As a result, the nervous system developed in a decentralised way, 8 providing a greater surface area to oxygenate in terms of total volume 9 Niven and Farris This miniaturisation strategy comes at a cost then: a cognitive limit of the individual, due to the concentration of oxygen.
Processing information no longer as individuals, but as a network, increased then the information processing capacity of the species, without renouncing to miniaturisation. Ants, for instance, communicate with dozens of different pheromones Jackson and Ratnieks : each ant leaves a track as it passes that acts as a signal for the next ant that passes that way, and each message is subsequently reinforced, weakened or changed by the other sisters in the colony.
Yogeesha and Pujeri It sounds like a miracle, but ants really can find the fastest route between a certain number of points. As the problem is one of the toughest in mathematics, for which no one including ants have yet found a completely satisfactory solution in other words valid for any number of cities , it is a noteworthy result.
As was the case when unicellular organisms organised themselves into complex organisms, the emergence of sociality in insects as a mechanism used to store and process information has not certainly been the dominant paradigm in science, but it is present. The bridge between simple circuits and the complex computational properties of higher nervous systems may be the spontaneous emergence of new computational capabilities from the collective behaviour of large numbers of simple processing elements Hopfield There is a long way to go from ants colony solving the salesman problem to Homo sapiens inventing GPS satellite system and creating car navigators.
But the road is marked out. The reasoning behind this is that, if a complex organism is altruist, this is encoded in the information code of each individual.
Cooperation can be one of the many effects of communication: first comes the ability to communicate, then the instinct to cooperate for a common scope. For human beings, cooperation without prior communication is something of a rarity. Many anthropologists who have lived with hunter-gatherer populations, say that learning the language was essential not only to their studies, but for their safety too.
Members of some species may reach tacit consensus about what kind of behaviour to tolerate or inhibit in their midst, but without language the principles behind such decisions cannot be conceptualized, let alone debated. To communicate intentions and feelings is one thing; to clarify what is right, and why, and what is wrong, and why, is quite something else Waal For Robin Dunbar, the anthropologist famous for proposing that group size was correlated with brain size among species of social primates, language lays the foundations of society.
Without gossip, there would be no society. But language does have something to say when it comes to hunting. Language in fact is fundamental if hunters are to peacefully share out game: it therefore emerges more as a means of negotiation Reader , rather than just gossip, or a way to pass on information. This goes for every means of communication.
The role of language and communication in general is also to make individuals feel — and therefore become — part of the system as a whole. Language permits the constitution of the social body , a structure where the single elements go beyond collaboration. We call it body for a reason: the citizens become the cells of an organism, they stop existing as a single element.
For Rousseau, in human societies, like in insect societies, the individual ceases to exist, and is alienated mainly thanks to shrewd communication — the conviction that every person has a well-defined role to play in society, and must play that role and no other. Language allows the emergence of collaborative societies, but not necessarily fair societies —exactly like ant colonies. Citizens under the social contract which is an emergent property in Rousseau writing, not an actual piece of paper are safer.
But certainly not more free or smarter than they were. If you wonder why the quadruplets, it appears that the particular shape of the uterus causes polyembryony. All humans have practically the same DNA in common, so altruism should be mandatory, total and undiscerning for all.
We should expect extremely altruistic behaviour also from chimpanzees and towards them too, as we have There are fossils of dragonflies with a wingspan of 70 cm and millipedes two metres long. In addition, insects exposed to an artificial atmosphere with a high oxygen content develop through the activation of some genes hypertrophic features Zhao et al.
For centuries we have known that an insect can survive for weeks after the part of the nervous system in the head has been removed Gregory The algorithm used by ants is… as simple as it can be, but not simpler. In a certain period of time the ants that chose the fastest path with have travelled back and forth several times, reinforcing the pheromone trails. After a while, the most distinct trail will be the fastest Dorigo and Gambardella The images or other third party material in this chapter are included in the chapter's Creative Commons license, unless indicated otherwise in a credit line to the material.
If material is not included in the chapter's Creative Commons license and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. Skip to main content Skip to sections. This service is more advanced with JavaScript available. Advertisement Hide. From Complex Organisms to Societies. Authors Authors and affiliations Mario Alemi.
