We commonly hear about species of living things. Who has never heard that a certain species, for example, has gone into extinction or that a new species has been discovered? But, after all, what is a species?
Over the years, several concepts were developed, and others were replaced, as it was observed that a species was much more complex than we could imagine. It is estimated that there are approximately 26 different concepts for this little word and none are completely accepted by the scientific community.
It is currently accepted that organisms of the same species are those found in the same population, which cross or have the potential to cross and produce fertile offspring under natural conditions.This concept was proposed by biologist Ernst Mayr (1904-2005).
According to this criterion, the physical aspect of organisms is not considered to define a species, although it helps in the definition. The physical characteristic is not used because there are organisms that have a lot of males and females. different and other organisms, however, which are extremely similar but not the same. species. For the researcher, what characterizes an organism as being of the same species is the ability to cross each other and produce offspring that will grow and be able to reproduce.
Bacteria reproduce asexually and do not fit the species concept
However, even the most widely accepted definition has its problems. When we think of individuals that reproduce among themselves, we do not take asexual reproduction into account. So how could we define a species of bacteria? Furthermore, there are different species that are able to cross each other and generate so-called hybrids, which, even though they are a rare event, can be fertile.
Did you see? Defining what is or is not a species is a very delicate process and that is why several concepts emerge as a way to fill a gap that another left. However, while the ideal concept is not created, Mayr's remains the most valid and accepted by the scientific community.
By Ma. Vanessa dos Santos
