In chemistry, chemical species is a chemical entity, such as a particular atom, ion, or molecule.  A chemical species, in technical terms, is defined as an ensemble of chemical identical molecular entities that can explore the same set of molecular energy levels on the time scale of the experiment. 
People as chemical species
In 1809, building on the logic of Swedish of naturalist Carolus Linnaeus, who had recently developed a Latin binomial classification scheme for plant species and who also suggested to his associate French chemist Antoine Lavoisier that all alchemical entities be classified in a similar manner, German polymath Johann von Goethe founded the science of human chemistry when he conceived the view of people as "chemical species", such as those found on the various chemical affinity tables of the 18th century, and wrote the scientific novella Elective Affinities on this view. 
● Human molecule
● Human particle
1. Daintith, John. (2004). Oxford Dictionary of Chemistry. Oxford: Oxford University Press.
2. Chemical species (PDF) – IUPAC Goldbook
3. Thims, Libb. (2007). Human Chemistry (Volume Two), (preview), (ch. 10 "Goethe's Affinities", pgs. 371-422). Morrisville, NC: LuLu.