Hominin or Hominid?
What’s in a Name!
Philip L. Stein
Los Angeles Pierce College
The first step in wisdom is to call things by their right name.
Confucius
The classification of humans has always been problematical for one very important reason—
they are us! From the very beginning of scientific classification humans tended to be set apart
from other animals, although through time the breech became smaller and smaller. Early biologists such as Johann Friedrich Blumenbach and Georges Cuvier placed humans into their own
distinct order which emphasized what they considered to be the unique place of humans in the
natural scheme of things. Charles Darwin commented in The Descent of Man (1871), “If man
had not been his own classifier, he would never have thought of founding a separate order for his
own reception.”
It is an interesting footnote to history that Carolus Linnaeus in the 18th century believed that
humans were a subspecies of monkey. Later Linnaeus classified humans into a new animal
group, the primates, along with the monkeys, and bestowed on humankind the name Homo
sapiens or “wise man.” However, he seems to have been having second thoughts, alternating between Homo sapiens and Homo diurnus or “day man.”
The choice of words we use when communicating information can be essential to the understanding of that information. This is especially critical in selecting the words we use in discussing human evolution. Should we use the term human to refer to all members of the genus Homo?
Or should we restrict the term to anatomically modern Homo sapiens?
Most of us probably use semi-popular names that are derived from formal scientific designation. Thus Australopithecus becomes australopithecines; apes become pongids; and humans and
their ancestors the lived following the split from the common ancestor are the hominids.
The term hominid is derived from the name of the family Hominidae. This term is very
valuable in that it lets us get along just fine without having to resort to “man,” “people,” or “human” when we want to include extinct forms. Hominid is also neutral. For example, it does not
suggest any advanced cognitive abilities such as language or the ability to utilize symbols.
We tend to think of the Linnaean system of naming and classification as being stable. In
fact, it was precisely because of this perceived stability that it was adapted by the biological
community. But in fact it is far from stable. Even in the days of Linnaeus, when species represented divinely-creating “types,” the grouping of species into higher taxonomic categories was
open to considerable debate.
Once the decision had been made that the classification scheme was to represent evolutionary relationships, however, debates over the proper assignment of taxa became very important.
The placement of a species into a particular taxon is in effect making a scientific statement about
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how that species fits into the evolutionary history of life. However, our understanding of our
evolutionary past is constantly changing.
We can illustrate this problem by looking at the classification of the hominoids over the past
50 or so years. In all humility, let us examine the history of the classification over the nine editions of Stein and Rowe, Physical Anthropology. The first edition was published in 1974, and
the classification of the primates that was used was based upon the classification scheme of the
Napiers in A Handbook of the Living Primates (1967).
Order: Primates
Suborder: Anthropoidea
Superfamily: Hominoidea
Family: Hylobatidae (gibbons)
Family: Pongidae (orangutan, chimpanzee, gorilla, bonobo)
Family: Hominidae (humans)
From this taxonomy we derived the following useful terms:
Taxon
Suborder
Name of Taxon
Anthropoidea
Nontechnical Form
of Name
anthropoid
Included Living
Primates
all monkeys, apes, and
humans
Superfamily
Hominoidea
hominoid
all apes and humans
Family
Hylobatidae
hylobatid
gibbons
Family
Pongidae
pongid
great apes
Family
Hominidae
hominid
humans
However, evolutionary theory and the specific evidence of a particular evolutionary history
are continually changing. Colin Groves, in his review of primate classification (Primate Taxonomy, 2001) writes: “Because of new discoveries or hypotheses about interrelationships, alterations in classification are necessary. Taxonomy, like other fields of biology … is a dynamic science. Classifications are not engraved in stone, nor should they be….”
Continuing our stroll down memory lane, a change in the classification of primates in Stein
and Rowe appears in the fourth edition (1989).
Order: Primates
Suborder: Anthropoidea
Superfamily: Hominoidea
Family: Hylobatidae (gibbons)
Family: Pongidae (orangutan)
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Family: Panidae (chimpanzee, gorilla, bonobo)
Family: Hominidae (humans)
In this classification notice is given to the fact that the orangutans branched off of the lineage leading to the hominids significantly earlier than the branching among the African great
apes. A new term was introduced—panid. This change was largely in response to the work of the
molecular biologists who were using molecular evidence to work out the evolutionary ties
among various primate forms.
While the classification of primates in the text remained constant through the eighth edition,
a table was added in the sixth edition (1996) that presented as alternative classification those of
Andrews and Cronin (1982) and Andrews (1990). Many biologists and paleoanthropologists
were beginning to talk about abandoning the Linnaean system altogether and replacing it with an
entirely new system such as the proposed PhytoCode. Let’s look at the classification of Andrews:
Order: Primates
Suborder: Anthropoidea
Superfamily: Hominoidea
Family: Hylobatidae (gibbons)
Family: Hominidae
Subfamily: Ponginae (orangutan)
Subfamily: Homininae
Tribe: Gorillini (chimpanzee, gorilla, bonobo)
Tribe: Hominini (humans)
This latter taxonomy emphasizes the close relationships between humans and the African great
apes and introduces the term hominin after tribe Hominini. Of historical interest is the more extreme classification of Morris Goodman, also published in 1990. This taxonomy emphasis the
fact that the gorillas branched off the evolving ape line before the separation of the chimpanzees
and bonobos and humans.
