ANN ARBOR—A new University of Michigan study provides the first evidence of transitive inference, the ability to use known relationships to infer unknown relationships, in a nonvertebrate animal: the lowly paper wasp.
For millennia, transitive
inference was considered a hallmark of human deductive powers, a form
of logical reasoning used to make inferences: If A is greater than B,
and B is greater than C, then A is greater than C.
But in recent decades,
vertebrate animals including monkeys, birds and fish have
demonstrated the ability to use transitive inference.
The only published study
that assessed TI in invertebrates found that honeybees weren’t up
to the task. One possible explanation for that result is that the
small nervous system of honeybees imposes cognitive constraints that
prevent those insects from conducting transitive inference.
Paper wasps have a nervous
system roughly the same size—about one million neurons—as
honeybees, but they exhibit a type complex social behavior not seen
in honeybee colonies. University of Michigan evolutionary biologist
Elizabeth Tibbetts wondered if paper wasps’ social skills could
enable them to succeed where honeybees had failed.
To find out, Tibbetts and
her colleagues tested whether two common species of paper wasp,
Polistes dominula and Polistes metricus, could solve a transitive
inference problem. The team’s findings were published online May 8
in the journal Biology Letters.
“This study adds to a
growing body of evidence that the miniature nervous systems of
insects do not limit sophisticated behaviors,” said Tibbetts, a
professor in the Department of Ecology and Evolutionary Biology.
“We’re not saying that
wasps used logical deduction to solve this problem, but they seem to
use known relationships to make inferences about unknown
relationships,” Tibbetts said. “Our findings suggest that the
capacity for complex behavior may be shaped by the social environment
in which behaviors are beneficial, rather than being strictly limited
by brain size.”
To test for TI, Tibbetts
and her colleagues first collected paper wasp queens from several
locations around Ann Arbor, Michigan.
In the laboratory,
individual wasps were trained to discriminate between pairs of colors
called premise pairs. One color in each pair was associated with a
mild electric shock, and the other was not.
“I was really surprised
how quickly and accurately wasps learned the premise pairs,” said
Tibbetts, who has studied the behavior of paper wasps for 20 years.
Later, the wasps were
presented with paired colors that were unfamiliar to them, and they
had to choose between the colors. The wasps were able to organize
information into an implicit hierarchy and used transitive inference
to choose between novel pairs, Tibbetts said.
“I thought wasps might
get confused, just like bees,” she said. “But they had no trouble
figuring out that a particular color was safe in some situations and
not safe in other situations.”
So, why do wasps and
honeybees—which both possess brains smaller than a grain of
rice—perform so differently on transitive inference tests? One
possibility is that different types of cognitive abilities are
favored in bees and wasps because they display different social
A honeybee colony has a
single queen and multiple equally ranked female workers. In contrast,
paper wasp colonies have several reproductive females known as
foundresses. The foundresses compete with their rivals and form
linear dominance hierarchies.
A wasp’s rank in the
hierarchy determines shares of reproduction, work and food.
Transitive inference could allow wasps to rapidly make deductions
about novel social relationships.
That same skill set may
enable female paper wasps to spontaneously organize information
during transitive inference tests, the researchers hypothesize.
For millennia, transitive
inference was regarded as a hallmark of human cognition and was
thought to be based on logical deduction. More recently, some
researchers have questioned whether TI requires higher-order
reasoning or can be solved with simpler rules.
The study by Tibbetts and
her colleagues illustrates that paper wasps can build and manipulate
an implicit hierarchy. But it makes no claims about the precise
mechanisms that underlie this ability.
In previous studies,
Tibbetts and her colleagues showed that paper wasps recognize
individuals of their species by variations in their facial markings
and that they behave more aggressively toward wasps with unfamiliar
The researchers have also
demonstrated that paper wasps have surprisingly long memories and
base their behavior on what they remember of previous social
interactions with other wasps.
The other authors of the new Biology Letters paper—Jorge Agudelo, Sohini Pandit and Jessica Riojas—are undergraduates...
(Source: BBC Future Can
the roots of spiritual behaviours and feelings be found in other
animals? First part. By Brandon Ambrosino 19 April 2019 .)
The article is written
from the viewpoint of a particular, namely Christian religious
tradition. But it operates with general paleoanthropological evidence
that pertains to the whole genesis of humankind.
wasn’t the only species to discover the benefits of food-sharing.
Neanderthals certainly pooled their resources, as did the several
species dating back two million years.””But food-sharing even
predates our Homo
ancestors, and is currently observed in chimpanzees
and bonobos. In fact, one recent paper even documented research of
sharing food with bonobos outside
of their own social group.”
While much of the
scientific study of religion is on theology-based doctrinal
religions, the evolutionary psychologist Robin Dunbar thinks this is
a narrow way of studying the phenomenon because it “completely
ignores the fact that for most of human history religions have had a
very different shamanic-like form that lacks gods and moral codes”.
(By shamanic, Dunbar means religions of experience that commonly
involve trance and travel in spirit worlds.) While the theology-based
forms are only a few thousand years old and characteristic of
post-agricultural societies, Dunbar argues that the shamanic forms
date back 500,000 years. These, he claims, are characteristic of
…some theorists such as
Dunbar argue that we should also look beyond the individual to the
survival of the group.
This is known as
multilevel selection, which “recognises that fitness benefits can
sometimes accrue to individuals through group-level effects, rather
than always being the direct product of the individual’s own
actions”, as Dunbar defines it.
An example is cooperative
hunting, which enables groups to catch bigger prey than any members
could catch as individuals. Bigger prey means more for me, even if I
have to share the meat (since the animal being shared is already
larger than anything I could catch alone). Such group-level processes
“require the individual to be sensitive to the needs of other
members of the group”, says Dunbar.
The similarities between
humans and chimps are well known, but one important difference has to
do with group size. Chimpanzees, on average, can maintain a group
size of about 45, says Dunbar. “This appears to be the largest
group size that can be maintained through grooming alone,” he says.
In contrast, the average human group is about 150, known as Dunbar’s
Number. The reason for this, says Dunbar, is that humans have the
capacity to reach three times as many social contacts as chimps for a
given amount of social effort.
