before the heart, since they are bigger. Neither the theory of one part producing the next may be true, because they should have the same form.Consequently, Aristotle believes that by sipping the sperm into the ovum, it begins in the second one a process of successive movements that differentiate it and develop its parts, that is, the parts of the fetus. In addition, since growth is the least vital function, it should be the first body part to be created has in it the principle of growth. Based on observation and theory, Aristotle concludes that this organ is the heart, as it will form the basis of development of the newborn as soon as it is detached from his mother's body. In order for new webs to be created we need blood. Blood flows through the blood vessels that start from the heart. Therefore, the heart is the beginning of all the other parts that will be created. As far as sex determination is concerned, Aristotle argues that it is a given from the moment of the conception and it depends on the organic heat that the fetus will have, which is proportional to the degree to which the sperm of the male parent has managed to master the matter provided by the female parent. Thus, sex is defined as male when the fetus has enough organic heat to to convert surplus blood into sperm. If he does not have this possibility, the fetus will be female and blood that it can not convert will be excreted with menstruation.
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Finally, heredity is based on the following principles: • When the male genitor prevails over the female, the offspring is male and resembles the father. • When the male parent is prevalent but its rush is modified by reaction of the female, the offspring is male and resembles the father's ancestors. • When the male parent only prevails as an individual, the offspring is female and resembles the father. • When the male parent only prevails as a male, the offspring is male and resembles the mother. • When the female parent prevails, the offspring is female and resembles her mother. • When the female generator prevails but its element is modified, the offspring is female and resembles the mother's ancestors. • When the rushes passed by the parents are confused, the offspring simply retains the characteristics of the species and does not resemble anyone. • When this confusion is even greater, the offspring retains only one character of the genus and is a monster that is at the cross between the parents' kind and another one.
ARISTOTLE TODAY Aristotle's works have greatly influenced today's biology. They formed the basis for subsequent observations and discoveries. Many of these were confirmed by scholars just a few centuries ago. It seems that Aristotle was very progressive compared to other scientists of his time. His thought and method is a standard for many, and most scholars so far admire him for everything he has done. He is the greatest biologist of humanity and his works still retain their diachronicity.
CONCLUSION From all of the above, we are led to the conclusion that Aristotle created very important projects. He rejected the perceptions that excisted until then and formulated new principles, new theories which he considered to be fuller and thus proved. His classification of animals, his observations, and the principles of animal reproduction have proven to be the most appropriate for the time being and have been the basis on which modern scientists have worked and expanded.
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BIBLIOGRAPHY – NETWORKING [1] W.D. ROSS, ARISTOTLE,3rd EDITION,NATIONAL BANK OF EDUCATION INSTITUTE ,ATHENS 2001 [2] https://el.wikipedia.org/wiki/Αριστοτέλης [3] https://ekivolosblog.wordpress.com/2013/11/30/ο-αριστοτελησ-και-το-βιολογικο-του-εργ/ [4] https://www.youtube.com/watch?v=i2NEkAhm96Y
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