Species can be defined as the most basic unit of classification and also a taxonomic rank. The next taxonomic rank on the hierarchy of biological classification may be a genus. On earth, there are currently 8.7 million species living today, however, that number is simply a fraction of all organisms that have ever lived.
This concept of species comes from the time of Aristotle. He used the term “génos”, which meant “a kind” (eg: fish), and “eidos”, which suggests “a specific form” (eg: tuna, sardine etc). These terms were eventually translated into Latin as “genus” and “species”, though they do not correspond to the terms under the Linnaean taxonomy.
Important Concept of Species
Four most important concepts of species are:
Typological Species Concept
In this concept, there's a finite number of sorts of living organisms that exist on earth. There is no relationship that exists between them and therefore they are termed as species. The difference is known as an unimportant and an irrelevant quality.
In their philosophies, Aristotle and Plato started this concept of species and Cain regarded the Typological species concept as the morphospecies concept in the year 1954 and 1956.
As the members of the species can be identified by their essential characteristics, therefore their group is referred to as essentialist species concept by the scientists.
The concept of Morphospecies states that the species can be differentiated from other species by their physical features and can be identified by their morphological attributes. This is called the Morphological Species Concept.
Nominalistic Species Concept
The nominalistic species concept is that the concept of Occam and his followers, of the assumption that nature only produces individuals. Species are the creation of man. In nature, they lack definite existence. These concepts do not have any scientific basis.
It believes that the species have been invented to refer to big numbers of individuals jointly. During the 18th century in France, this idea was in demand and even now employed by some botanists.
Biological Species Concept
A new concept known as the Biological species came into existence in the middle of the 18th century. K. Jordan was the first one to formulate this idea in 1905. Later in 1940, Mayr supported this concept. As per this idea , “a species may be a group of interbreeding natural populations that's reproductively isolated from other such groups”. Mayr described that the members of a species exhibit these attributes:
Reproductive Community: For the aim of reproduction the individuals of a species recognize each other as potential mates.
Ecological Unit: The species’ members differ from each other due to many attributes, but all the members cooperatively form a unit. They interact with other species in any environment as a unit.
Genetical Unit: Species comprises an outsized , inter-communicating gene pool, although the individual is just a non-permanent vessel comprising a little a part of the contents of the gene pool for a shorter duration.
Types of Species
Following are the different types of species:
It includes a group of morphologically similar organisms.
The population is obtained from a single parent.
In Biological species, the population that does reproduction in both sexual and asexual modes are involved.
It is a mixture of sexually reproducing organisms, phyletic lineages and uniparental organisms.
It includes phyletic lineages.
The planet earth consists of various kinds of living organisms as inhabitants. These living species are spread through various regions and grow in number through the process of reproduction. The species which moves to the verge of extinction or at a risk of extinction are known as endangered species. This occurs due to the sudden rapid decrease in the population or a loss of its critical habitat.
Factors Affecting Endangered Species
The living organism’s survival rate is affected by various factors such as hunting, loss of habitat, climate changes, diseases, pollution, and other natural calamities. The species which cannot survive these changes decrease in the number and fall under the endangered category. The rate of extinction in the present days is at peak level when compared to the earlier days. The reason for decrease in the number of organisms is due to deforestration, industrialization etc.
As an example, the Greater Horseshoe Bat, Loggerhead turtle, Siberian tiger, white-tailed eagle, and Bluefin tuna etc. According to the current statstics, around 1/4thof all mammal species available are in the endangered category. These Mainly affect the economical, legal, and ethical values. The globe loses its equilibrium since they constitute the major resources like food, shelter, medicines etc The conservation of habitat is required to protect biodiversity by restoring habitat. Various awareness programs have been introduced which explains the importance of protection of wildlife. NGOs and other agencies motivate others for conservation.