Order: Primates
Suborder: Anthropoidea
Superfamily: Hominoidea
Family: Hominidae
Subfamily: Hylobatinae
Subfamily: Homininae
Tribe: Pongini (orangutan)
Tribe: Hominini (humans)
Subtribe: Gorillina (gorilla)
Subtribe: Hominina (chimpanzee, bonobo, humans)
This latter classification reflects a strong reliance upon molecular data, which after all is Goodman’s area of research. It emphasizes the close evolutionary relationship between the chimpanzee and bonobo on one hand and humans on the other. Others go to even a greater extreme placing the chimpanzee and bonobo into the genus Homo, but this has not caught on.
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Although the use of the term hominid for the lineage leading to ourselves remains in use
throughout the 1980s and 1990s, it has been slowly replaced by the term hominin, based upon the
tribe name Hominini. The term hominin today is the standard in the research world, and it is
working its way into the more popular and textbook world.
To complete the study to date, the ninth edition of Stein and Rowe (2006) has adopted a
consensus classification.
Order: Primates
Suborder: Anthropoidea
Superfamily: Hominoidea
Family: Hylobatidae (gibbons)
Family: Hominidae
Subfamily: Ponginae (orangutan)
Subfamily: Gorillinae (gorilla)
Subfamily: Homininae
Tribe: Panini (chimpanzee, bonobo)
Tribe: Hominini (humans)
If the popular terms are to be derived from the technical terms, we now have the following:
Taxon
Name of Taxon
Nontechnical Form of Included Living PriName
mates
Superfamily
Hominoidea
hominoid
All apes and humans
Family
Hominidae
hominid
Great apes and humans
Subfamily
Hominin
hominine
Chimpanzee, bonobos,
and humans
Tribe
Hominini
hominin
Humans
Today, several textbooks have adopted the new terminology, both in physical anthropology
and in general anthropology. Some authors discuss the issue in their Preface or Introduction. For
example, Agustin Fuentes, in the first edition of Core Concepts in Biological Anthropology
(2007) writes:
Under the methodology of science, when data do not support a hypothesis (such as the
Pongidae/Hominidae taxonomy), we must alter our hypothesis to fit the current data sets.
That is why in this book we used the classifications Homininae (chimpanzees, humans, and
gorillas), Ponginae (orangutans), and Hominini (humans and ancestors in our lineage since
the split with the other African apes.)
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Bernard Campbell, et al., in the ninth edition of Humankind Emerging, writes the following
in the Preface where the significant changes to this new edition are enumerated:
A thorough taxonomic revision of the human lineage that brings this text into agreement
with most modern paleoanthropological theories.
• The term hominid is widened to include members of the human lineage as well as all
great apes.
• Living humans and their ancestors since the split from the apes are placed in the Tribe
Hominini and are called hominins.
• Hominins are divided further into two Subtribes: Australopithecina (containing the australopiths of Africa) and Hominina (containing all living and extinct members of the genus Homo).
Not all textbook authors accept the new taxonomy. Alan Park is very explicit in his discussion of two different forms of taxonomy. The classification discussed above is ultimately based
upon cladistics or the order of branching. On the other hand, Park recognizes what he calls
phenetic taxonomy, a classification system based on existing phenotypic features and adaptations. Chimpanzees and gorillas resemble one another and are different from humans, and this is
reflected in the older taxonomy which he continues to use.
However, it is clear that hominin is going to replace hominid. In fact, of the 8 specialized
physical anthropology textbooks with copyright dates of 2004 or later, half use hominin in place
of hominid.
Textbooks Using Hominin
Boyd & Silk, How Humans Evolved, 4th ed., 2006
Campbell, Humankind Emerging, 9th ed., 2006
Fuentes, Core Concepts in Biological Anthropology, 2007
Stein & Rowe, Physical Anthropology, 9th ed., 2006
Textbooks Using Hominid
Jurmain & Nelson: Introduction to Physical Anthropology, 10th ed., 2006
Park, Biological Anthropology, 4th ed., 2005
Relethford, Fundamentals of Biological Anthropology, 6th ed., 2004
Stanford, Biological Anthropology, 2006
The hominid/hominin “debate” has already entered the public arena. In 2001 The National
Geographic referred to the Kenyapithecus platyops fossils as hominins. At the same time, the
report in the New York Times referred to the fossils as hominids, and several hundred emails
were received by National Geographic pointing out what the writers perceived as poor editorial
work. In an essay written by Lee Berger for the National Geographic News (December, 2001).
Lee notes that “Modern-day genetic research is providing evidence that morphological distinctions are not necessarily proof of evolutionary relatedness.” He further points out that:
In the long run, hominin is likely to win out against term hominid. It is more precise and
recognizes the biological reality that moves beyond physical morphology.
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So what’s in a name? The classification debate is not just a debate for the purist; it cuts
to the very core of our understanding of human’s place in nature and our evolutionary relationships with our closest living relatives. All hominins are hominids, but not all hominids
are hominins.
One could argue that the introductory student really doesn’t need to be aware of these technical debates. After all, it confuses an already confusing subject. But I disagree. I strongly feel
that as long as our students are taking Physical Anthropology to meet a science requirement and
as long as our course may be the only science course required we must be aware of the appalling
lack of science literacy among our students. Among our most important student learning objects
is the development of an understanding of the scientific method. For example, the gulf that is
widening between evolution and creationism is largely fueled by the failure of creationists to understand just how science works. This terminological debate is a great opportunity to discuss the
nature of science and the nature of science debates. In contrast to the Creationist worldview, the
world of science is not a static one.