A look at our place in the family tree:
It is useful to locate ourselves on the "family tree" used by biologists to show relationships among our planet's species. Human beings belong to the large mammalian Order of Primates, which has many members, living and extinct, and includes lemurs, monkeys, apes, and humans.
Examples of "family trees" can be seen at:
http://www.emc.maricopa.edu/faculty/farabee/BIOBK/BioBookHumEvol.html - this is a nice, simple one.
A more complicated tree can be seen at:
http://whozoo.org/mammals/Primates/primatephylogeny.htm
Within that Order, humans belong to the Family of Hominidae—or Hominids—which includes all erect-walking, man-like species, extinct or living. Within the Hominid family are a number of extinct erect-walking apes, our immediate ancestors, and ourselves.
We are members of the Genus Homo ("Man"), and our species name is Homo sapiens—"wise man." Sometimes we are further classified as a subspecies, Homo sapiens sapiens. All living humans are members of this subspecies and, although regional populations exhibit obvious differences from one another, all of us are quite closely related. There is, from a scientific point of view, but one human “race.”
Until recently, scientists classified the living ape species as distant cousins of human beings. The living great ape or pongid species include (from left to right) the gibbon; the orangutan; the gorilla (several sub-species); the chimpanzee; and the pigmy chimp or bonobo.
Genetic evidence from comparing our DNA with that of apes has led to new views of our degrees of relatedness. According to this line of evidence, Asian apes - gibbons and orangutans - are not as closely related to us as the African apes.
But human DNA is surprisingly similar to, and almost identical with, the DNA of chimps and gorillas. Both of these ape species have 48 chromosomes, we have 46. Chimpanzees share about 98% of our DNA; they even share the same ABO blood types with humans and can catch, and transmit, most human diseases. Both the DNA and anatomical evidence confirm that chimps are very close kin to us. The bonobo or pigmy chimp, which was only identified as a separate species in the 1930's, is genetically our closest relative. Bonobos even share the human characteristic of hidden estrus in females.
In 2007, the chimpanzee genome was analyzed, and that knowledge will provide additional insights into where and how, precisely, we diverged from these cousins. Analysis of the gorilla genome is currently under way.
New discoveries continually reinforce and extend our understanding of our relatedness to other life, while giving us clues about our own unique nature as a species.
