Why is language unique to humans?

Sep 19, 2013
Why is language unique to humans?
Credit: © Demo

New research published today in Journal of the Royal Society Interface suggests that human language was made possible by the evolution of particular psychological abilities.

Researchers from Durham University explain that the uniquely expressive power of human language requires humans to create and use signals in a flexible way. They claim that his was only made possible by the evolution of particular psychological abilities, and thus explain why language is unique to humans.

Using a , Dr Thomas Scott-Phillips and his colleagues, show that the evolution of combinatorial signals, in which two or more signals are combined together, and which is crucial to the expressive power of , is in general very unlikely to occur, unless a species has some particular . Humans, and probably no other species, have these, and this may explain why only humans have language.

In a combinatorial , some signals consist of the combinations of other signals. Such systems are more efficient than equivalent, non-combinatorial systems, yet despite this they are rare in nature. Previous studies have not sufficiently explained why this is the case. The new model shows that the interdependence of signals and responses places significant constraints on the historical pathways by which combinatorial signals might emerge, to the extent that anything other than the most simple form of combinatorial communication is extremely unlikely.

The scientists argue that these constraints can only be bypassed if individuals have the sufficient socio- to engage in ostensive communication. Humans, but probably no other species, have this ability. This may explain why language, which is massively combinatorial, is such an extreme exception to nature's general trend.

Explore further: Evolution of snake courtship and combat behavior

More information: Scott-Phillips, T. and Blythe, R. Why is combinatorial communication rare in the natural world, and why is language an exception to this trend? Journal of the Royal Society Interface. dx.doi.org/10.1098/rsif.2013.0520

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3 / 5 (2) Sep 19, 2013
There are requirements for the development of language that are far more fundamental than what is involved in a "combinatorial communication system".
At the foundation is the ability to create associations between sounds/gestures/etc and external objects/actions. This is the basis of 'symbols'. Squirrels, for example, have different sounds for 'threat in the air' and 'threat on the ground.'
Next is the ability to share this association with other members of the same species, so when one squirrel chirps 'threat on the ground' a nearby squirrel will understand that there is a 'threat on the ground' from the sound alone, without having seen the threat.
No 'combinatorial' action is required, but symbolic communication has occurred.
1.9 / 5 (13) Sep 19, 2013
My cats and chook are all great communicators... you just gotta pay attention..

We are all one.

This study proves nothing.
1.5 / 5 (8) Sep 19, 2013
My cats and chook are all great communicators... you just gotta pay attention..

This seems to be about language communication in specific. You pets may be fantastic communicators but unless they're combining different meows and such to mean new things the study is still worth reporting. And if your pets are using language you should run like Hell. They are either possessed or too powerful to be safe around.
1 / 5 (7) Sep 19, 2013
I did once hear about a chimp using a vocabulary board and combining the word "bird" with "water" in regards to a duck it saw. Whether it was saying "waterfowl" or "a bird in water" it seems to be evidence of a possible combination of signs. Also, the study doesn't explain why other animals don't seem to have speech as such but merely proposes the existence of what could be a necessary phychological condition for later language evolution. A dolphin told me to add that last bit.
1 / 5 (5) Sep 19, 2013
"...tribes that were not only robust, but socially cohesive, skilled in organization, technology and weaponry (Darwin called this "superiority in the arts"), tribes that included "a great number of courageous, sympathetic and faithful members, who were always ready to warn each other of danger, to aid and defend each other", had genetically usurped other tribes (p. 199). As peoples highly endowed with social, but also military discipline, triumphed over others, "the social and moral qualities would tend slowly to advance and be diffused throughout the world"

-All this cooperating, communicating, teaching, observing, formulating, and executing required a complex and abstract language. Those tribes which were better at it would eliminate their competition... "by war, slaughter, cannibalism, slavery, and absorption" -Darwin

