 Okay, welcome everyone to this SOAS Linguistics webinar. My name is Joey Love-Strand. I'm a postdoctoral fellow at SOAS. Our speaker for today's webinar is Cecilia Pidi Iglesias, who is a PhD candidate and researcher in the Hunter-Gatherer Evolutionary Ecology Group at the University of Zurich. She's here today to talk about work in which she brings a quantitative modeling approach to the study of language change. Focusing on recent publication and other work on the language, changes in language use among speakers of Yucatec Maya. Particularly this relates to a recently published paper called Changing Language and Put Following Market Integration in a Yucatec Mayan Community. And I'll put a link to that paper for those of you here in Zoom to have that as a reference as well. Even though this research is in the Americas and outside of our geographic focus at SOAS, the insights from this line of research do have implications for minoritized language communities all over the world and I think is relevant to a lot of the things we focus on as SOAS linguistics. So Cecilia will give us a talk for about 30 or 40 minutes and then whatever time is remaining in the hour together we'll take questions and have some discussion with participants. So Cecilia, thank you for agreeing to come and share your research with us and we look forward to hearing what you have to share. Thank you. I'm gonna share my screen and the first thing that I will ask is for you to indicate whether I'm sharing the right or the wrong screen. And okay, which screen can you see? Wrong one? The wrong one. Okay, that should be it. Yep, there we go. Okay, let me sort everything out. Okay, so thanks a lot again for inviting me and yeah, perhaps you already mentioned a bit in the introduction but to contextualize a bit my approach to the study of language. I am an evolutionary anthropologist so I guess I focus on sort of evolutionary accounts for language use or language change and that's how I think about the topic. I actually study at UCL. So I've been many, many times to sow us and to the sow us by when I was a student. So it's a place that I really like and I've been to previous seminars in linguistics when I was a student. Yes, today I'm gonna talk about the work that I did a bit for my master's thesis in the Yucatan Peninsula. Looking at people, at how people in indigenous communities or in general in people in communities that are undergoing rapid socioeconomic changes may change the way in which they use and think about languages in order to adapt to such changes. And this is part of a broader project that I started a few years ago looking at how families and communities adapt in general their socialization practices so not just language use. So we're looking at broader childcare patterns or interpersonal interactions and I'm more than happy to talk about this in the question session if we don't have time to go beyond language probably during the talk. And as you perhaps mentioned, I do think that languages are just one of many more human cultural traits and Mexico is just one example of communities that are undergoing sort of similar processes around the world. So I really hope that some of the insights that I will bring or that I hope to bring can be generalized beyond Mexico and perhaps beyond language. I will ask that people do not make public and I know that it will be recorded those slides that have like sort of cross Twitter birds because it's stuff that is currently under review. So I shouldn't make that too public. So I guess I'll start by saying that sort of the uniqueness of human language or the way in which humans use language is one of those things that's fascinating research from every field and not just in the social sciences but also in biology. And it's for a good reason because obviously everything that we do from learning, thinking or building culture depends on language. And that's why perhaps in an over simplistic view people such as Steven Pinker or just many other biologists have assumed that given that we are a linguistic species and the way that we use and think about language there must be an evolved and a universal and distinctive human trait. But I think rather than blindly trusting people like Steven Pinker it is perhaps a better idea to question such bold claims and in general I am sort of a big advocate of questioning anything that claims human universality and anything. So what I'm gonna do in this talk is I hope to provide you with some tests of these assumption with regards to language use and thinking about language. As an evolutionary anthropologist when people talk about the universality of human language I think a good place to start for me is by acknowledging that humans are probably unique in the animal world in that we organize ourselves around symbolically marked cultural groups that we anthropologists called ethnic groups but this has nothing to do with biology but simply means groups whose members share norms, expectations, skills and beliefs and that coordinate with one another. And these cultural groups we know that they are the main source of variation between human populations. We know that for example, genetically we are a very, very similar species like any two chimpanzees from two different groups would be much more similar than two humans living in opposite ends of the planet. So given that one of the key features of these sort of ethnic or cultural groups is languages I just want to look at the role of languages in allowing humans to live in this uniquely structured land, culturally structured landscapes. So I guess my take is that what I want to argue is that in order to understand why humans have language at all we need to understand why we have seven, around 7,000 of them. And precisely, precisely because people from the same cultural group require common codes of communication or languages to coordinate and interact with one another researchers have proposed that linguistic variation may have played a primary role through our revolution in creating, preserving and signaling such variation between human populations. This is because on the one hand by limiting between group communication because people from different language groups who don't understand each other this would restrict the diffusion of culture between different groups and therefore like sort of help sustain cultural diversity at the sort of like meta-population level. At the same time, those landscapes emerging from a culturally structured and linguistically bound world would have shapes or psychology. So the idea is that we would have evolved to use languages as a predictor of other people's ethnic category membership which in turn could lead to for example displaying a preference for same language speakers that as that would avoid like coordination costs when interacting with other group