Author: Hannah

New Book. New Ideas?

A new book is to be published on May the 24th. By John F. Hoffecker the book is entitled “Landscape of the Mind: Human Evolution and the Archaeology of Thought” – it aims to look at the emergence of human thought and language through archaeological evidence

Archeologists often struggle to find fossil evidence pertaining to the evolution of the brain. Thoughts are a hard thing to fossilize. However, John Hoffecker claims that this is not the case and fossils and archaeological evidence for the evolution of the human mind are abundant.

Hoffecker has developed a concept which he calls the “super-brain” which he hypothesises emerged in Africa some 75,000 years ago. He claims that human’s ability to share thoughts between individuals is analogous to the abilities of honey bees who are able to communicate the location of food both in terms of distance and direction. They do this using a waggle-dance. Humans are able to share thoughts between brains using communicative methods, the most obvious of these being language.

Fossil evidence for the emergence of speech is thin on the ground and, where it does exist, is quite controversial. However, symbols emerging in the archaeological record coincides with an increase in evidence of creativity being displayed in many artifacts from the same time. Creative, artistic designs scratched on mineral pigment show up in Africa about 75,000 years ago and are thought to be evidence for symbolism and language

Hoffecker also hypothesises that his concept of the super-brain is likely to be connected to things like bipedalism and tool making. He claims that it was tool making which helped early humans first develop the ability to represent complex thoughts to others.

He claims that tools were a consequence of bipedalism as this freed up the hands to make and use tools. Hoffecker pin points his “super-brain” as beginning to emerge 1.6 million years ago when the first hand axes began to appear in the fossil record. This is because hand axes are thought to be an external realisation of human thought as they bear little resemblance to the natural objects they were made from.

By 75,00 years ago humans were producing perforated shell ornaments, polished bone awls and simple geometric designs incised into lumps of red ochre.

Humans are known to have emerged from Africa between 60,00 to 50,000 years ago based on archeological evidence. Hoeffecker hypothesises that – “Since all languages have basically the same structure, it is inconceivable to me that they could have evolved independently at different times and places.”

Hoeffecker also lead a study in 2007 that discovered a carved piece of mammoth ivory that appears to be the head of a small figurine dating to more than 40,000 years ago. This is claimed to be the oldest piece of figurative art ever discovered. Finds like this illustrate the creative mind of humans as they spread out of Africa.

Figurative art and musical instruments which date back to before 30,000 years ago have also been discovered in caves in France and Germany.

This looks to be nothing new but archaeological evidence is something which a lot of people interested in language evolution do not often discuss. I also don’t really know what to think of Hoeffecker’s claim that “all languages basically have the same structure”. What do you think?

Cultural Transmission observed in Whales

A new paper in Current Biology, published today has revealed that the songs of Humpbacked Whales are passed through the ocean by mechanisms of cultural transmission.

Cultural transmission is defined as the social learning of information or behaviours either over generations or via peers. It has been seen to occur in primates, cetaceans and birds.

Cultural transmission over generations, i.e. parent passing socially learnt traits to their offspring, is known as vertical transmission and cultural transmission via peers, unrelated individuals from within generations, is known as horizontal transmission. In humans, languages and memes are transmitted, learned and (in a lot of cases) evolved in this manner.

Male humpback whales have a repetitive and evolving ‘song’ which acts as a vocal sexual display. This song is highly repetitive and is used, by mechanisms of social sorting and attraction, to allow for sexual selection within the whale population. All males within a population are known to conform to the current version of the display (song type), and similarities have been seen to exist among the songs of populations within an ocean basin.

The study being discussed presents very strong evidence for patterns of horizontal transmission, whereby song types spread unidirectionally and rapidly in the pacific ocean eastward through populations in the western and central South Pacific. The study was done over an 11-year period. This is the first documentation of a repeated, dynamic cultural evolution occurring across multiple populations at such a large geographic scale and across such a large time scale.

The patterns of cultural transmission seen in these whales songs are analogous to the same mechanisms we see in humans given that the songs are subject to mistakes and changes which are replicated. This causes the same mechanisms we see in the cultural transmission of language. The authors note that the level and rate of change seen in the whales is unparalleled in any other nonhuman animal and involves culturally driven change at a vast scale.