How did nature achieve the
socialisation process? Jonathan Turner, author of The Emergence and
Evolution of Religionsays the key
isn’t with what we typically think of as intelligence, but rather
with the emotions, which was accompanied by some important changes to
our brain structure. Although the neocortex figures prominently in
many theories of the evolution of religion, Turner says the more
important alterations concerned the subcortical parts of the brain,
which gave hominins the capacity to experience a broader range of
As selection worked on
existing brain structures, enhancing emotional and interpersonal
capacities, certain behavioural propensities of apes began to evolve.
Some of the propensities already present in apes included: the
ability to read eyes and faces and to imitate facial gestures;
various capacities for empathy; the ability to become emotionally
aroused in social settings; the capacity to perform rituals; a sense
of reciprocity and justice; and the ability to see the self as an
object in an environment.
As the ape line evolved from our last common ancestor in more open environments, it was necessary to pressure apes, who prefer to go it alone, to form more lasting social structures. Natural selection was able to accomplish this astonishing feat by enhancing the emotional palettes available that had long been available to our ancestors…
The capacity to reflect on one’s sense of self is an important component of self‐awareness. In this paper, we investigate some of the neurocognitive processes underlying reflection on the self using functional MRI. Eleven healthy volunteers were scanned with echoplanar imaging using the blood oxygen level‐dependent contrast method. The task consisted of aurally delivered statements requiring a yes–no decision. In the experimental condition, participants responded to a variety of statements requiring knowledge of and reflection on their own abilities, traits and attitudes (e.g. ‘I forget important things’, ‘I’m a good friend’, ‘I have a quick temper’). In the control condition, participants responded to statements requiring a basic level of semantic knowledge (e.g. ‘Ten seconds is more than a minute’, ‘You need water to live’). The latter condition was intended to control for auditory comprehension, attentional demands, decision‐making, the motoric response, and any common retrieval processes. Individual analyses revealed consistent anterior medial prefrontal and posterior cingulate activation for all participants. The overall activity for the group, using a random‐effects model, occurred in anterior medial prefrontal cortex (t = 13.0, corrected P = 0.05; x, y, z, 0, 54, 8, respectively) and the posterior cingulate (t = 14.7, P = 0.02; x, y, z, –2, –62, 32, respectively; 967 voxel extent). These data are consistent with lesion studies of impaired awareness, and suggest that the medial prefrontal and posterior cingulate cortex are part of a neural system subserving self‐reflective thought…
The capacity to consciously reflect on one’s sense of self is
an important aspect of self‐awareness. A sense of self is a
collection of schemata regarding one’s abilities, traits and
attitudes that guides our behaviours, choices and social
interactions. The accuracy of one’s sense of self will impact
ability to function effectively in the world. A patient for whom
self‐awareness is compromised may have a sense of self regarding
abilities and traits that is not congruent with what others observe
(Stuss, 1991; Prigatano, 1999). For example, a brain‐injured
patient may feel he/she can competently return to the same level of
employment when observations by others indicate otherwise. When
asked, brain‐injured patients often underestimate their own
emotional dyscontrol, cognitive difficulties and interpersonal
deficits relative to a family member’s rating of their abilities
(Prigatano, 1996). Inaccurate self‐knowledge can significantly
impede efforts to rehabilitate brain‐injured patients, since they
may not appreciate the need for such treatment (Sherer et
al., 1998a, b).
Hughlings Jackson postulated that a sense of self is dependent
on the evolutionary development of the prefrontal cortex …
“Consistent and robust anterior
medial prefrontal and posterior cingulate activation during
self‐reflection was observed in all 11 participants. While the peak
of the activation varied somewhat between individuals, the
preponderance of activity was always within AMPFC, BA 9 and 10, and
posterior cingulate, in the area of BA 23, 30 and 31. Activation of
the anterior medial prefrontal region was consistent with our
hypothesis and with lesion studies of patients with impaired
self‐awareness (Stuss, 1991). The consistency and magnitude of the
activation was, however, somewhat greater than expected. “
is a Palaeolithic archaeologist and heritage consultant,
specialising in Neanderthals. Her first book Kindred: 300,000
Years of Neanderthal Life and Afterlife is due for publication
in 2019. She lives in Wales.
By the 1960s, it was widely believed that Neanderthals were
primarily carnivores who dwelt in frigid surroundings with very
little vegetation. This was in part based on ignorance of Indigenous
plant use in comparable habitats, but also because anthropology was
male-dominated, and particularly focused on the lives of big-game
hunters. Reactions against this perspective, however – including
from feminist scholars
– pointed out that a significant proportion of calories came from
the ‘slow and steady’ second part of the hunter-gatherer
equation: not only plants, but small-game hunting and fishing. In
reality, people who live by foraging are deeply embedded in their
environment, and everyone, including women, elders and young
children, takes part.
These shifts in perspective brought plants and creatures such as
birds back into the picture, but their evidence among Neanderthals
remained elusive in the archaeological record. The nadir came during
the 1980s, when scholars proposed that the vast amounts of bones and
teeth in Neanderthal sites weren’t even from hunting, but
scavenging. This left Neanderthals skulking around the fringes of
hyena or lion kills, grabbing scant scraps without invoking the ire
of ‘true’ predators.
However, this scenario was also overturned
as archaeology began to mature as a discipline throughout the final
decades of the 20th century. A new array of methods, and a growing
awareness of bias due to outdated excavation and collection
standards, brought our perception of Neanderthals into much sharper
resolution. In the decades since, evidence from hundreds of sites has
been meticulously parsed and amassed, revealing the Neanderthals as
top-level team hunters. They took on mighty beasts including bears,
rhinos and possibly mammoth, using finely honed wooden spears for
others were likely thrown like javelins.
The myth of speedy critters such as birds or rabbits being out of
reach has been crushed,
while seafood was at least sometimes on the menu. Strand-line
gathering was practised, whether for shellfish
or the odd washed-up marine mammal,
and maybe freshwater fish.
supplemented this varied carnivorous diet. Neanderthals made their
living across a huge geographical area, from North Wales down to
Palestine, and eastwards nearly halfway across Siberia, so it’s no
wonder we find preserved morsels of figs, olives, pistachios and date
palm in caves across the Mediterranean and West Asia. In
archaeological sediments and on stone tools, remnants of tubers
(wild radish, water lily) and seeds (wild cereal, peas and lentils)
have also been discovered. All this tells us that Neanderthals were
very likely chowing down on cooked food more diverse than meat.