members. And linguists and psycholinguists have done experiments and there is some like tentative evidence for example with US infants that they found that they as early as five months they already show like a looking preference for same language speakers. And by 10 months they prefer to be friend or to exchange toys with people that speak the same language as opposed to people that speak a different language. However, the universality of these language boundaries to structure social behaviors or cooperative partnerships has become increasingly disputed because as we do more cross-cultural research we realize that there are many ethnic groups around the world that are linguists, heterogeneous and that the US picture where like you have a massive amount of people just speaking the same language and only that language is a bit of a bizarre situation around the world. And this picture I really like because it's a painting by Amar to Elder from the Western desert in Australia is a hunter-gatherer population and their society is organized in states and the painting represents the state where the man lives and one can belong to a state through initiation all through their lives. One can belong to multiple states but the interesting thing is that states are all linguistically heterogeneous. So people in the same state don't speak the same language at all. So why I put this picture is I presumably like and we have evidence that these state-based societies have been going on in the Western desert for a while in such a landscape, it would really not pay off to use language category membership as predictive of anything in your social world. And so that's why I think investigating under what conditions an individual linguistic repertoire distinguishes their social behavior is really necessary in order to understand the consequences of acquiring competencies in one or more languages especially when these landscapes do change. And I think this is sort of like a bit of a timely research because currently there are rapid socioeconomic changes happening all over the world whereby many previously subsystems-based communities are becoming increasingly exposed to global and economic systems and educational systems that involve becoming in contact with majority languages. And at the same time we're seeing that alongside these socioeconomic changes that we have a massive linguistic mass extinction going on and there's been predictions that by 2030 or something that around half of the world's languages will be extinct. And we know that most of these languages become extinct due to language shift. And often these language shift is attributed to these processes of market integration leading to a devaluation of the indigenous languages spoken in these communities by its members who decide instead to adopt the majority language because it's seen as having a higher status. However, before we started working on this a few years ago we found that there were very few studies that had quantified how or such linguistic erosion was taking place. So we don't know exactly what social and economic factors may drive individual decision making about language learning use and transmission and how those factors may change following market integration. And I think this understanding these mechanisms is really important in order to predict the fate of linguistic landscapes. So we said to study some of these issues and as I said in the Yucatan Peninsula and of course, like Mexico is a great place to study anything to do with linguistic diversity because it's one of the most linguistically diverse places that one can imagine. And within Mexico, Yucatec Mayan which I will refer to as Mayan from now on is the second most spoken indigenous language that has approximately like 750,000 speakers. And we know that the speakers of this family of languages come from like sedentary students, I would call Turalist and Migrates to the Yucatan Peninsula around 1400 BC. So we know that kind of like the Mayan way of life is pretty remarkable because to this day and traditionally most Yucatec Mayan families still live of subsistence males farming. They still live in a system where like households are the main unit of production and consumption. And at the same time, there is this institutionalized land tenure system called the HIDO system that grants communities a collective ownership of agricultural lands, which means that this cannot be sold or inherited so that all community members have access to food, firewood and other resources. And also it means that there is little inequality between families living in the same community. However, starting in the nineties, there were a lot of rapid socioeconomic changes started unfolding in the region, mainly because there were a lot of roads being built and there was a development of the tourism sector in Cancun and the Riviera Maya. So men started participating in wage labor in urban centers, which meant that families started to getting access to like new farming methods on market goods from these urban centers. At the same time, education in Spanish started becoming more available. In theory, at the moment, there is like a 30-70 system whereby 70% of classes should be in Spanish and 30% in Yucatec Maya. But nowadays the reality is that, and I've talked to other researchers working in this area that like 100% of the classes and the textbooks are in Spanish. However, whilst we've seen massive changes in this region, at the same time, there are other aspects of community and family life that have remained very, very stable. As I said, the household and residential structures have remained pretty constant throughout this period. Wage labor, in most cases, supplements agricultural returns rather than being a replacement for it and only is practicing times of need. So for example, if there are several sons in a household that are over the age of 15, only one participates in wage labor whilst the other maintains the families agricultural land. So in this context, sort of I wanted to ask three main questions. The first one is whether these rapid socioeconomic changes have led to changes that are strategic in the way in which people use and transmit languages. If so, whether it has also changed the way in which people reason about ethnolinguistic identity and in order to adapt to these changing linguistic landscapes. And the third one is like, what can these tell us about the sustainability of linguistic diversity in the region? So the first study that I want to present is kind of the answer or an attempt to answer that first question and is to try to look at whether changes, whether market integration have led to changes in the way people use and transmit languages. So to look at this, what we did was to compare the linguistic input received by infants that were 16 to 24 months old and that grew up