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Science that deals with the study of the alive beings in your environment, is to say to the type of relations between the organisms and their environment.

It is divided in:

Autoecology, studies what surrounds to an individual, its activities, interactions and their relations with means.

Sinecology, study or knowledge of the groups with respect to the community.


  • Population: group of individuals of any class biótic
  • Community: All the populations that inhabit in a certain area
  • Ecosystem: Biótic community more physical environment
  • Habitat of a living being: place where ecological
  • Niche lives: physical space played by the organism and also its functional role within the community is to say the function that carries out
  • Biocenosis: biótic community
  • Biosphere: Biological system greater call also ecosphere and includes all the Earth organisms
  • Biogeocenosis: Ecosystem

The organisms from the ecological point of view can be classified in:

Holofitism or autotroph organisms, alive beings who feed themselves by themselves, elaborate the nutrients from organic matter and energy of the sun.

Holozoic or heterotrof organisms, depend indirectly for their direct feeding or on the autotrophs.


All the organisms depend on complex cycles and without them they could not exist. So that these cycles take place they must exist certain physical training conditionses (temperature, pressure, radiations...)


The life passes between close limits of temperature, the tolerated temperature depends on the considered alive being and his different biological stages, of this form we have:

a) High temperature: protozoos and certain seeds were found to temperatures of 85º, them alive beings the High oscillates between 42º and 52º, are certain species of seaweed that their High is of 4º, temperatures by you raise of the principles would carry the death of the alive being.

b) Minimum Temperature: it depends on the adaptations of the alive being, are alive beings (bacteria, leavenings, fungi) who can survive -270º, those that they die in the point of freezing of his liquids, those that has capacity to surpass the room temperature that surrounds to him (Ectothermics); those that maintain the temperature of their body at fixed level in spite of the variations of external means (endothermic) and those that varies their temperature within a margin (Heterotermes).

c) Optimal Temperature: one is between the lethal limits of Maxima and minim and is the place where the vital processes are carried out of more satisfactory form.

In most of beings alive, prolonged exhibitions to principles or minims they produce adaptation.

Pressure and radiations

The alive beings distribute themselves from places with high pressures to the deepest parts of the ocean. He is to say from pressures of 0.5 kg to more than 9000 kg. The sun emits radiations, from ultraviolet to longest.


They are the relations with the members of the same species. The type of locomotion has influence in the type of association between the individuals. Many associations of alive beings at random seem to be the result of groupings that provide advantages for the survival of the group (deer). The individuals of a same species are associated to obtain mutual benefit and arise the social organizations. In some there is work division and throughout the evolution their physical structures specialize reason why in a while given they do not exist single, independently of the social hierarchies that also exist (bees, ants).


A certain area is going to be defended actively by its occupants against the intrusión of other alive beings (nest, ...), sometimes the single territory is defended during the reproduction, the man is a territorial animal is to say to mark its borders.


It is the influence in the activity of an alive being by the behavior of another alive being, the man has many techniques of communication and the animals have similar but different schemes according to the species.

Communication by scent, is the most primitive technique, used to mark a territory, to defend themselves, for the communication between sexes during the reproduction.

Tactile, own communication of the social groups, some alive beings friccionan part of their body to recognize themselves.

Visual contact, appears in those alive beings that they have well developed the visual organ.

Auditory communication, is the developed method more of communication and with great varieties.


In the nature all alive being is related to members of other species and can happen: if in the relation of two different species effects are not exerted on any of the species because of the other denominates neutralism, if the interaction provides benefits for one of the species whereas in the other it does not influence denominates commensalism, if the association produces damage for one of them denominates parasitism or competition.

Negative heterotipic

Amensalismo: when a species is harmed by the presence from another one and to the other Operation does not happen anything to him

Competition, arises when one of the species has difficulties in the food obtaining, lodging... and both have resemblances biological necessities; parasitism, arises when the parasite obtains benefits to expenses of the lodger without causing the death to him; depredation, the species rapaz kills the prey and it is fed on her.

Positive heterotipic

Cooperation: when the individuals of different species obtain benefit, although both can separately live (marine crabs that has in their shells coelenterates)

Foresia: Association with unilateral benefit (flying insects that takes nematodes in their legs)

Commensalism: When one sees beneficiary and another one is not affected (insects that is in the nests)

Mutualism: Two individuals of different species are bound obtaining mutual benefit

Symbiosis: When two species are associated to live and they cannot do it the one without the other (lichens)