They also state that:

Investigating the underlying mechanisms of song evolution may yield powerful insights into the transmission of cultural traits and the evolution of culture and plasticity in sexually selected traits.

They also observed that at least one of the song types was transmitted between two different ocean basins, the Indian and South Pacific Ocean. It’s amazing to think how far a single song type can be horizontally transmitted.

Humpback whale song is unique among the animal kingdom due to the conformity to the current norm. This is coupled with high plasticity in the trait (ability to change their song based on whatever the new ‘norm’ is). Why both plasticity and conformity might be selected, how these interact with sexual selection, and how cultural evolution influences both are intriguing questions in need of consideration.

References

Garland, E. C.; Goldizen, A. W.; Rekdahl, M. L.; Constantine, R.; Garrigue, C.; Hauser, N.; Poole, M. M.; Robbins, J.; Noad, M. J. (2011) Dynamic Horizontal Cultural Transmission of Humpback Whale Song at the Ocean Basin Scale. Current biology : CB doi:10.1016/j.cub.2011.03.019

The Parental Antagonism Theory of Language Evolution

Human Biology are publishing a special issue on “Integrating genetic and Cultural Evolutionary Approaches to Language” this month! Abstracts for all of the papers can be found here.

William Brown‘s paper has been published on his blog ahead of the boat today. The Abstract is below and there is a link to the paper at the bottom.

Language—as with most communication systems—likely evolved by means of natural selection. Accounts for the natural selection of language can usually be divided into two scenarios, either of which used in isolation of the other are insufficient to explain the phenomena: (1) there are group benefits from communicating, and (2) there are individual benefits from being a better communicator. In contrast, this paper argues that language emerged during a coevolutionary struggle between parental genomes via genomic imprinting, which is differential gene expression depending on parental origin of the genetic element. It is hypothesized that relatedness asymmetries differentially selected for patrigene-caused language phenotypes (e.g., signals of need) to extract resources from mother early in child development and matrigene-caused language phenotypes (e.g.,  socially transmitted norms) to influence degree of cooperativeness  among kin later in development. Unlike previous theories for language evolution, parental antagonism theory generates testable predictions at the proximate (e.g., neurocognitive areas important for social transmission and language capacities), ontogenetic (e.g., the function of language at different points of development), ultimate (e.g., inclusive fitness), and phylogenetic levels (e.g., the spread of maternally derived brain components in mammals, particularly in the hominin lineage), thus making human capacities for culture more tractable than previously thought.

Brown, W.M. (2011). The parental antagonism theory of language evolution: Preliminary evidence for the proposal. Human Biology, 83 (2)

The path to empathy

Published online at Plos one yesterday a study done at the Yerkes National Primate Research Center by Campbell and de Waal (2011) has found a link between social groups and empathy in chimpanzees as demonstrated by involuntary yawning responses.

The study is based on the psychological concept of ingroups and outgroups. In humans ingroups are those we see as similar to ourselves and outgroups are those we perceive as different.

Biases involved in ingroup-outgroup discrimination in know to even extend to involuntary responses which includes empathy for pain. This has never been tested in other animals though.

Contagious yawning is thought to be linked with empathy. The study used this assumption to test if chimpanzees’ ingroup-outgroup biases would effect how contagious a yawn can be. In other words if contagious yawning is linking to empathy and empathy is linked to ingroup-outgroup biases within chimpanzees then the chimpanzees should yawn more in response to watching ingroup members yawn than outgroup.

The study used 23 chimpanzees from two separate groups and they were made to watch videos of familiar and unfamiliar individuals yawning. Videos of the same chimps not yawning were also used for control. The chimpanzees yawned more when watching the familiar yawns than the familiar control or the unfamiliar yawns, demonstrating an ingroup-outgroup bias in contagious yawning.

The authors have suggested that these result may be more magnified in chimpanzees than it is in humans as chimpanzees live in much smaller communities than humans and are generally very hostile to those outside of their small social group. Ingroup-outgroup biases are therefore probably much more absolute in chimpanzees.

