The term biology was coined in the late 1700s by the French naturalists Pierre-Antoine de Monet and Jean-Baptiste de Lamarck. It is the science of life: Of the composition and behavior of living things, of their interactions with each other and their environment.
Biologists study life over a wide range of scales:
One the central, organizing concepts in biology is that all life has descended from a common origin though a process of evolution. Charles Darwin was the first to rigorously argue this idea, which he did with his proposal of natural selection as an evolutionary mechanism. The evolutionary history of a species, i.e., the characteristics of the species from which it descended, is called the phylogeny of the species; it is studied using methods of molecular biology by analyzing biopolymer sequences of genes and proteins, and by investigating ancient forms of life in paleontology. Various methodologies have been developed, including phylogenetics, phenetics, and cladistics. An evolutionary timeline outlining the major events in the evolution of life on Earth is available.
The classification of living things is called systematics, or taxonomy, and should reflect the evolutionary trees (phylogenetic trees) of the different organisms. Taxonomy piles up organisms in groups called taxa, while systematics seeks their relationships. The dominant system is called Linnaean taxonomy, which includes ranks and binomial nomenclature. How organisms are named is governed by international agreements such as the International Code of Botanical Nomenclature[?] (ICBN), the International Code of Zoological Nomenclature (ICZN), and the International Code of Nomenclature of Bacteria[?] (ICNB). A fourth Draft BioCode was published in 1997 in an attempt to standardize naming in the three areas, but it does not appear to have yet been formally adopted. The International Code of Virus Classification and Nomenclature[?] (ICVCN) remains outside the BioCode.
Traditionally, living things were divided into five kingdoms:
However, this five-kingdom system is now considered by many to be outdated, and if one does not want to hyperinflate the number of kingdoms, one can use the three-domain system. These domains reflect whether cells have nuclei or not as well as differences in cell membranes / cell walls.
Major Branches of Biology
People and History
What are our priorities for writing in this area? To help develop a list of the most basic topics in Biology, please see Biology basic topics.
External links and Resources
On the Web