Perhaps food was as important to social identity tens of millennia
ago as it is for us today.
What if the first Homo sapiens walked into dark caves to
find walls blazing with ancient visions?
Aside from the visceral satisfaction of a full belly, did the
Neanderthals experience passions at a more profound level? Were they
capable of self-expression, and abstract thought? Archaeologists are
nudging closer to affirmative answers. Paintings found at three caves
in Spain – La Pasiega, Maltravieso and Ardales – include
red-daubed stalactites and flowstone, a clean vertical line and, most
enchanting of all, a stencilled silhouette of a hand. Just recently,
scientists applied a dating technique measuring the radioactive decay
of uranium-thorium in the minerals encrusting the paintings, thereby
revealing a minimum age. The results were startling: the oldest
ranged from 67,000-52,000 years, appearing some 20,000-7,000 years
before we believe that H sapiens arrived in Europe. For many
scholars, this represents strong evidence that Neanderthals were
responsible. (Others are more hesitant: dating millimetre-thick
flowstone layers is complex, and some results
A Cave art at La Pasiega, Spain is dated by researchers at the
University of Southampton to between 67,000 and 52,000 years old.
Studies across Europe had already found that many cave paintings
rested on a substratum of red hand-stencils, lines and dots. The line
image at the La Pasiega site seems connected to a ladder-like form,
although the other parts might have been added later. Even so, the
findings raise the possibility that the first H sapiens
entering Europe’s caves walked into the darkness to find, not blank
canvases, but walls blazing with ancient visions. If genuine, these
discoveries have exposed a hidden layer of Neanderthal
self-expression, sitting beneath the more famous Upper Palaeolithic
oeuvre. Perhaps painting was even something our species actually
learned, rather than being the independent wellspring of art.
Some of the Neanderthals’ creations carry more than a hint of
the eldritch – structures so old that their attribution is
unquestionable. In the 1990s, hundreds of metres deep inside the
Bruniquel cave in southern France, researchers uncovered stalagmites
snapped off and arranged into two rings, encircling smaller piles.
But it was only in 2013, after a suspiciously old radiocarbon
measurement was taken, that researchers began studying them in
Over 174,000 years ago, it seems that Neanderthals walked into the
isolated chamber and carefully built these large circular structures.
More than 400 pieces from the central parts of the stalagmite columns
were placed in layers, some balanced on top of each other, others
standing in parallel. Many had been extensively burned, and blazes
had been kindled in the small piles. At least some of the fuel was
bone, potentially including bear, which isn’t easy to set and keep
alight. So far there are no artifacts, and no explanation for the
rings, but these structures would have taken time and planning to
create, and the foresight to provide sufficient illumination
underground. Research is ongoing – most excitingly, to see what
lies beneath the floor, entombed in calcium carbonate – but
Bruniquel has already opened a vista onto a Neanderthal mind as
elaborate as our own.
It’s important to add a note of caution to all this, since
Palaeolithic archaeology is still full of ‘unknown unknowns’.
It’s true that we have no fossil evidence for H sapiens
west of the Danube delta – never mind southern Iberia – before
45,000 years ago, which leaves Neanderthals as the chief suspects for
the paintings. But absence of bones does not prove absence of
hominins, and we know that H sapiens were making their way
into the Levant by at least 150,000 years ago. So the case is not
entirely closed for the cave art, even if the 3D creation at
Bruniquel seems secure. Still, these revelations have radically
altered our understanding, and expectations, of what Neanderthals did
in their daily lives – which now includes the possibility of more
Alongside the archaeological evidence, genetics is the second
pillar of the recent scientific reappraisal of the Neanderthals.
Increasingly refined data suggest that humans and Neanderthals shared
an ancestor around 800,000-700,000 years ago, before they split along
different evolutionary paths. This process could even have taken
place within genetically diverse but interconnected hominin
populations that evolved in Africa, and moved out from there to the
Near East and farther lands.
In 2010, researchers analysed
the genome of three Neanderthal individuals, and compared the data
with modern humans from various parts of the world. Based on genetic
links, it seems that some time after 200,000 years ago, early H
sapiens emerging from Africa interbred with Eurasia’s
indigenous hominin inhabitants. That’s why the genomes of all
living people – with the exception of those from sub-Saharan Africa
– contain a small percentage of Neanderthal DNA. However it
happened, the science is clear: to produce the amount of DNA
surviving today, taking into account complex processes of selection
against Neanderthal genes and less fertile hybrids, there must have
been an awful lot of sex between the communities.
This finding rocked the scientific world, and shredded the
‘replacement without interbreeding’ story of the Neanderthals’
decline. Living people preserve a stunning 20 per cent, maybe more,
of the Neanderthal genome, albeit as a somewhat tattered archive
that’s distributed between different populations. Even more
surprisingly, it’s not Western Europeans who have the most
Neanderthal DNA: East Asians have up
to a fifth more. There were also numerous phases of
hybridisation. The earliest known encounter happened more than
220,000 years ago, when a female ancestor of H sapiens mated
with a male Neanderthal – much earlier
than other known interbreeding between the two groups. At the other
end of the temporal scale, the jaw of a human who lived 40,000 years
ago in Romania reveals
that he counted a Neanderthal among his ancestors just four to six
generations back – right at the time when they were about to
disappear from the fossil record.
The girl was a first-generation hybrid: her mother Neanderthal,
her father Denisovan
In the same year as the Neanderthal DNA announcement, humans were
introduced to another long-lost cousin we didn’t even know we had –
and with whom we’d also merged. Since the 1970s, Russian scientists
had been excavating the Denisova cave in western Siberia. Among
thousands of bones they’d found was the tip of a child’s pinky
finger. Genetic analysis published
in 2010 revealed it to be an entirely unknown hominin population. The
‘Denisovans’, as they were called, were a ‘sister’ group to
the Neanderthals, branching
off around 600,000-430,000 years ago. A sizeable proportion of the
Denisovan genome survives in us, and scientists have pieced
together evidence that we interbred with them multiple times. Many
more Denisovans have now been identified at the same site, from tiny
scraps of bone or even DNA in the cave sediment itself. Yet we still
have no idea what these people really looked like, beyond the fact
some had dark eyes and skin.