This study adds empirical evidence to suggest that contagious yawning is subject to empathy. This may have further implications for studying the evolutionary foundations of empathy which obviously has implications for things like theory of mind which is pretty high up on the list for preadaptations for language.

References

Campbell MW, de Waal FBM (2011) Ingroup-Outgroup Bias in Contagious Yawning by Chimpanzees Supports Link to Empathy. PLoS ONE 6(4): e18283. doi:10.1371/journal.pone.0018283

The adaptive value of age, co-operation (and secret signals)

More elephant based news!

A new study from the Proceedings of the Royal Society B, published today, has found that elephants pay attention to the oldest female elephant in their group when a predator is approaching.

The research, carried out in Kenya, used recordings of roars from both male and female lions and monitored the reactions of groups of African Elephants. It has been known for a long time that elephants social groups are formed around a matriarchy. The experiment found that groups of elephants with matriarchs quickly organised themselves into defensive bunch formations after appearing to stop and pay attention to their female leader. These groups were also much more likely to approach the loud speaker producing the roar in an aggressive manner.

Male lions present a greater threat to groups of elephants as they are much more likely to attack elephants when alone and are usually much more successful than females who will only attack when part of a group. The elephants showed an ability to differentiate between male and female lions. The study also showed that matriarchs who were much older were much more likely to react in the appropriate way to roars made by male lions which is thought to be the result of experience.

The signals which allow the Matriarch to elicit this co-ordination among her group are still largely unknown due to the lack of loud vocalisations and Karen McComb and Graeme Shannon, who lead the initial study, are now looking into finding quieter, less obvious vocalisations and posture cues.

The study provides the first empirical evidence that within a social group, individuals may gain benefits from paying attention to an older leader because of their abilities in making decisions when under threat. This generates insights into selection for longevity in cognitively advanced social mammals.

Out of (Southern??) Africa

It is a largely unchallenged claim of anthropologists that the human race emerged from the continent of Africa. However, claims relating to our evolution before our nomadic ancestors left the land of our origin have been left largely abstruse.

A new paper published on PNAS.org this week attempts to address this very problem through genetic analysis of several hunter gatherer societies in Africa including speakers of the nearly distinct N|u language. This was done because hunter-gather populations remain divergent in their variations at a level which is no longer maintained in the African population as a whole.

580,000 Single-nucleotide polymorphisms (SNPs) were analysed to calculate genetic relationships and diversity between the groups and propose possible evolutionary paths and branches.

Henn et al. (2011) propose that the genetics of those groups found in the south of Africa are the most diverse, and therefore the oldest, of any diversity found among other modern humans. This has caused them to suggest that the origins of modern humans may in fact be in southern Africa as opposed to the much more accepted view which is that we emerged from the east of Africa.

This assumed eastern viewpoint is a result of the earliest modern human skulls being found in the east and also the fact that humans in the rest of the world all carry a subset of genes found specifically in eastern Africa. However, until now, the populations represented in the study by Henn et al. (2011) have not been represented in previous genetic studies when making estimates of the whereabouts of our evolutionary origins.

Some dispute has arisen regarding these conclusions because the current whereabouts of these hunter-gatherer populations within Africa is not evidence to suggest that this is always where these populations have resided. These groups may have moved about and migrated from their original place of origin just as the rest of humanity has. Henn has retorted that, though this is a possibility, typically only a subset of a group moves to a new area, and this subset is less genetically diverse than the parent population. This would mean that if a group of humans left eastern African for southern Africa they would be expected to be less diverse in the population who moved and this contradicts the genetic data found in Henn et al. (2011).

References

Henn, B. et al. (2011) Proc. Natl Acad. Sci. USA doi:10.1073/pnas.1017511108

Elephants give each other a helping trunk

A study published on PNAS.org yesterday has shown that elephants might have shared goals which gives them the ability to co-operate.

An experiment was done using the classical 1930s cooperation paradigm used to test the co-operative abilities of monkeys and apes. This paradigm is used to explore the cognition underlying coordination toward a shared goal. This explores what animals know or learn about the benefits of cooperation and also tests their ability to comprehend a partner’s role in cooperation.

The experiment comprises of 2 animals who need to work together to pull 2 ends of the same rope in order to pull a platform towards them which holds a reward such as food.

