The biological species concept defines species by the ability to interbreed and produce fertile offspring, emphasizing gene flow within a species. Its limits include extinct organisms, asexual species and cases where distinct forms exchange genes.
A species is often defined as a group of similar individuals that interbreed in nature and produce fertile offspring. Discuss some problems with the use of this definition.
a not all organisms can be defined in this way / does not take into account hybrids/ microorganisms/plants;
b. (even if able to interbreed) may have differences in DNA/protein;
c. does not apply to bacteria/other organisms that reproduce asexually;
d. in sympatric/allopatric isolation members of the same species do not interbreed;
e. (in some species) significant differences in morphology can occur within the same species eg: sexual dimorphism/metamorphosis/ring species;