Difference Between Genus vs. Species

Main Difference

The main difference between Genus and Species is that Genus is a rank in the classification of the organism, below Family and above Species, and Species is the taxonomic unit, ranking below a Genus. A species is a group of populations in which genes are exchanged through the way of interbreeding or matting.

Genus vs. Species

Genus and Species are both the taxonomic ranks in the biological classification of an organism. The organism from a separate Genus cannot produce offspring that are capable of reproduction. Species is the largest group of organisms whose subspecies can breed and reproduce offspring which are able to reproduce as well. Genus comes just above the species in an organism’s taxonomic hierarchy whereas a species is the lowest and final level of the classification. Genus is composed of any number of species, but a Species is comprised of any number of subspecies having similar features. In the scientific classification of any organism first part of the name is called generic name while the second part of the name is known as a species name. The genus contains a large number of the organism while species contains less number of the organism. Genus is composed of different species while species is composed of different subspecies.

Comparison Chart

Genus is a rank in the taxonomic hierarchy, below family and above speciesSpecies is the closely related group of organisms which have similar features and able to produce fertile offspring through breeding
It is a Greek word which means RaceIt is a Latin word means the appearance
Rank in classification
Genus has a higher grouping than that of speciesSpecies is an essential and lowest level of classification of an organism
Different species made the genusSpecies consist of different subspecies
Number of Organisms
It consists of a large number of organismsIt consists of less number of organisms
The Part in the Binomial Name
The first segment of the binomial nomenclature name of a specific organism is called as the genusIn the binomial nomenclatural second part of the scientific name of an organism is called species
In Homo sapiens, Homo refers to the genusIn Homo sapiens, sapiens refers to species.

What is a Genus?

Genus is a rank in the taxonomic hierarchy that includes a large number of closely related species. Genus is a singular noun, and in plural form, it is “genera.” Organisms from separate genera cannot produce offspring that is capable of reproduction. A genus comprised of more than one species and these species have similar characteristics. The genus name of a specific individual is written in italics and is the first word of the scientific name of an organism. The first letter of the genus name is always capitalized.


The scientific name of humans is Homo sapiens, in which the genus name is Homo as the first segment of the binomial name of any particular organism is its generic name. Like as an abbreviation, it is common practice to capitalize the first letter of the genus name like (for example in case of (H. Sapiens). Genus names are sometimes given an English flavor to make it sound more usual. A genus name is also called as the generic epithet or generic name.

What is Species?

Species are the most basic and lowest level in a taxonomic hierarchy in which the group of organisms having similar features or attributes and capable of producing fertile offsprings. Individuals of the same species have identical chromosome counts; it means that they have an identical structure and form. Organisms in a species usually share the same features intrinsic only to their species. In taxonomy, any number of species may comprise a single genus, which makes it the ancestor of the species. The name of the species is the second part of an organism’s scientific name. It is generally written in italics and lowercase letters.


For example, in the case of the scientific name of humans, that is Homo sapiens. The second part of the scientific name of humans is its species name.

Key Differences

  1. In binomial nomenclature, the first part of the name is known as genus and second part of the name is called species.
  2. Different subspecies make the species and different species make the genus.
  3. Genus ranks below family, but species is the final level of binomial nomenclature.
  4. The genus contains a large number of organisms while species contains less amount of microorganisms.


The crux of content is genus and species are both the levels of a taxonomic name that is also known as the scientific classification of a specific organism. The genus includes those organisms that can produce those offspring that cannot reproduce fertile offsprings but species include those organisms that can interbreed to produce fertile offsprings.