-The psychology is the result of this directed evolution.
1 / 5 (6) Sep 19, 2013
Signals are too crude a model to describe neural activity. Humans and other animals employ signs and symbols. Many species recognize and employ signs, which have only one context and humans also suffer from sign-locking as brand name advertising proves. Symbols evolve the present context and thus demand a greater awareness of the moment, this moment being the experience wrought by the symbol. Only fewer animals are able to pair objects and actions together to predicate, or express belief. Such brain wetware is required for planning, tool making, and religion

Powerful wetware allows a manipulation of the past by manipulating the symbols that embed pas memory moments. The human ability to make metaphor, or cloned copies of symbol as a blank canvas on which to express new ideas is the rarest of all traits in the animal kingdom. But probably not unique to humans
3.4 / 5 (5) Sep 19, 2013
Why is language unique to people?

That is an easy question to answer.

Answer: It isn't unique to people.

Next question...
5 / 5 (1) Sep 19, 2013
And perhaps this qualitative difference evolved when humans self-socialized or developed technology, both having a need to interpret others. The latter is perhaps again unique to humans, as only we have intentional master-apprentice teaching.

@tadchem: You are missing the point. Read the paper, it explains how symbolic communication is common but unless combinatorial an inflexible dead end.

@kochevnik: There is no qualification for "religion" needed. (And in fact, no one knows yet how it evolved.) In this work the minimal need is interpreting others, which is more simple than tool making.

Planning is a trait already in fishes. Symbolic thinking is even earlier, it is the basic process in cortexes/mushroom bodies and models have shown it selforganizes. It likely evolves because animals meet the same problem as computers. Computers overtrain on pattern matching making it useless fast, but we don't.
2.2 / 5 (10) Sep 19, 2013
One of my cats will climb onto my lap and make a peculiar lip-smacking noise ("I'm hungry."). This is his signal that he'd like to be fed. If I hold up my index finger ("Wait, I'm busy just now."), he sits patiently until I get up from the computer to feed him. Is language anything more, at it's roots, than a mutually understood set of symbols? If that's all it takes, then we have a language, and we are using it to communicate.
1.5 / 5 (8) Sep 19, 2013
Many species have language, as others have commented. How aBout some editorial filtering?
not rated yet Sep 19, 2013
I recall reading a genetic analysis of human genes involving 3 candidate genes characteristic of human speech, 2 branching less than 100 k years ago but also common to animals like mice ( obviously progenitor of Disney's Mickey), but the third dating to about 6000 BCE! If confirmed, food for thought or rebuttal.
3 / 5 (2) Sep 20, 2013
Language is difficult to quantify. Some animals have learned symbols, repeated sequences, dialects, self-identifiers. But what is it that makes humans unique?

Identification of mirror image with self, long childhood with intensive parental involvement, grouping into family units, socialization and hierarchy based on interaction. These are in a lot of animals. What is unique in humans? Constructs representing past events? Constructs representing future conditional actions?


Is it the storytelling - either reconstructing elaborate past sequences, or false sequences, that makes us human? The ability to detail a life never lead? I'd suggest this - the capability to both generate and understand a narrative - that lies somewhere near the heart of language.

Koko could lie. That's a start.
not rated yet Sep 20, 2013
Unfortunately there are no intermediate hominids left, displaying intermediate language skills. We are left to make what often amounts to educated guesses about how this very complicated chain of events unfolded*. That is why I take this kind of articles with a grain of salt.

*no, I am NOT a creationist.
3 / 5 (2) Sep 20, 2013
Why is language unique to humans?
For example, the dolphins even rats are squeaking in ultrasound all the time - how do we know, they don't communicate about their feelings like the bunch of teenagers during this?

Because we don't have consequent behaviors and coordinated actions that could bear this out.
not rated yet Sep 20, 2013
The Cuckoos (birds not readers) are amazing. Any one of several dozens reports here at physorg will convince readers this behavior can not come from a lack of language or any psychological deficient a language is asserted here to lack. You have to grasp the future to give your offspring away to surrogate parents.
Simply do a search with the word 'cuckoo' here on physorg.
not rated yet Sep 20, 2013
The cuckoo 'narrative' is astonishing.