in the same communities, but in two cohorts that were like six years apart. And these two cohorts were very different in terms of the socioeconomic profile of the villages. As for example, in the first cohort, people could only complete primary education in the natal village and in the second cohort, they could all complete like secondary education and all in Spanish. Primary school attendance of the caregivers in the second cohort had also doubled as had their involvement in wage labor and their access to market goods. However, there were, as I said before, other aspects in the village that had not changed throughout this time period. Family sizes had remained stable. So each woman has around six to eight kids, which means that the recorded children had an average three to four older siblings. And age at first birth had also remained stable. So this was kind of like nice in terms of, to rely on a natural experiment because we basically could see or could conclude that any changes in linguistic input were not simply due to changes in the demographic structure of the villages. To quantify these changes or potential changes in linguistic input, what we did was to obtain video data of these infants in their home environments and code it for each utterance, the interlocutor and whether the impact was being directly addressed by them or not. And this is important because many cross-cultural studies have claimed that children from like non-Western societies, to say it in a way, receive a lot less directed input from their caregivers. So we wanted to see whether that was the case and we know that directed input is also important for language learning. So the first thing that we assessed was whether the number and type of audiences received by infants had changed throughout the two cohorts. And what you see in this diagram is what's called sort of posterior probability distributions of some Bayesian models, but basically the red vertical line is no effect and the peak of the little colored mountains is the mean difference between cohorts in the number of entrances of each type that children receive. So contrary to the expectation that market integration would lead to more directed input because non-Western societies would start resembling those majority cultures more, what we see is that the mean number of entrances per hour that are being directed to children decreased a lot from 2007 to 2014. And this means we came in the form of less utterances from other children. This may be because children were not around because children were like focused on education and therefore taking, adopting less the role of caregivers of other children. This is something that we are investigating now. However, we didn't see big changes in the number of overheard utterances received by children, which means that this is probably not the product of like less people being around to say it in a way. Nonetheless, still most utterances that children received originated from other children and this was around 70%. But I guess the important question for today is is this trend the same for both languages, for Spanish and for Yucatec Maya? So this is the next thing that we looked at. And the short story is no, we figured another set of models to see if the proportion of input in Spanish versus Mayan that infants received in child directed overheard and in the overall linguistic input had changed across cohorts. And we saw that the mean total number of utterances that children received in Spanish had nearly doubled across cohorts. And this was the case for directed input and this is what was driving the overall trend. There was no difference in the overheard input if anything a decrease that children were receiving in Spanish across cohorts. This means that caregivers were altering the proportion of Spanish they use when directing speech to infants but not when generally speaking to other community members. As a result though, the mean number of directed utterances in Mayan that these kids from the second cohort were receiving was a lot less than those from the first cohort. Again, this trend was not the results of a different availability of carers because all carers and we broke down which is not shown here, but we broke down the analysis as well by caregiver type. All caregivers, regardless of if that was primary caregivers other adults or children use Spanish in the speech that they actively directed to infants but primarily use Mayan in the speech that they use with one another and hence that those infants overheard. Nonetheless, the majority of the input that infants were exposed to in general was still in Mucotec Mayan. So again, this indicates that there has not been a generalized process of language shift in the village. So obviously then we started thinking about potential reasons why caregivers were decreasing the amount of Mayan that they were directed to infants. And what we did was in 2009, we interviewed 126 adults from these communities including all of the primary caregivers from the two cohort samples. And we basically asked them, I mean, we gave them extensive service but then we asked them if they thought it was more important to learn Maya or Spanish and as a follow-up question why they thought each language was important to learn. However, when all of the adults that we interviewed responded that learning Maya and Spanish were equally important. So they didn't devalue Yucatec Mayan. However, when we asked them why they thought each of those languages was important they gave us completely different answers. Mostly they told us that Mayan was regarded as important for maintaining social relationships and cultural ties within the village and that Spanish was seen as a more functional tool to access necessities such as communicating with doctors going on shopping trips or being able to work in nearby urban centers. I'll get more into these reasons sort of in the following days set because we actually explored some of these issues but I guess these results raised two questions. As I said, if parents are not trying to shift input away and they value both languages equally why is it that they are directing less input in Mayan to young children and changing the strategies that we're using? And the second one is are they doing this strategically but for some other reason? So one of the options that we explored was saying okay maybe it's not beliefs about the relative importance of the languages but about the relative ease of acquiring them. And we know that in many sort of small-scale communities development is thought to come from within the child and therefore that not too much active instruction is required in order to learn anything. So it may be that caregivers believe that language is sort of learned automatically and it is potentially the case that in emerging bilingual contexts where adults