Category: Science

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.

The Biology of the Language Faculty: Its perfection, past and future

Just came across these videos of Noam Chomsky via the Linguistics Blog:

The Biology of the Language Faculty: Its Perfection, Past and Future by Noam Chomsky (1/4) from Joe Zavala on Vimeo.

 

The Biology of the Language Faculty: Its Perfection, Past and Future by Noam Chomsky (2/4) from Joe Zavala on Vimeo.

 

The Biology of the Language Faculty: Its Perfection, Past and Future by Noam Chomsky (3/4) from Joe Zavala on Vimeo.

 

The Biology of the Language Faculty: Its Perfection, Past and Future by Noam Chomsky (4/4) from Joe Zavala on Vimeo.

I haven’t had chance to watch these yet, and I’m not sure when I’ll next get a chance, but I’ll try and come back to this over the next few days.

Imitation and Social Cognition (III): Man’s best friend

In my two previous posts (here and here) about imitation and social cognition I wrote about experiments which showed that
1)  young children tend to imitate both the necessary as well as the unnecessary actions when shown how to get at a reward, whereas wild chimpanzees only imitate the necessary actions.
And that
2) both 14-month old human infants as well as enculturated, human raised-chimpanzees tend to ‘imitate rationally.’ That is, they tend to be able to differentiate whether an agent chose a specific way of performing an action intentionally, or whether the agent was forced to performing the action in this specific manner by some constraint.
ResearchBlogging.orgIt can be argued that these experiments demonstrate that human infants and young children show an early sensitivity to the communicative intentions of others. That is, they seem to be able to infer that a demonstrator’s specific (and ‘odd’ ) actions are somehow relevant, because she chose this specific manner freely (see also these two extremely interesting posts by the philosopher Pierre Jacob, on which my own post is partly based)

The fact that human-raised chimpanzees also show this sensitivity suggests that enculturation plays an important part in this process.
In a very interesting study, Range et al. (2007) used an experimental setup similar to that of Gergely et al. (2002) (which i described in my second post, here) to test whether other ‘enculturated’ and domesticated animals show the same kind of sensitivity: dogs.

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.

Bipedalism: New Fossil Evidence and Language Evolution

Published in Science today, 11.02.2011 (yey! palidromic date!) is a report on the find of a Complete Fourth Metatarsal and Arches in the Foot of Australopithecus afarensis.

New fossil evidence from Hadar, Ethiopia suggests that our ancestors from 3.2 million years ago (Australopithecus afarensis (better known as Lucy)) had arches in their feet.

Arched feet are an essential part of the bipedal way that modern humans walk.

Although the skeleton of Lucy was found in 1974, until now important foot bones in all of the specimens uncovered to date have made it difficult for researchers to understand precisely how well adapted for bipedalism a. afarensis were.

Why should people interested in Language Evolution care about bipedalism? Well, here’s some food for thought:

1) Bipedalism likely had an impact on our cognitive abilities. As climbing as a form of locomotion became less common, different ways to cognitively represent space and distance probably had to be found. These new systems could have involved imitation (mirror neuron alarm bells start ringing). By adding imitative abilities to already existing spacial awareness that are seen in modern, non-human primates, this may have created mechanisms which allowed hominins to visualise themselves walking across plains (McWhinney 2005). This may have been the original selective pressure for imitative ability and therefore could have some implications for the imitative abilities which exist within language.

2) Upright posture would free up forelimbs which may have had communicative advantages as it would free the hands up for gesture. This theory has been somewhat rubished in that  the first apes to adapt a bipedal posture were probably cognitively not much different from today’s apes (assumed from evidence of skull size). However even if this was not the selective pressure FOR bipedalism it doesn’t stop it being relevant to the discussion.

3) Free hand movement would also lead to making tools. Stone tools getting more complex and language developing as evolution took place may show a close relationship between enhanced motor movement and language. Deficits in motor control are also often linked to aphasia so there is a strong connection between manual activity and speech communication.

4) When Chimpanzees and Gorillas are socializing in groups they go from a ‘knuckle walk’ to sitting in circles, this allows apes to keep eye contact with each other in social situations,  bipedalism would also allow one to keep eye contact at all times, even when in motion, and so the this may have been a selective pressure. Stanford (2003)

5) Evolution of the cortico-striatal neural circuits (basal ganglia) that regulate human language may have been shaped by the demands of upright bipedal locomotion. (Lieberman, 2001)

A lot of this debate is quite controversial but I thought I’d put some thoughts/theories out there in celebration of exciting new finds!

References

Lieberman, P. (2001) On the subcortical bases of the evolution of language. In Jurgan Trabant and Sean Ward, editors, New Essays on the Origins of Language, pages 21–40. Berlin-New York:Mouton de Gruyter.

McWhinney, B. (2005) Language Evolution and Human Development. In Bjorklund, D. and Pellegrini, A. (Eds.). Origins of the Social Mind: Evolutionary Psychology and Child Development (pp 383-410). New York: Guilford Press.

Stanford, C. B. (2003). Upright: The evolutionary key to becoming human. New York: Houghton Mifflin

Ward, C. V., W. H. Kimbel & D. C. Johanson (2011) Complete Fourth Metatarsal and Arches in the Foot of Australopithecus afarensis. Science: 331 (6018), 750-753.