Open Access. First Online: 04 December Download chapter PDF. Intelligence Needs Energy In order to understand the evolution of life in terms of the subjects covered in Chap. Internal selection, as Ludwig von Mises mentioned shortly after the fall of fascist regimes in Italy and Germany, seems to be there to favour tyrants: As every supporter of economic planning aims at the execution of his own plan only, so every advocate of eugenic planning aims at the execution of his own plan and wants himself to act as the breeder of human stock Mises First of all, the idea that information processing capabilities can spontaneously emerge is deeply-rooted in information technology and neuroscience: The bridge between simple circuits and the complex computational properties of higher nervous systems may be the spontaneous emergence of new computational capabilities from the collective behaviour of large numbers of simple processing elements Hopfield Even Frans de Waal, a primatologist famous for his idea that culture and morals are not exclusively human traits, acknowledges the fundamental role played by language in the formation of an ethical society: Members of some species may reach tacit consensus about what kind of behaviour to tolerate or inhibit in their midst, but without language the principles behind such decisions cannot be conceptualized, let alone debated.
Surely chimpanzees communicate, and do form collaborative societies. No other primate could live in cities as crowded as ours without starting a civil war. Achim, K. Structural evolution of cell types by step-wise assembly of cellular modules. Current Opinion in Genetics and Development, 27, — CrossRef Google Scholar.
Allman, J. Evolving brains. Google Scholar. Botha, R. The cradle of language Vol. OUP Oxford. Buchanan, M. The social atom. Calcott, B.
The major evolutionary transitions revisited. The MIT Press. Chitty, D. Do lemmings commit suicide?. Oxford University Press. Couzin, I. Collective cognition in animal groups. Trends in cognitive sciences, 13 1 , 36— Dawkins, R. The Selfish Gene. Journal of Chemical Information and Modelling, 53 9 , — Decho, A. Autoinducers extracted from microbial mats reveal a surprising diversity of N-acylhomoserine lactones AHLs and abundance changes that may relate to diel pH.
Environmental Microbiology, 11 2 , — Deneubourg, J. Collective patterns and decision-making. The high averages are due mostly to low death rates for infants and children but also to better sanitation, diet, and hygiene for most people, and to improved medical care for the old.
Life expectancy also varies among different socioeconomic groups and by sex. The most common causes of death differ for various age, ethnic, and economic groups. In the United States, for example, fatal traffic accidents are most common among young males, heart disease causes more deaths in men than women, and infectious diseases and homicides cause more deaths among the poor than among the rich. The human body is a complex system of cells, most of which are grouped into organ systems that have specialized functions.
These systems can best be understood in terms of the essential functions they serve: deriving energy from food, protection against injury, internal coordination, and reproduction. The continual need for energy engages the senses and skeletal muscles in obtaining food, the digestive system in breaking food down into usable compounds and in disposing of undigested food materials, the lungs in providing oxygen for combustion of food and discharging the carbon dioxide produced, the urinary system for disposing of other dissolved waste products of cell activity, the skin and lungs for getting rid of excess heat into which most of the energy in food eventually degrades , and the circulatory system for moving all these substances to or from cells where they are needed or produced.
Like all organisms, humans have the means of protecting themselves. Self-protection involves using the senses in detecting danger, the hormone system in stimulating the heart and gaining access to emergency energy supplies, and the muscles in escape or defense. The skin provides a shield against harmful substances and organisms, such as bacteria and parasites. The immune system provides protection against the substances that do gain entrance into the body and against cancerous cells that develop spontaneously in the body.
The nervous system plays an especially important role in survival; it makes possible the kind of learning humans need to cope with changes in their environment. The internal control required for managing and coordinating these complex systems is carried out by the brain and nervous system in conjunction with the hormone-excreting glands. The electrical and chemical signals carried by nerves and hormones integrate the body as a whole.
The many cross-influences between the hormones and nerves give rise to a system of coordinated cycles in almost all body functions. Nerves can excite some glands to excrete hormones, some hormones affect brain cells, the brain itself releases hormones that affect human behavior, and hormones are involved in transmitting signals between nerve cells. Reproduction ensures continuation of the species. The sexual urge is biologically driven, but how that drive is manifested among humans is determined by psychological and cultural factors.