and older children are more likely to have learned the non-local language later in life that they might have encountered difficulty in learning this new language so that they think that they may lead them to reach the false conclusion that the non-local language is harder to learn. So potentially this believes that language learning in one of the languages is harder than in the other could be responsible for the observed trends. To investigate them we asked again the 126 interviewees. We told them that some people believe that language needs to be taught what others believe that language just comes out on our own and what do they believe? And as a follow-up questions we asked them whether they believe that that was the case for Maya and Spanish in the same way. In response to the first question around 70% of adults told us that they believe that language needed to be actively taught in order to be learned and there were no difference between cohorts in this response. However, in response to the second question around 50% of the interviewed adults believe that infants learn Spanish and you could take Maya differently. And specifically most of the interviewees thought that you could take Maya was easier to learn than Spanish and indeed sometimes they reported that Spanish required infants to be actively taught whilst Maya could be learned from overhearing. Therefore it might be that people were directing more input in Spanish because they believe Spanish was relatively more harder to learn even if they wanted the children to end up with equal competencies in both. So again, we tested this by seeing whether caregivers that held this belief that Spanish was harder to learn were the ones that were directing a higher proportion of input in Spanish to the children. And this is exactly what we found out. However, this was the case for both cohorts. It also did not explain the change in linguistic input across cohorts because there were no differences in the prevalence of this belief across the two cohorts. Yes. We also looked more and I sort of will skim through it because these are really preliminary findings. We basically looked whether individual characteristics of the children rather than of the languages themselves were also responsible for the amount of linguistic inputs that parents were directing them in Spanish. And here I will ask you to focus on the second plot which basically what shows is a number of variables that we tested whether they affected the proportion of directed utterances that primary caregivers were directing in Spanish to a particular infant. And as you can see what we found was that younger children sort of later born children were more likely than their older siblings to receive Spanish input by the primary caregivers in both cohorts. And this is controlling from maternal age. So it's not the children from older, from younger moms is like given the same age moms sort of the later born down the birth order. And I think this is an interesting finding and in this data set we didn't have too much data to look at it into it deeper, but I'll come back to it. However, sort of the hypothesis that we were considering is that given that mechanized farming has led to less work needed in the farm and at the same time you have these and a heath or land tenure systems whereby families cannot buy more land this translates into families needing less children in order to be covered for family either. So was this new market opportunities at the same time require particular linguistic skills like Spanish and substantial time away from the village that these sort of like Spanish input in later bonds is kind of the product of a sort of household level linguistic division of labor where families once they have enough sort of like children that speak Yucatec Mayan and that are integrate and that are sort of necessary for like working for farm labor. They sort of specialized in like making sure that the later born ones are like as best prepared as they can in order to engage in the market economy so that then they can pull resources back in the household and sort of benefit from these like best of both worlds strategy. Yeah. So to recap a bit what we've seen so far I have shown sort of like preliminary evidence that these newly available opportunities from market integration has led to different subsistence strategies that are like that pay off differently for different individuals and that since these different subsistence strategies that are associated with different languages this may mean that individuals obtain different payoffs from learning each of the languages available to them which again will lead to different choices in language socialization that will ultimately result in heterogeneity in the language use and in the language competences that we see in a particular community and that this has the potential to shape linguistic diversity and its fate. However, now remember at the start of the talk when I was talking about language and its functioning, creating, preserving and signaling cultural variation and this heterogeneity in language use and in language competences within communities may change sort of the clustering of cultural norms around particular linguistic boundaries or to say in different words it may change whether these like ethnic groups much linguistic groups. So in a way like this changes the way in which people should reason about the relationship between ethnic and linguistic identities and thus the kind of influences about others that they should make based on their linguistic repertoires and the kind of social behaviors that they should display to what same or different language speakers. But if we go back to the evolutionary anthropological literature, there's even people arguing that humans are not even able to do this because this is an instinctive and evolve human capacity. So in a way like whether humans were able to flexibly adapt the way in which they reason about the relationship between linguistic and ethnic identity following these socio-economic changes, some changes in language use is sort of the next stage of the things that we wanted to investigate. As I say, yeah, the reason why people have proposed that the way in which we reason about the linguistic between language and ethnic group membership to be universal is because of these ethnic landscapes being ancient. So it could be that we have evolved to use language as predictor of shared cultural affiliation. Some people have proposed a variant of this hypothesis, which is that since children tend to learn language from those individuals that are around them during the early phases of development, which is the time where language gets acquired, presumably that linguistic affiliation acts as a probabilistic batch of relatedness and therefore that people have evolved to use language