In yet another twist, it turns out the Neanderthals and Denisovans
were close contemporaries, living in the same region for thousands of
years. During protein sampling aimed at locating more hominins among
unidentified bones from the cave, one stood out. Researchers had
upon a bone fragment from a girl, probably a teenager, who was a
first-generation hybrid: her mother a Neanderthal, her father a
Denisovan. Even more incredibly, her paternal ancestry revealed an
even older genetic record of mixing between these populations,
hundreds of generations before.
It’s hard to square these narratives of repeated contact and
reproduction with the archaeological record of the Neanderthals’
sudden demise. Everything we’ve found, whether from new excavations
or improved dating, has drawn the noose tighter around that period of
time around 40,000 years ago, when Neanderthals’ distinctive
skeletal and material remains disappear. Given the chronological
resolution that’s possible so far back, this is tantamount to an
almost simultaneous vanishing across their entire geographical range.
Yet the genetics shows that they were not extinguished, but rather
engulfed in a human flood. Hsapiens weren’t
their executioners so much as their assimilators.
It’s not clear how or why the encounters that led to
interbreeding took place. For starters, we shouldn’t treat
Neanderthals or early H sapiens as monolithic entities; in
reality, the population dynamics must have been enormously varied,
with groups spreading out and mingling in different ways in different
places. What about the result of all these trysts: with whom, and
how, were the hundreds, if not thousands, of hybrid babies raised?
Basic anatomy, combined with neurocognitive and psychological
research, both imply that these youngsters needed care, support and
love to survive and flourish – just as our own offspring do. But
does this mean that entire groups merged physically and culturally,
or that our mixed genetic dossier is the byproduct of a profusion of
‘one-offs’, accidental encounters that accumulated over 100,000
years? At present we can make only hazy guesses.
Beyond the advances in science, these changes in perspective on
Neanderthals are the fruit of a longstanding cultural obsession.
Since 1856, we have been trying to capture the likeness of these
people – and yes, Neanderthals must indeed be seen as people,
albeit of another kind. Yet the portrait is never finished. With each
new archaeological advance, they edge closer and closer to us,
feeding our hunger to know ever-more intimate details. Yet something
lurks: niggling, uncanny. Evolution has primed us with
extraordinarily sensitive face-detection capabilities, but this comes
with a deep-brain warning system. When faces are not obviously fake,
but fall short of hyper-realistic, they snag our reflex recognition
while also triggering alarm.
This disquieting aversion to aberrance, the so-called ‘uncanny
valley’ effect, was observed in people’s reactions to robots as
far back as the 1970s. One explanation for the ‘dyspathy’ it
evokes is a protective instinct, helping us recognise threats from
cadavers or the diseased. The Neanderthals induce something similar,
a mirror image of us in so many ways, yet somehow aslant. Their
liminal quality, at some anthropic edge, produces an uneasy tension.
We mentally flinch at the same time as being drawn towards them,
because they force us to reconsider how we mark the borders of
This is why the hand stencil at Maltravieso is so breathtaking.
It’s a manifestation of corporeality, proof that all those
untouchable skeletons in museum cases were once real, vital bodies.
Until that point, the rare cases of Neanderthal ‘trace fossils’
were little more than blurred outlines, mostly footprints at just a
few sites. A single, clear fingerprint was found around 50 years ago
during industrial open-cast mining in the foothills of the Harz
Mountains in Germany. It was imprinted on the surface of a piece of
soft birch tar. Cooked from bark, this is the world’s first
synthetic material, a natural glue used to join stone tip to wooden
handle. The Neanderthal who sat fashioning the tool 80,000 years ago,
wreathed in astringent fumes, was probably thinking about the near
future – how much longer the stone edge would last, when the season
would shift – little knowing these actions would stretch to a world
thousands of generations later, as a single finger pressed a whorl
into the softened tar.
Corporeal encounters with the Neanderthals can bewitch us because
they perform a sort of temporal sorcery. Hands pressed on cave walls
seem to imbue the rock with the memory of warmth; bodies moving
against each other 50,000 years ago become time-travellers in the
blood of their descendants. The changing visions we have conjured in
our imaginations are made manifest in how Neanderthals are
represented in artistic recreations – from the strikingly bestial
and depressed-looking creatures of the Victorian era, to the
exquisite digital portraits of the contemporary artist Tom Björklund,
whose Neanderthals certainly think, feel and dream as much as we do.
There is no cognitive chasm between us, just as there was no
Today, the story of the Neanderthals is still in flux. It is only
10 years since the watershed DNA discovery and subsequent demolition
of their status as evolutionary dead-losses. We now know there were
no Neanderthal endlings, no last lonely survivors. Many researchers
now question whether we can even think of them as a different
species. All the new evidence calls into question the way we have
theorised their lives, often involving lists of standards they must
meet to be considered genuinely human. ‘Modern’ behaviour has
always been a very particular version of how we like to think of
ourselves. A classic example – still being played out in arguments
of the La Chapelle site – is at what point are we prepared to grant
Neanderthals a conception of death? Too often, clear evidence for
special treatment of the deceased is not enough; only a perfectly cut
grave, the epitome of ‘proper’ Christian burial, is considered
proof of meaningful social practices.
The next step is to kick our habit of narcissism and
self-projection, and try to illuminate the Neanderthals on their own
Date de parution :
01/2017 Éditeur : Edizioni
dell’Orso Nombre de pages : 64 ISBN :
FRANCESCO BENOZZO & MARCEL OTTE
A New Theory on The Origins
of Human Language
It is crucial to bear in mind the following assertion recently made by two eminent paleoanthropologists: The relationship between modern anatomy, cognition, culture and language is a complex one, and cannot be captured by a single saltationary event, let alone by a single ‘gene’ acquired at a specific moment in our evolutionary history, leaving unambiguous traces in the fossil or archaeological record. This myth of a ‘modern human revolution’ is now totally rejected by paleoanthropologists and archaeologists, but it is disturbing to see it persisting – explicitly or implicitly – in discussion of language and cultural evolution…
Also Seyfarth & Cheney (2016) insist on this point, asserting that, “despite their differences, human language and the vocal communication of nonhuman primates share many features”. These common features suggest that “during evolution the ancestors of all modern primates faced similar social problems and responded with similar systems of communication and cognition”. In this respect, “when language later evolved from this common foundation, many of its distinctive features were already present”.
