The 3 differences between hominins and hominids
Hominins and hominids are two of the most relevant categories of primates. How to distinguish them?
Phylogeny and cladistics are branches of biology that aim to explore the kinship relationships between species and taxa. Previously, living beings were related on the basis of their morphological characters, but today, genetic studies have opened different paths and challenged the relationships between many animal groups.
How else to explain that, for example, an amphibian that was once a single species suddenly splits into five different population subgroups? Phylogenic relationships are mobile and subject to change, not because animals evolve very fast, but because humans have more and more tools to know them.
This leads to an increasing number of terminological divisions and confusion among the general population. This is the case, for example, of the words "hominid" and "hominin", two closely related terms that can generate a jumble of concepts in a person who is not fully dedicated to anthropology.
What are the main differences between hominins and hominids? Are you clear about which animal family we humans belong to? Do you know with which other living beings we share a taxonomic group? Today we give you answers to all these questions.
Differences between hominins and hominids: a matter of terms
First of all, it is essential that we make it clear that the term hominid refers to a "family", a systematic unit above the genus, but below the order.but below the order. Within the family aggregation, the different species can be grouped into subfamilies and infrafamilies, terms included in the "International Code of Zoological Nomenclature", whose purpose is to standardize the chaotic number of concepts that try to cover all animals on Earth.
On the other hand, the term hominin refers to a "subtribe".a taxonomic category between family and genus, this word being closer to the latter. As hominins are a more specific aggregation than hominids, it is not surprising that the former term is contained within the latter. Do not despair, for we explain it more kindly below.
As we have stated, hominins are a subtribe within the hominid family and are characterized by an upright posture and bipedal locomotion. We, human beings, are hominins as well as hominids.. Complex, but at the same time simple, right?
Here are some differences between these two groups (relative, of course, as one is contained within the other).
1. Members
As the groupings are two different concepts, a number of variable animals will belong to them.
For example, as hominids is a term that refers to a family, we can find many more species included in it than if we look only at hominins. Within the family Hominidae we find humans and the great apes, catalogued in these subfamilies:
- Subfamily Ponginae:includes the orangutans, the second largest primates in the animal kingdom.
- Subfamily Homininaecontains humans and their extinct relatives, gorillas and chimpanzees.
As we can see, this more general term does not exclude orangutans.a genus comprising three species that, according to studies, underwent a genetic divergence between them more than 2.5 million years ago. These great apes, native to Indonesia and Malaysia, are characterized by their large size (1.50 meters in length), their fine and dense reddish coats, and their arboreal habits. These primates present 3.1 % of genetic DNA differences with the rest of hominids grouped in closer subfamilies.
Chimpanzees and gorillas also fall within this large familyThey are found under the umbrella of the subfamily Homininae. The tribe Gorillini comprises the gorillas, huge, four-legged primates that share 98% of the human genome. They are highly intelligent, large, with black fur and habits that are surprisingly close to those of people in many cases.
Finally, the tribe Hominini is also found within the family of hominids, which includes the genus comprises the genus Pan and the genus Homo. The genus Pan comprises the species Pan paniscus and Pan troglodytes, the lifelong chimpanzees. Genetic studies show that these friendly primates underwent an evolutionary divergence from gorillas 7-8 million years ago, and from the genus Homo only 6 million years ago.
It is therefore not surprising that chimpanzees share up to 99% of the genetic code with us humans. These small primates, clearly humanoid in appearance, have hierarchical societies, are capable of deception and understand many human interactions. Because of our phylogenetic closeness, it is impossible to look a chimpanzee in the eye and not feel a certain part of ourselves in it.
Let's return to terminology after exploring the extended family Hominidae. In contrast, the subtribe Hominina (yes, which is part of the subfamily Homininae and of the tribe Hominini) contains only human beings, the species Homo sapiens. There is not much more to tell about this category, because that is what it was created for, to name only our species.
Following a small concatenation of terms, the classification of the human being would be as follows:
Order Primates - family Hominidae - subfamily Homininae - tribe Hominini - subtribe Hominina - genus Homo - species Homo sapiens.
If there is one thing we want to be clear about in this terminological hodgepodge, it is that all the great primates are hominids, but not all hominids are hominins.. Only we, the human species, are in the latter category.
2. bipedism
As we have seen, there is a key characteristic that produces differences between hominins and other hominids: bipedalism. It is clear that a chimpanzee can stand upright on its two forelimbs at specific times, but a fully bipedal locomotion and a skeletal readjustment for the same fully bipedal locomotion and a skeletal readjustment for it is a privilege only present in humans.. In nature, bipedalism is risky and costly for several reasons:
- Bipedal posture is not suitable for quick escape in dangerous situations.
- It places enormous skeletal stresses, especially on the spine.
- Changes at the pelvic level make the birthing period more difficult.
- It takes longer to learn to walk bipedally than in a quadrupedal mode.
Clearly, not all are disadvantages. Even if bipedalism did not emerge as an evolutionary response to human intelligence, this form of locomotion allowed us to use our hind limbs for the use and handling of tools, i.e. brain development.i.e. brain development.
Morphology
As many similarities as we hominins have with the rest of hominids, the morphological differences are also palpable, since it is enough to compare the photo of a person with that of a gorilla. For example, the rest of primates have prehensile feet, since the first toe of these is more robust and is aligned with the four remaining toes..
Height, weight, hair distribution and diverse muscular development are also morphological differences between hominins and other hominids. However, for example, we all have relatively large brains, we all have relatively large brains and an oral apparatus made up of 32 teeth.. Where differences are found, bridges are also built.
Conclusions
As we have seen in the previous lines, the term hominin is nothing more than an appraisal to differentiate the human being from the rest of the hominoid primates, i.e., orangutans, gorillas and chimpanzees.that is, orangutans, gorillas and chimpanzees.
In spite of the differences that we have tried to emphasize in this space, it is clear that when we compare ourselves with any other animal species, we have much more in common than different with all these primates. This is not a matter of chance, because somehow the 99% genetic kinship we show with chimpanzees has to be expressed.
If we get something clear from this dive into the phylogenetic history of the higher primates, it is that we are the only living hominid hominids as of today, but we share the family Hominidae with many other species of living beings. The differences between hominins and hominids, on a large scale and taking into account the diversity of the animal kingdom, are minimal.
Bibliographical references:
- Smith, B. H., & Tompkins, R. L. (1995). Toward a life history of the Hominidae. Annual Review of Anthropology, 24(1), 257-279.
- Steiper, M. E. (2006). Population history, biogeography, and taxonomy of orangutans (Genus: Pongo) based on a population genetic meta-analysis of multiple loci. Journal of Human Evolution, 50(5), 509-522.
- Zhang, Y. W., Ryder, O. A., & Zhang, Y. P. (2001). Genetic divergence of orangutan subspecies (Pongo pygmaeus). Journal of Molecular Evolution, 52(6), 516-526.
- Zoológica, N. (1999). Código Internacional de Nomenclatura Zoológica.
(Updated at Apr 12 / 2024)