as a cue of relatedness. However, under both accounts heterogeneous bilingualism should present a problem because if language is an important marker of social group membership, learning an extra language, so speaking two languages should introduce noise into this system or should be seen as someone's attempt to abandon one's ethnic affiliation in exchange for another or as trying to pretend to be someone that they are not. This means that potentially even acquired bilingual competencies could be something frowned upon within communities. And there are examples of this happening and there is a famous case in the Vau Pest based in Brazil where linguistic affiliation has been traditionally used to guide marriage patterns with explicit rules about who has the right to marry or not based on the language that they speak. And now that these communities are being exposed to Portuguese and to other languages, not only speaking other indigenous languages is frowned upon but those who learn Portuguese, the national language are seen as sort of people that try to be pretentious or better than their peers and has very negative effects in their access to sort of local social networks. So potentially there is sort of like a second alternative which is that human that it may be an evolved system but it may be that evolution has shaped a way of reasoning about it may be that evolution what has created is sort of like flexible developmental patterns that provided active placis de by means of allowing us to attune to the social landscapes in which we are raised. So it might be that people are able to adapt through development to the social landscapes in which they are raised. So I'm not trying to make a nature versus nurture distinction as both pathways would be the product of evolution because evolution can produce developmental processes that vary in adaptive ways in the terms of their flexibility. So to look at this and I will talk about this really fast what they did is again to this 126 adults that we interviewed we asked them on a scale of one to 10 how Mayan would they consider a person across scenarios one to age which basically vary in like how they acquired then you could take Mayan or Spanish how proficient they are on it on the language profile of their parents. And we fitted a series of models to assess how our Mayan identity was related to language competence and to the inheritance of this language competence. And what we found was that linguistic behavior was indeed used as a marker of ethnolinguistic identity because competence is in you could take Mayan. For example, if you compare A here where you could take Mayan speaker only speaks you could take Mayan with G where someone had a you could take Mayan parents but didn't learn the language. Clearly language competence was associated with belonging to the Mayan ethnolinguistic or ethnic category. However, the Mayan ethnolinguistic identity was not seen as incompatible with acquiring competence in Spanish because indeed Spanish Mayan bilinguals were rated higher in Mayan identity as Mayan monolinguals. At the same time, linguistic identity was not seen as heritable as children from Mayan parents was not considered as having a Mayan ethnic identity if they didn't speak the language. So we don't find evidence to support this claim that humans have evolved to use linguistic boundaries as signals of biological descent. As I said, ethnolinguistic identity was seen as flexible and not stable through life because you could become something else if you married a Mayan person and then learn Mayan then you would become Mayan even if you weren't so before. And interestingly, we also saw that like in the individual's own language competence and this is the pink versus the blue bars also influenced this rating. And in particular, Mayan monolinguals gave bilinguals a higher rating in the Mayan identities of those individuals that could only speak Mayan. So both the raters and the rated personal attributes determined a lot how you would be perceived by members of your community. And I think I will skip the next two slides because they basically talk about the relative strength of language versus other potentially culturally salient traits in sort of guiding these heuristics. And this is work that is ongoing and that we are also comparing with another context in Peru. We are doing some comparative work in the Perugian Altiplano with some communities that speak Quechua and Aymara that are also integrating market economies and being exposed to Spanish. But basically what we find so far is that there is this sort of flexible way in which humans think and reason about language following market integration. So it really indicates that we are a lot more developmentally plastic than a lot of evolutionary anthropologists like to think. And the reason why I skip this part is because I want to sort of move my attention to an actual quantification of these patterns. Because so far we have shown heterogeneity and flexibility in the way people use, transmit and may think about languages, but we have not tested really whether different language behaviors lead to actual different social or economic payoffs. And we have also not seen how does the way in which people reason about ethnolinguistic categories actually relate to the social behaviors people display towards one another based on the language they speak. And therefore whether language behavior does actually translate into different sort of access to social networks or community networks. So I'm, oh. This is weird. I was like my screen is showing something different than the other screen. So I'm gonna present now results from sort of some communities that are like further down the road were the ones that were that would sort of tackle in the previous study. And this is some communities where Karen Trammer my collaborator has been working since the early 90s. And it's an amazing opportunity because she has been collating data on every inhabitant in the village for like over like 30 years now. And social networks of exchange of help, visits and cash. In these villages prior to 2000 all individuals lived only from growing maize and the village was completely isolated. And again, after 2000 a lot of economic development began when a paved road which built with facilitated access to new farming methods and the transporting of crops to market, children to school and people to wage labor jobs. Again, these changes have expanded the ways in which people and household made their living the amount of schooling children receive as well as the exposure to Spanish that inhabitants are receiving. So first I will talk about our investigation on how changing livelihood opportunities are associated with a change in the use of indigenous and majority languages and whether individual economic returns vary across individuals