According to Hillert, 2015, “Australopithecus was already able to use […] referential vocalizations (possibly in combination with facial expressions and gestures) to display basic emotions and perceptions”; and Kimbel & Villmoare, 2016, state: “A fresh look at brain size, hand morphology and earliest technology suggests that a number of key Homo attributes may already be present in generalized species of Australopithecus, and that adaptive distinctions in Homo are simply amplifications or extensions of ancient hominin trends”. Their conclusion is that“the expanded brain size, human-like wrist and hand anatomy, dietary eclecticism and potential tool-making capabilities of ‘generalized’ australopiths root the Homo lineage in ancient hominin adaptive trends, suggesting that the ‘transition’ from Australopithecus to Homo may not have been that much of a transition at all”. Bringing together the PCP, Chomsky’s innatism, and the refusal of a conception of languages as evolving organisms, more concrete elements for inferring the existence of an articulated language in early humans from the Plio-Pleistocene can be offered by the four elements of deductive evidence indicated before [1) the lithic-geolinguistic correlation, 2) the millennial stability of languages, 3) the new discovers about the language of animals, and 4) the process of human world formation], linked to paleontological-archaeological considerations on Australopithecus [concerning its 4) anathomy, 5) habitat, 7) tools, and 8) bone remains]
As linguists and prehistorians working in the epistemological frame offered by the Paleolithic Continuity Paradigm, we can positively answer to the question luminously posed 20 years ago by Tobias. We would then point out the three following conclusions:
(1) Homo was born loquens (2.5 million years ago); (2) languages appeared with Homo himself; 3) language existed much earlier on (before 2.5 million years ago), with Australopithecus.
People utilize multiple expressive modalities for
communicating narrative ideas about past events. The three major ones
are speech, pantomime, and drawing. The current study used functional
magnetic resonance imaging to identify common brain areas that
mediate narrative communication across these three sensorimotor
mechanisms. In the scanner, participants were presented with short
narrative prompts akin to newspaper headlines (e.g., “Surgeon finds
scissors inside of patient”). The task was to generate a
representation of the event, either by describing it verbally through
speech, by pantomiming it gesturally, or by drawing it on a tablet.In
a control condition designed to remove sensorimotor activations,
participants described the spatial properties of individual
objects(e.g., “binoculars”). Each of the three modality-specific
subtractions produced similar results, with activations in key
components of the mentalizing network, including the TPJ,
posterior STS [posterior superior temporal sulcus], and
posterior cingulate cortex. Conjunction analysis revealed that these
areas constitute a cross-modal “narrative hub”that transcends the
three modalities of communication. The involvement of these areas in
narrative production suggests that people adopt an intrinsically
mentalistic and character-oriented perspective when engaging in
storytelling, whether using speech,pantomime, or drawing.
Theories of language origin can be divided into“vocal”
and “gestural” models (McGinn, 2015;Arbib,
& Wilcox, 2007;MacNeilage
& Davis, 2005;Corballis,
models posit that manually produced symbols evolved earlier than
those produced vocally and that speech was a replacement for a
preestablished symbolic system that was mediated by gesture
alone.Importantly, the kind of gesturing that gestural models allude
to is“pantomime” or iconic gesturing. Iconic gesturing through
pantomime is thought to have predated symbolic gesturing, passing
through an intermediate stage that Arbib (2012)refers
to as “proto-symbol.”
From a neuroscientific perspective, these theories of
language origin establish a fundamental contrast between two
different sensorimotor routes for the conveyance of language,
namely,the audiovocal route for speech and the visuo-manual route for
pantomime. Language is an inherently multimodal phenomenon, not least
through the gesturing that accompanies speaking (Beattie,
have yet a third means of conveying semantic ideas, and that is
through the generation of images, as occurs through drawing and
writing (Elkins, 2001).We
have argued elsewhere that the capacity for drawing is an
evolutionary offshoot of the system for producing iconic gestures
such as pantomimes (Yuan & Brown, 2014).Drawing
is essentially a tool-use gesture that “leaves a trail behind” in
the form of a resulting image. Overall, speech,pantomime, and image
generation comprise a “narrative triad,”representing the three
major modalities by which humans have evolved to referentially
communicate their ideas to one another.
Perhaps, the most important function of language is the communication of narrative, conveying the actions of agents, or“who did what do whom.”
[MISTAKE IN ORIGINAL TEXT. CORRECTLY: “WHO DID WHAT TO
Agency is one of the primary elements that is encoded in
syntactic structure (Tallerman, 2015).Although
word order varies across languages, 96% of languages place the
subject (the agent) before the thing that the subject acts
an “agent first” organization of sentences seems to be an
ancestral feature of language grammar (Jackendoff, 1999),and
gestural models of language origin highlight this type of sentence
organization as well (Armstrong & Wilcox, 2007).
Although language is well designed to communicate agency through
syntax, it typically does so in a multimodal manner, combining speech
and gesture. A basic question for the evolutionary neuroscience of
human communication is whether the conveyance of narrative is linked
to specific sensorimotor modalities (vocal vs. manual) or whether
there are cross-modal narrative areas in the brain that transcend
these modalities. This question led us to design an experiment in
which we would explore for the first time whether cross-modal brain
areas mediate the communication of narrative ideas using
speech,pantomime, and drawing as the triad of production modalities.
Most previous neuroimaging studies of cross-modal
communication are perceptual, and we are not aware of production
studies that have compared any pair of functions among
speech,pantomime, and drawing in healthy adults.
Both vocal and gestural models of language attempt to
account for the origins of syntax. As mentioned in the Introduction,
language grammar seems to have an intrinsically narrative structure
to it,being efficient at describing who did what to whom—in other
words,agency. Standard subject–verb–object models of syntactic
structure (Tallerman, 2015)essentially
encapsulate the kinds of transitive actions that we examined in our
headlines. A large majority of languages operate on an agent-first
basis, putting the actor before either the action or the target of
the action. To the extent that agency is one of the most fundamental
things that is conveyed in grammars (and which is lacking in
so-called proto-languages; Bickerton, 1995),then
our results have application to evolutionary models of language.In
particular, the imaging results that were obtained in the most purely
linguistic condition (speech) were replicated almost identically in
the nonlinguistic conditions of pantomime and drawing.This
cross-modal similarity suggests that the capacity of syntax to
represent agency can be achieved through nonlinguistic means
employing essentially the same brain network.
