• What is commensalism?
• Commensalism and mutualism
• Examples of commensalism
• Commensalism in the desert
• Other types of interspecific relationships

We explain what commensalism is and its differences with mutualism. Also, examples and how it develops in the desert.

The phoresis occurs when the commensal uses another species to transport itself.

What is commensalism?

A specific type of interspecific biological interaction is known as commensalism, that is, of interaction between individuals of different species, characterized by the benefit of only one of those involved, without the other party receiving any type of damage or harm.

The term commensalism comes from the Latin cum Mensa, which translates as "sharing the table", and was originally used for those cases in which a animal fed on the scraps of someone else's food, as do the scavengers, which wait for the hunter to finish feeding. However, there are many other cases that can be understood as commensalism, such as:

• Foresis. It occurs when the diner uses another species to move from one place to another.
• Tenancy. In this case, the diner finds lodging in the member of the other species.
• Metabiosis or thanatocresis. The diner takes advantage of the excrement, remains or corpses of another species to protect themselves, reproduce or help themselves in some way.

Commensalism and mutualism

Some fungi live between the roots of certain trees exchanging nutrients.

Unlike commensalism, in which only one species involved benefits, in the case of mutualism it is both species that benefit from their interaction. This type of case is typical among species that present biological characteristics compatible with each other, being able to provide positive feedback, that is, to give mutual benefit.

This is the case, to cite an example, of mycorrhizae: mushrooms that make life between the roots of certain trees, exchanging nutrients and organic material (used by the fungus) in exchange for Water (usable by the roots of the tree). Both of them organisms they benefit.

Examples of commensalism

Some common examples of commensalism are:

• Remoras. Small saltwater fish capable of attaching themselves to larger, stronger animals such as sharks, to take advantage of their ability to swim fast and move from one place to another quickly.
• Sea acorns. A genre of crustaceans immobile seamen, they live on the shells of mussels, oysters and other bivalves, as tenants.
• Hermit crabs. With a soft abdomen, they take advantage of the empty shells of sea snails to enter and protect themselves, as if it were their own.
• Certain species of epiphytic plants, not parasites. They live on the branches of large trees, thus accessing levels of sunlight that at the level of I usually they are scarcer.

Commensalism in the desert

Some burrows are abandoned and inhabited by other species.

The habitat desert is one of the most extreme in the world and its Flora and fauna it is adapted to your difficult climatic conditions. This does not prevent them from forming commensal relationships, although they certainly occur less frequently than in others. environments more kind. Examples of this are as follows:

• Burrows dug underground by rodents are often abandoned, and then other species can inhabit them and flee to the ground. Sun, as do certain types of snakes and scorpions.
• The owls and owls of the desert They take refuge in holes made by other species inside the cacti, taking their young there and gaining protection from the sun and other species.
• The prey birds They are frequent in the desert, like certain species of vulture, and they feed on any organic debris resulting from the hunt of larger species.

Other types of interspecific relationships

In predation, one individual kills another for nutritional benefit.

In addition to commensalism and mutualism, which we have already discussed, there are the following types of interspecific relationships:

• Parasitism. It occurs when one species benefits from the other nutritionally or otherwise, that is, it obtains benefits from it, but in this case causing damage of some kind. A perfect example of this are mosquitoes, which feed on the blood of animals to incubate their eggs, and in return can transmit diseases to which it acts as a contagion agent.
• Symbiosis. It is a very narrow degree of mutualism, in which the species involved end up becoming codependent, that is, needing the presence of the other to survive or to be able to complete their life cycles. A good example of this is the relationship between an alga and a fungus to form a lichen, exchanging structure for humidity and nutrients.
• Competence. Quite the opposite to commensalism, it occurs when two species compete or face each other for access to the necessary resources to survive, so that only one of them will be able to obtain a benefit. This is the case, for example, of the competition between hyenas and vultures, or other African scavengers, to devour the remains of the hunt of the lions.
• Predation. The fundamental type of interaction in the food chain, consists in that one species (the predator) hunts and devours another (the predator) dam), thus obtaining a nutritional benefit and ending the existence of the other. This is what happens when a fox hunts a rabbit and eats it.
• Amensalism. In this case, the interaction between the species is detrimental to one of them, without the other obtaining any benefit in return. This is the case with trees such as Eucalyptus or Walnut, for example, which prevent the growth of other vegetable species around him, without being directly benefited in the process.