with different language competencies. And then I will turn to some work using sort of in-depth social network analysis to actually evaluate the social outcomes of speakers with different linguistic repertoires. And in doing so, I want to shed a bit more light on the extent to which social and economic factors may shape the long-term coexistence of indigenous and majority languages in these communities. So first sort of as a sanity check we checked the changes in the number of Spanish speakers across the year. So from 1992 to 2017. And we saw again that this is only people over six years old that the number of Spanish speakers had basically had basically doubled across cohorts. Still in the second cohort, there were no Spanish monolinguals which means that we have not seen a language shift or at least evidence for language shift so far. Then we turn into the predictors into investigating what predicted whether an individual would speak Spanish or not. And there seems to be a strong relationship between speaking Spanish and the participation of households in the new market opportunities. As households that participated in a committed wage labor strategy that meant where the mayor, head of household was exclusively a wage labor. The individuals born into this household were much more likely to speak Spanish than not. Obviously education was also a big predictor. And again, younger individuals from large families so later borns just like in our previous study were much more likely controlling from maternal age than their older siblings to be Spanish speakers. Again, living in a large family may mean that other siblings are available to work in agriculture. So as a later born, you might be better off working in wage labor because you may simply have not enough land or there may not be returns for you to work in the agricultural field. Is this true? In this dataset, we could actually test this because we could not only test the predictors of speaking Spanish, but as you can see this plot indicates the predictors of participating in wage labor. And again, speaking Spanish was the strongest predictor of whether an individual would participate in wage labor or not. And as this bar in the bottom shows, again, later born individuals from large families were much more likely than their older siblings to be wage laborers. Then we wanted to ask, okay, do households that managed to diversify their subsistence that is to engage in a mixed economy by having some members participate in wage labor and others to give in agriculture, are they better off than those families that failed to do this? So then we fitted some more models to see whether household economic strategies really predicted the net income that households were getting. And we found that although the number of hectares and the cultivation that households had did not predict the net income, having a male head of households who engage in wage labor did increase households net income. In addition, was having a Spanish speaking female head of household did not increase household net income, having a male head of households that did speak Spanish did increase net income. And I will sort of look into the gender differences in the next slide, so I won't get too much into this, but it does suggest that being able to have at least some individuals in your household that speak Spanish and engage in wage labor and sort of adds this extra dimension to households economy does increase their socioeconomic outcomes. Okay. So then after evaluating the sort of economic impact of language and subsistence strategies, we turn into evaluating the social network outcomes of individuals with different linguistic repertoires. And also this allowed us to evaluate whether same language speakers were preferentially associated with one another. For this, we had ego-centered social networks drawn by the female heads of households in 2007 on behalf of all household members. And we have household level outcomes, network outcomes, because we thought that's what made more sense given that the households have the unit of production and consumption. And we have three types of networks. The first one is who in the village did the egos visit weekly. The second one is who in the village did egos help, had helped egos with childcare and food production. And the third one is who in the village would egos be willing to lend a sum of money equivalent to a weak salary, which is quite a lot of money. So in this first plot, you can see what's called associativity coefficients, which means the tendency of same language speakers to preferentially associate with one another. And the orange diamonds show the observed associativity coefficients whilst the box plot show the mean of null distributions generated across a thousand simulated networks with similar characteristics. And again, and the point that I am trying to make is that in line with results from the other field side we find that the way people use language, not just to make emphasis about other social characteristics but also to guide actual social behavior is strategic and network specific. For example, while speakers, but same language speakers were not more likely to visit each other, they were more likely to offer help to one another in domestic tasks. And this might be because for more costly cooperative actions, you may actually actively seek in group memberships as coordination failures, for example, are more costly. However, on the contrary, we see a negative associativity on language for the money-lending network, which means that my and monolinguals are more likely to receive cash loans from Spanish speakers and vice versa. And this makes sense because my and monolinguals are those individuals who are less likely to be engaged in a cash economy and therefore more likely to need cash loans from Spanish speakers. And at the same time, and this has also been observed in like the Simane in Bolivia and in some inner communities, those more market-integrated households tend to be more likely also to distribute their wealth because this means that working for wages, for example, means that adult men are away from their village for extended periods of time, which means that their households are more, perhaps in need to be able to access local networks of social support whilst several of their members are away. And therefore need to access and therefore lending cash to others may be a way of ensuring access to social capital. And for this, the nice thing about having the full networks in the village was that we could see whether the tendency of individuals to invest into local social networks varied according to their linguistic or socioeconomic characteristics. So for example, here we assess the predictors of the number of incoming and outgoing ties that households had in each of the networks based on their