A number of biological theories of language propose that
syntax emerged from basic processes of motor
sequencing (Arbib, 2012;Fitch,
this might account for grammar’s connection with object-directed
actions—in other words, the gestural level of representation—it
may not do justice to the sense of agency that is well contained in
syntactic structure. Hence, we suggest that another important
evolutionary ingredient in the emergence of syntax—beyond the
“plot” elements contained in motor sequencing—would be the
incorporation of circuits that mediate the sense of agency, not
least“other” agency. To be clear, we are not arguing that the TPJ
and pSTS are syntax areas. We are simply suggesting that, whereas
circuits in the IFG [inferior frontal gyrus] more typically
associated with syntax (Zaccarella & Friederici, 2017)might
mediate the gestural level of language, the TPJ might have a stronger
connection with agents in the overall scheme of language,discourse,
and narrative. Agency can be conveyed linguistically through speech
and sign, but it can also be conveyed nonlinguistically through
pantomime (iconic gesturing) and drawing.
In this first three-modality fMRI study of narrative
production, we observed results that suggest that people generate
stories in an intrinsically mentalistic fashion focused on the
protagonist, rather than in a purely gestural manner related to the
observable action sequence. The same set of mentalizing and social
cognition areas came up with each of the three modalities of
production that make up the narrative triad, pointing to a common set
of cognitive operations across modalities. These operations are most
likely rooted in character processing, as related to a character’s
intentions, motivations, beliefs, emotions, and actions.
Hence,narratives—whether spoken, pantomimed, or drawn—seem to be
rooted in the communication of “other-agency.”
The Expression of the Emotions in Man and Animals is Charles Darwin‘s third major work of evolutionary theory, following On the Origin of Species (1859) and The Descent of Man (1871). Initially intended as a section of The Descent of Man, it was published separately in 1872 and concerns the biological aspects of emotional life. In this book, Darwin sets out some early ideas about behavioural genetics, and explores the animal origins of such human characteristics as the lifting of the eyebrows in moments of surprise and the mental confusion which typically accompanies blushing. A German translation of The Expression appeared in 1872; Dutch and French versions followed in 1873 and 1874. A second edition of the book, with only minor alterations, was published in 1890.
Before Darwin, human
emotional life had posed problems to the western
philosophical categories of mind
interest can be traced to his time
as a medical student and the 1824 reprint of Sir
Bell‘s Anatomy and
Philosophy of Expression which argued for
a spiritual dimension to the subject. In contrast, Darwin’s
biological approach links mental states to the coordination
of movement, and allows cultural
factors only an auxiliary role in the shaping of
expression. This biological emphasis leads to a concentration on six
emotional states: happiness, sadness, fear, anger, surprise and
disgust. It also leads to an appreciation of the universal nature of
expression, with its implication of a
single origin for the entire human species; and
Darwin points to the significance of emotional
communication with children in their
psychological development. Darwin sought out the opinions of some
leading British psychiatrists, notably James
Crichton-Browne, in the preparation of the book
which forms his main contribution to psychology.[
Amongst the innovations with this book are
Darwin’s circulation of a questionnaire
(probably inspired by his cousin, Francis
Galton) during his preparatory research; simple
psychology experiments on the recognition of emotions with his
friends and family; and (borrowing from Duchenne
de Boulogne, a physician at the Salpêtrière)
the use of photographs
in his presentation of scientific information. Publisher John
Murray warned Darwin that including the
photographs would “poke a hole in the profits” of the book;
and The Expression of the Emotions
is an important landmark in the history of book
Excerpts from “Epigenetics meets endocrinology” by Xiang Zhang and Shuk-Mei Ho
…1.We propose a three-dimensional model (genetics, environment, and developmental stage) to explain the phenomena related to progressive changes in endocrine functions with age, the early origin of endocrine disorders, phenotype discordance between monozygotic twins, rapid shifts in disease patterns among populations experiencing major lifestyle changes such as immigration, and the many endocrine disruptions in contemporary life. … 2.The inherited variability is static and does not change in response to the environment. The acquired variability can be caused by an environmental factor such as u.v. radiation from the sun (exogenous) or reactive oxygen species generated during metabolism (endogenous). But once acquired these effects are permanent and irreversible. Thus, inherited and acquired variability, either alone or in concert, cannot fully explain the high degree of variability and the reversibility of the endocrine system in response to the environment. … 3. Most cells or organs have various degrees of phenotypic plasticity, whereby the phenotype expressed by a genotype is dependent on environmental influences … Collectively, these findings indicate that nongenetic factors, including the environment, are important determinants of variability in endocrine function and risk of disorders. Endocrine glands and their target organs, because they function to maintain homeostasis in the body, must be highly responsive to environmental changes. … 4. A high degree of mismatch between the adaptive trait and the future environment, which includes aging, changes in lifestyle, or the introduction of new chemicals, pathogens, and pollutants, may increase the risk of developing disease. Prime examples are the strong correlations observed between hyponutrition and/or low birth weight with many endocrine disorders related to thyroid function, calcium balance, utilization of glucose, insulin sensitivity, and adrenal gland function (Vaag & Poulsen 2007, Hyman et al. 2009, Latini et al. 2009). … 5. The mechanisms underlying the interactions of genetics and the environment, which produce an adaptive phenotype in an endocrine axis, remain elusive. However, a growing body of literature suggests that the missing connection resides in epigenetics, a pivotal mechanism of interactions between genes and the environment (Jaenisch & Bird 2003, Cook et al. 2005, Jirtle & Skinner 2007, Tang & Ho 2007, Vaag & Poulsen 2007, Ling & Groop 2009; Fig. 1). … 6. Epigenetics links genetics with the environment in endocrine function. Hormone levels vary in response to internal and external environmental changes. Epigenetics, in response to exogenous and endogenous environmental cues, defines active and repressed domains of the genome. These responses explain the high phenotypic plasticity observed in the endocrine system, in which different genetic programs are executed from the same genome based on changes in the environment. … 7. Epigenetic modifications defined as heritable changes in gene function that occur without a change in the nucleotide sequence (Bird 2007, Goldberg et al. 2007, Berger et al. 2009). They are mitotically and transgenerationally inheritable (Rakyan et al. 2002, 2003, Hitchins et al. 2007) and potentially reversible (Bannister & Kouzarides 2005, Weaver et al. 2005). The most studied mechanisms known to affect the epigenome are DNA methylation, histone modification, and aberrant expression of microRNAs (miRNAs; Esteller 2005). These processes along with other epigenetic events determine when and whether various sets of genes are expressed in a tissue or cell. … 8. Histones are