Experiments such as this have never been done on animals apart from primates before. Plotnik et al. (2011) subjected this experimental paradigm to elephants and have shown that elephants can learn to coordinate with a partner. The elephants also delayed pulling he rope for up to 45 seconds if the arrival of their partner was delayed which showed that they comprehended that there was no point to pulling on the rope if their partner lacked access to the rope. The elephants learnt that this was the case much more quickly than has been shown in Chimpanzees in other studies.

Observations from the wild suggest that in nonhuman primates these co-operative abilities exist but experimental results have been mixed. Plotnik et al. (2011) claim that convergent evolution may have lead elephants to have reached a level of cooperative skill equal to that of chimpanzees.

You can see a video of the elephants doing the experiment here: http://news.bbc.co.uk/earth/hi/earth_news/newsid_9417000/9417308.stm

References

Plotnik, J. M., R. Lair, w. Suphachoksahakun & F. B. M. de Waal (2011)
Elephants know when they need a helping trunk in a cooperative task. PNAS 2011 : 1101765108v1-201101765.

Wampanoag film

 

A new documentary has been made about the resurrection of the Wampanoag language which has a few screenings coming up next month in the US. DVD’s are also available and details of both can be found here.

The story begins in 1994 when Jessie Little Doe, an intrepid, thirty-something Wampanoag social worker, began having recurring dreams: familiar-looking people from another time addressing her in an incomprehensible language. Jessie was perplexed and a little annoyed– why couldn’t they speak English? Later, she realized they were speaking Wampanoag, a language no one had used for more than a century. These events

sent her and members of the Aquinnah and Mashpee Wampanaog communities on an odyssey that would uncover hundreds of documents written in their language, lead Jessie to a Masters in Linguistics at MIT, and result in something that had never been done before – bringing a language alive again in an American Indian community after many generations with no Native speakers.

WE STILL LIVE HERE: As Nutayunean clip

Although I haven’t seen the film it sounds to be very much in the same vein as “the linguists” which came out in 2008. The Linguists follows two field linguists as they travel to document and help promote the rescue of near-extinct languages.

Documenting and reviving languages is an important thing to do as it increases our understanding of language. Every time a language dies we lose data which can inform us on the interactions between cognitive constraints and culture. A language dies every 14 days. Bearing that in mind, here’s a few links if you’re interested in this stuff:

SAIVUS (Society to Advance Indigenous Vernaculars of the United States): http://www.saivus.org/

Wampanoag Language Reclamation Project: http://wlrp.org/

Enduring voices: http://travel.nationalgeographic.com/travel/enduring-voices/

And a whole bunch of other links here: http://www.saivus.org/saivuslinks.html

 

The Quill to Communicate?

New footage has been filmed of a little known animal called the Streaked Tenrec in Madagascar. The footage shows the creatures can rub their quills together to make ultrasound calls and can also produce tongue clicks  to each other which are outside of the range of human hearing.  Because of the ultra sonic nature of these sounds, it has been unknown quite to the extent that these creatures can do this, before now.

The BBC, who’s film crew for the new ‘Madagascar’ series filmed the animals, states in their article about the new findings:

Using the bat detector, the filmmakers found that the seemingly “quiet” mammals were constantly communicating.

and

Few studies have been made to investigate why streaked tenrecs communicate both vocally and via their quills but they are currently the only mammals known to do so.

This may be a classic misuse of the word ‘communicate’ in that just because an animal is making a noise does not make that noise communicative. At no point in the article does it make any claim about what it might be that they are trying to communicate to each other and the only assertation that is made as to why the Tenrecs might be making ultrasonic noises is when the story goes on to state that scientists hypothesize that these ultrasonic sounds are being used as echo location and so to call these sounds communication is the same as calling our ability to see where we’re going communicative (it’s not).

Not to completely discredit the premise of the story by the BBC, the behaviour of producing the ultrasonic sounds using the quills could be a form of stridulation which is used by other animals to attract a mate, act as a warning signal or to protect territory. If this is the case it could be groundbreaking stuff as stridulation has never been seen before in mammals. But until the production of sound can be seen to manipulate the behaviour of others it seems ‘communication’ may be too strong of a word.