characteristics. And again, indeed similarly to the Simane or the Inuit examples we also found and this is not in the graph, that Mayer households whose members participated in wage labor did not decrease at all their investment into local social support networks. And both in absolute terms and in relative terms to the visiting network is translated into the fact that households with Spanish-speaking female heads and male heads could rely for help on a similar number of individuals from the village as those households whose female or male heads of household were monolingual in Mayer. However, again, the differences between the language-driven differences in access to local social networks were most pronounced in the new network that has resulted from market integration. And here we found that whilst households whose male heads of households could obtain more, speak Spanish, could obtain money loans from more individuals in the village, those households whose female heads spoke Spanish could borrow money from less people from the village. And this is despite the fact that their investment into networks of cash was not different. That is that people were equally willing to invest into this network in particular. Also, all of these females were domestic workers. So it doesn't mean that they were less time in the village and therefore less available in order to receive those cash loans. Therefore, I think this raises an important point because people have raised the point that linguistic affiliation may have an important role in maintaining group cohesion. But these results provides some empirical evidence that within a single community language use may have different social outcomes from different individuals within it. And what we think it's going on here but we need to look further into it is that given that Maya women spend more time than men in the village, they may have a central role in the building and consolidating local social relationships. And that this may contrast with men's primary role as breadwinners. Therefore, it may be that it's women who are responsible to sustain this traditional social networks and in particular the helping network where we saw that there was a positive assortment on language. And therefore, yeah, that's again since this language competence in Spanish at the same time are mostly acquired through education and work outside the village that monolingual women are those who remain in the village and who therefore had more opportunities to forge strong friendships with one another which this may be one of the factors that is explaining the fact that they are able those Maya language to obtain access to more people for cash loans because they may be those women that have in a way like a higher status within the village. So what does this second part of the talk or how does how might it inform our ability to predict the fate of linguistic diversity in this community? So long story short, in the second setting what we find is that over a 27 year period of socioeconomic changes, the emergent bilingualism that we have observed seems to be sustainable rather than transitionary because we're still not seeing even after sort of a full generation of many Spanish monolinguals. We have suggested that this might be because each language allows individuals, households and even entire communities to obtain a complimentary set of social and economic payoffs that may be particularly advantageous in market integrating and mixed economies. And I have also shown that whether individuals invest in learning each of these languages and the social behaviors that they may display towards one another based on their linguistic repertoire seem to be a flexible strategy to reap the those payoffs emerging from newly available socioeconomic landscapes. And I have argued that understanding the power of these socioeconomic changes to redefine this relationship between language and linguistic identity is important in order to assess the prospect of linguistic diversity because these payoffs are what determines whether people will keep using these languages or not. And that's it. I just want to thank everybody that has participated in this research both from Yucatan, from Cambridge and from Unam in Mexico. I thank all of you for listening. Thank you very much. That was great. We've got some time for questions. You can feel free to write your question in the chat. There's a couple of that we'll get to. You could also ask a question. You could signal that by using the right hand function or just writing in the chat that you want to ask a question and we'll get to you at some point. I just want to start off with a general background to this research program in the Yucatan Peninsula. Was this always set up as a longitudinal study or was somebody in 2007 first just looking at language acquisition attitudes that then it was added to? I'm just curious about how this was planned out and financed and organized over the years? No, I don't think initially it was planned as a longitudinal study. So, Lauda Schneidman, who is the person study working in the community, where I present this sort of the first set of findings, she did her PhD there looking at, she was doing her PhD in the US and she wanted to look at these sort of like cross-cultural differences in the amount of child directed speech or more generally child directed interactions. And since these recordings were available when I started doing my master's thesis, we started looking at whether there were differential language used as opposed to just changes in input patterns. And she's kept working in the community, so she keeps and we have another cohort now from like 2019, which we can see what's happening now. That's great. Another just detailed question about the program from Peter Austin. Yes, which language did you use to interview people about linguistic identity? So, I did all the interviews. So I'm Spanish, so I speak Spanish, but I did all the interviews with a friend and research assistant, Alex, who is from a Yucatec Mayan community. So how we went about it was we would be together all the time in everything and sort of like talk the women into and explain the tasks sort of half in Spanish, half in Yucatec Mayan, so that they could choose the language in which they wanted the interviews to be done. So it really, each person could choose whether they wanted to be interviewed fully in Yucatec Mayan or in Spanish. And can you sort of guess how often they responded using one language or the other in that context? I would say obviously there was a lot to do with age. A lot of the older women were more comfortable doing it in Yucatec Mayan. A lot of the input, like a lot of the women spoke perfect Spanish. Actually, I think most of them did it in Yucatec Mayan. A lot of women who like spoke Spanish really well were still happier to