special proteins that facilitate the packaging of the DNA into nucleosomes, the basic building block of the chromatin. Posttranslational modifications such as acetylation, methylation, phosphorylation, sumoylation, and ubiquitination occur at specific residues in histones N-terminal tails (Cosgrove et al. 2004). These modifications determine whether the DNA wrapped around histones is accessible to the transcriptional machinery… In most instances, histone modifications work hand-in-hand with DNA methylation to achieve short- and long-term changes in transcriptional programs through transient or permanent reorganization of the chromatin architecture (Kondo 2009; Fig. 2). … 9. DNA methylation and histone modification are two major epigenetic mechanisms that corroborate in regulating endocrine-related gene expression. Packaging genes into active or inactive chromatin determines whether they are transcriptionally accessible or not. The N-termini of histones have specific amino acids that are sensitive to posttranslational modifications, which contribute to chromatin status. … 10. Epigenetics also plays important roles in regulating thyroid hormone and retinoic acid metabolism. For example, the expression of the sodium iodide symporter (SLC5A5), which is responsible for the uptake of iodine in the thyroid, was shown to be regulated by cytosine methylation of its promoter (Venkataraman et al. 1999, Smith et al. 2007). … 11. As a general observation, epigenetic dysregulation of the expression of type I receptor genes is closely linked to endocrine-related disorders including cancers of the breast, prostate, testis, and endometrium. DNA methylation dysregulates androgen receptor expression in prostate and endometrial cancer (Kinoshita et al. 2000, Sasaki et al. 2000), estrogen receptor-α in breast cancer (Yoshida et al. 2000, Archey et al. 2002, Adams et al. 2007, Champagne & Curley 2008), estrogen receptor-β in ovarian, prostate, and breast cancer (Zhao et al. 2003, Zhu et al. 2004, Zhang et al. 2007, Zama & Uzumcu 2009), and progesterone receptor in endometrial cancer (Sasaki et al. 2003). … 12. Peptide hormones are another major class of hormones, which have a broad spectrum of action, including regulation of energy metabolism (e.g. insulin), adiposity (e.g. leptin), growth (e.g. GH), and differentiation (e.g. FSH). … Disruption of the synthesis of peptide hormones or their cognate receptors by epigenetic events often leads to metabolic changes (e.g. obesity and metabolic syndrome; Plagemann et al. 2009) and abnormalities in neuropsychological behavior (e.g. autism and alcohol dependence; Gregory et al. 2009, Hillemacher et al. 2009), as opposed to cancer, the predominant disorder for epigenetic dysregulation of steroid hormones and their receptors (Widschwendter et al. 2004). … …Notably, epigenetic regulation of genes encoding peptide hormones or their receptors is largely related to developmental stage- and tissue-specific function or the development of a metabolic or neural disorder. For example, in cultures of mouse embryonic stem cells, the hypermethylated promoter of the insulin gene undergoes demethylation as these cells differentiate into hormone-producing cells; and in both the mouse and human insulin gene promoters, the CpG sites are demethylated in insulin-producing pancreatic β-cells but not in other tissues without insulin expression (Kuroda et al. 2009). … 13. In a recent study of autism-spectrum disorders, hypermethylation of the gene promoter encoding the oxytocin receptor was found to be associated with a reduced level of mRNA expression and was significantly associated with autism (Gregory et al. 2009). In another report, significant alterations of the mRNA expression and promoter-related DNA methylation of vasopressin were reported in patients with alcohol dependence (Hillemacher et al. 2009). … At the organismal level, the functioning of an endocrine axis involves multiple endocrine organs: for example, the hypothalamo–pituitary-gonadal axis comprising at least three hormone-producing tissues and many target tissues. The coordination of the entire axis, representing the first dimension of regulation controlled by genetic programs, is complex and meticulously well controlled. The interaction of these programs with the environment produces variable epigenomes, greatly amplifying the complexity of interaction and outcomes. These interactions can be viewed as the second dimension of influence…Finally, we will emphasize the effects of lifespan events that have strong modifying influences on epigenetics and pay special attention to windows of susceptibility during human development from conception to death. … 14. Genetics, environment, and stages of lifespan development interact in a three-dimensional space to create discordant endocrine phenotypes (epigenomes) from an identical genetic background (a single genome). … A widely studied area of epigenetics–environment– lifespan interactions is the relationship between birth weight and disease in later life. Animal studies have demonstrated that retardation of intrauterine growth results in progressive loss of β-cell function and the eventual development of type 2 diabetes in the adult. This association directly links chromatin remodeling with suppression of gene transcription (Simmons 2009). … 15. A review of human studies also indicated an inverse relationship between birth weight and susceptibility to endocrine metabolic disorders such as insulin resistance, type 2 diabetes, hyperlipidemia, and obesity (Godfrey 2006). … Insulin resistance is another example of epigenetic dysregulation resulting in the loss of function in an endocrine axis over time when it is constantly challenged by environmental changes such as specific dietary deficits. It is the condition in which normal amounts of insulin are insufficient to produce a normal insulin response from insulin-sensitive organs/tissues such as the liver, muscle, and adipose tissue, which all play an important role in the etiology and clinical course of patients with type 2 diabetes, high blood pressure, or coronary heart disease (Reaven 1993). … 16. Summary and perspectives It has become apparent that genetics alone is insufficient to explain the dynamic and complex interdependent relationships between the endocrine system and endogenous and exogenous environmental changes. … Epigenetics serves as a mechanism mediating the continuous `editing’ of the genome or epigenetic marks laid down in early life by exposures and experiences during later life. This paradigm has expanded the static and gene-centric view of phenotypic attributes to a more plastic and adaptive view molded by epigenetics. To fully understand the impacts of epigenetics on endocrine function and vice versa, we need a genome-wide search for plasticity genes or loci directly responsive to a specific environmental stimulus. To achieve this goal, current research is applying high-throughput investigative technologies to uncover global changes in the methylome(s), miRNA signatures, and the histone codes defining the interplay and advanced informatics to produce biologically meaningful data and conclusions. To advance these investigations, our focus should be placed on two commonly raised questions: 1) whether epigenetic changes induced by environmental exposures or lifestyle choices in one generation can be passed to the next and 2) whether these `inherited’ changes can be reversed upon removal of the exposures or through lifestyle modifications. Answers to the first question are of paramount importance to the primary prevention of endocrine disorders such as obesity, and answers to the second would open doors to the use of epigenetic drugs or interventions for the reversal of endocrine disorders with a strong epigenetic etiology. The opportunities of applying epigenetics to the prevention and treatment of endocrine disorders are limitless and certainly will emerge rapidly in the near future.