Sense organs and hormones are involved, as well as the internal and external sex organs themselves. The fact that sexual reproduction produces a greater genetic variation by mixing the genes of the parents plays a key role in evolution. Among living organisms, much behavior is innate in the sense that any member of a species will predictably show certain behavior without having had any particular experiences that led up to it for example, a toad catching a fly that moves into its visual field.
Some of this innate potential for behavior, however, requires that the individual develop in a fairly normal environment of stimuli and experience. In humans, for example, speech will develop in an infant without any special training if the infant can hear and imitate speech in its environment.
The more complex the brain of a species, the more flexible its behavioral repertory is. Differences in the behavior of individuals arise partly from inherited predispositions and partly from differences in their experiences.
There is continuing scientific study of the relative roles of inheritance and learning, but it is already clear that behavior results from the interaction of those roles, not just a simple sum of the two. The apparently unique human ability to transmit ideas and practices from one generation to the next, and to invent new ones, has resulted in the virtually unlimited variations in ideas and behavior that are associated with different cultures.
Learning muscle skills occurs mostly through practice. If a person uses the same muscles again and again in much the same way throwing a ball , the pattern of movement may become automatic and no longer require any conscious attention.
The level of skill eventually attained depends on an individual's innate abilities, on the amount of practice, and on the feedback of information and reward. With enough practice, long sequences of behaviors can become virtually automatic driving a car along a familiar route, for instance.
In this case, a person does not have to concentrate on the details of coordinating sight and muscle movements and can also engage in, say, conversation at the same time. In an emergency, full attention can rapidly be focused back on the unusual demands of the task. Learning usually begins with the sensory systems through which people receive information about their bodies and the physical and social world around them. The way each person perceives or experiences this information depends not only on the stimulus itself but also on the physical context in which the stimulus occurs and on numerous physical, psychological, and social factors in the beholder.
The senses do not give people a mirror image of the world but respond selectively to a certain range of stimuli. The eye, for example, is sensitive to only a small fraction of the electromagnetic spectrum.
Furthermore, the senses selectively filter and code information, giving some stimuli more importance, as when a sleeping parent hears a crying baby, and others less importance, as when a person adapts to and no longer notices an unpleasant odor. Experiences, expectations, motivations, and emotional levels can all affect perceptions. Much of learning appears to occur by association: If two inputs arrive at the brain at approximately the same time, they are likely to become linked in memory, and one perception will lead to an expectation of the other.
Actions as well as perceptions can be associated. At the simplest possible level, behavior that is accompanied or followed by pleasant sensations is likely to occur again, whereas behavior followed by unpleasant sensations is less likely to occur again.
Behavior that has pleasant or unpleasant consequences only under special conditions will become more or less likely when those special conditions occur. The strength of learning usually depends on how close the inputs are matched in time and on how often they occur together. However, there can be some subtle effects. For example, a single, highly unpleasant event following a particular behavior may result in the behavior being avoided ever after. On the other hand, rewarding a particular behavior even only every now and then may result in very persistent behavior.
By definition, a tissue is an organization of a great many similar cells with varying amounts and kinds of nonliving, intercellular substance between them.
Organs are more complex units than tissues. An organ is an organization of several different kinds of tissues so arranged that together they can perform a special function. The epidermis is the outermost layer of skin. It consists of epithelial tissue in which the cells are tightly packed together providing a barrier between the inside of the body and the outside world.
Below the epidermis lies a layer of connective tissue called the dermis. In addition to providing support for the skin, the dermis has many other purposes. The dermis contains blood vessels that nourish skin cells. It contains nerve tissue that provides feeling in the skin. And it contains muscle tissue that is responsible for giving you 'Goosebumps' when you get cold or frightened.
The subcutaneous layer is beneath the dermis and consists mainly of a type of connective tissue called adipose tissue. Adipose tissue is more commonly known as fat and it helps cushion the skin and provide protection from cold temperatures.
System Organ systems are composed of two or more different organs that work together to provide a common function. There are 10 major organ systems in the human body, they are the:. These systems can best be understood in terms of the essential functions they serve, deriving energy from food, protection against injury, internal coordination and reproduction. Vorheriges Karussell. Was ist Scribd? Hochgeladen von Nuraini Zul.
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