This reimagining of the periodic table, proposed by chemist
Theodor Benfey in 1964, emphasises the continuity of the elements
rather than imposing artificial breaks
By Joshua Howgego
RUN your fingers over the white keys of a piano. The notes get
higher and higher as your hand moves to the right. On the eighth key,
something beautiful happens: a note hangs in the air that embodies
something of the first, only with a different pitch.
We began to twig that something similar was going on with the
chemical elements more than 150 years ago. Scientists even called it
the law of octaves. And it is this repetition in the properties of
the elements that the
periodic table captures so beautifully. Similar elements end up
stacked in columns or groups. One group comprises noble gases like
argon and neon that barely react with anything, another contains
reactive metals, some of which, like francium, explode on contact
But there are doubts over whether the periodic table is in the
best possible configuration. Just as notes can be arranged in various
ways to produce music, so the essence of the relationships between
the elements could be depicted differently. There is no easy way to
judge which is better, or more “true”. So arguments over
perceived flaws in the current arrangement rumble on, with some
chemists arguing that certain elements should be relocated – and
others working on more radical ways to recompose the table.
At first, the
elements were organised by atomic weight. Now we order them by
the number of protons in their nucleus. We also know that their
properties are largely determined by the arrangement of the
negatively charged electrons that orbit in successive shells around
“One proposed redesign looks like a Christmas tree”
The lightest elements have just one shell, which can hold two of
these particles. Heavier elements have more shells that can hold
larger numbers of electrons. What really matters for each element’s
behaviour, however, is how many electrons it has in its outer shell.
That number tends to fit nicely with the way the table is
arranged, namely to place elements with similar properties in the
same group. For instance, group 1 elements have one electron in their
outer shell and those in group 2 have two. But it doesn’t always
fit together quite as neatly as all that.
Where does hydrogen go?
Take the first element. Hydrogen has one electron in its outermost
shell so you might assume it belongs exactly where it is, in group 1
above lithium and sodium, which also have one electron in their
outermost shell. Yet hydrogen is a gas, not a metal, so its
properties don’t fit.
The complication arises because, with an outer shell that can only
hold two electrons, hydrogen is one electron away from being full.
Given that elements yearn for full outer shells, that makes it very
reactive. In this sense, hydrogen resembles the elements in group 17,
namely the halogens like chlorine. Their outer shells need only gain
one electron to achieve a full shell of eight, which makes them
similarly reactive. In terms of its properties, then, hydrogen is
closer to chlorine than lithium.
Lower down the table there are no available spaces for misplaced
elements. Even so, a couple of the incumbents look like outliers.
Take mercury, also known as quicksilver because it is a liquid at
room temperature. In that sense, it is quite different to the other
members of group 12, including zinc and cadmium, which are all solid
metals. What gives?
The further down the table you go, the more of the positively
charged protons an element’s nucleus contains. This creates a
stronger pull on the orbiting electrons, meaning they must travel
faster and faster. By the time you reach mercury, the electrons are
travelling at 58 per cent of the speed of light. According to
Einstein’s special theory of relativity, this means their effective
mass is significantly higher than an electron’s normal mass, which
exacerbates the inward pull they feel.
The upshot is that mercury’s electrons orbit so tightly that
they can’t be shared to form bonds with other atoms, as is required
to make a solid. The same thing explains why gold is gold, a unique
colour among metals: relativistic effects change the way electrons
The F-block conundrum
Group 3 holds two elements that might belong elsewhere. As we move
across the upper rows of the table, electrons fill up shells in a
sequence of so-called orbitals, waiting until the innermost shell is
full before entering the next. By element 57, lanthanum, the
electrons begin to enter a new type of orbital, an f-orbital. To
account for this, most periodic tables hive off the elements making
up this f-block, putting it below the table, leaving a gap in group
Fair enough. But there is debate over which of the elements in the
f-block should come first. Some chemists maintain that the decision
should come down to electron configuration, which would leave the
table as it is, with lanthanum and actinium at the left-hand end of
the f-block. Others point out that chemical properties such as atomic
radius and melting point make lutetium and lawrencium, currently at
the right end, a better bet. In 2016, the International Union of Pure
and Applied Chemistry assembled a task
group to settle the argument. But no one expects a decision soon.
All these niggles have persuaded some chemists that we need to
redraw the periodic table – and there is no shortage of ideas. Mark
Leach at Manchester Metropolitan University, UK, keeps the internet
database of periodic tables, which contains hundreds of versions.
In an attempt to better represent the continuity where one row
currently ends, retired Canadian chemist Fernando Dufour developed a
3D periodic system that looks like a Christmas tree, with the
elements radiating from a trunk in circles that get larger closer to
the bottom. An alternative is the spiral developed by Theodor Benfey,
which allows the f-block to bulge outwards (see main image, above).
Eric Scerri at the University of California, Los Angeles, is among
those who has argued for more fundamental changes. He previously
proposed that the table could be arranged to maximise the number of
“triads”, sets of three elements that share similar properties
and are related by their atomic weights. These days, he is backing an
even more drastic approach: make the table not 18 but 32 columns by
slotting all 30 f-block elements between the current groups 2 and 3
long”). This allows the atomic number to run in an
Restrepo at the Max Planck Institute for Mathematics in the
Sciences, Germany, favours an alternative. He has explored whether
chemical similarity of elements in the same columns still holds as
well as it did 150 years ago, given our increased knowledge of
chemical reactivity. His conclusion is that lanthanum belongs in
group 3 – that is, out of sequence.
Redesigning the periodic table might seem a quixotic quest, but it
could soon take on a new urgency. We are already on
the trail of element 119. Where it will go, and how the table
will morph to make space for it, remains to be seen.