answer questions about like language identity in like Yucatec Mayan or would even switch halfway through the interview. So this happened very often that since, because I had also been living in the village for a while, that depending on like who were they directing or giving the explanation to that they would switch because they knew that I didn't speak Yucatec Mayan to talk to Alex or to me depending along the interview. OK. And then another specific question from Jonathan Kastin and this is about one of your charts here. So he asked about your data on CDS that you coded for either Mayan or Spanish across cohorts in terms of number of utterances. But did the quality of those utterances change at all? Was there more Spanish creeping in? Was there other structural change associated with the heightened prestige of Spanish in the linguistic market? I'm sure Jonathan can jump in to clarify if needed. Yeah, I don't know what he means by quality. If by quality means sort of the... Yeah, what do you mean exactly with the structure of the utterances themselves? Yeah, I mean, was there anything to suggest that, you know, that there was, I don't know, more code switching or more introduction, more Spanish-like structure into those utterances? I mean, you clearly tried to distinguish either Mayan or Spanish, right? I mean, was there any gray area or any evidence of that changing across the two cohorts? So initially, since the data was coded a while ago, initially what we did is that we coded, like we removed all the code switching utterances from, and an utterance is just like, it was like basically a clause, like anything that had like some hard and independent meaning. For structure, we didn't analyze the structure, the structurally the sentences, but one of the reviewers in the paper did ask us about code switching. So I went back to the data and look at like the overall prevalence of code switching in both cohorts and actually it was like almost not there. So it really wouldn't have impacted the analysis at all. I mean, there were like four or five codes with strategies out of like on average, like, you know, children receiving like 500 or 600 per hour. So it really wasn't very prevalent. Obviously there aren't- So you actually, you had to strip out very few codes which- Yeah, yeah, it was really like, okay, we can like strip them out in order to be fair in the coding, but like it really wouldn't make a difference. Okay, Mark, thank you. Great, so feel free to let us know if you have another question, you can raise your hand and put it in the chat. I wanna ask you what your thoughts are a bit more on the effect of education in this story because you talked about the parents feeling like Spanish is harder to learn. And I think you mentioned that all the schools are monolingual Spanish schools. So I'm wondering, you know, would you think there would be a significant change if this was a context where they had introduced mother tongue based multilingual education and the parents had the sense that when you send your kids to school, they can start in Mayan and they're gonna learn Spanish at school. It's not that we have to teach them Spanish in order to go to school. So if you had that kind of educational context set up, would you expect there to be a change in behavior sort of related to these attitudes around which language is harder to learn? For sure, yeah, I mean, I definitely think that that is the case. And we did see, I mean, and we do see, even if like there are differences in the amount of Spanish that different kids get, there is this belief that like, you know, we need to prepare them for school. The school is also like a social center. There is also like through school, they get a lot of like aid as well. So I know that they get blankets, they get access to a lot of stuff. So going to school is really something that's horrible and like everybody, like every kid is sent to school. So definitely like, if school was not in Spanish, I think the picture would look very different. It would be interesting to see if you could do similar studies in an area where they do have this kind of a program to see if there's any difference that correlates that. That would be a lot of work to set that up. Yeah, it's just that we started looking about it and looking for it. And we were looking at this school like indigenous education. But even the schools that are engaged because they've tried to promote multilingualism or I think that there's been some efforts, like there are scholarships that specifically ask people to like speak Yucatec Mayan. So this is another dimension of it because like speaking Yucatec Mayan actually like may help you paradoxically in your educational outcomes because especially for secondary and even post-secondary like university level, like these people could not afford to go to university elsewhere but like speaking Mayan actually helps them to get aid, to get educated, but then all that education happens in Spanish. So there's this, and we haven't found any, I mean, and we've looked but like we really haven't found any schools where like teachers are teaching and Yucatec Mayan beyond using the language just for class management. Okay. So it would have to be probably in another country, another context where somebody could... Yeah, or maybe somewhere else in Mexico. Yeah, yeah. I did have another question and I wonder, can you go back to the slide where you were talking about, I think it was your, maybe your last slide. Yeah, this one where you have this chart about payoffs. I think in here you're sort of talking really about sort of adult decision-making, I'm assuming in terms of what people sort of use their agencies to decide which languages to invest in and learn. I feel like this in a way is kind of a different story from the child directed speech story you were talking about earlier where the children don't really have a choice right in terms of what speech is directed at them and what they learn. And so there's a big difference in terms of whether your children come into this mixed economy already being bilingual or already or only having Mayan or only having Spanish because then the choice to opt into one of those languages is significantly different, right? If you come into this mixed economy only having one language or the other that just adds a layer of burden, right? To choosing, it makes that the payoff seem less though there's more cost to get that payoff. So I guess I'm just wondering, yeah, how do you see these as sort of these two stories being integrated? Because I think when you do integrate them it's still sort of a dismal story for preserving the use of indigenous languages in the long term. So I think the key way or the way in which I see it is through households because in a way like the languages that you're exposed to especially early in life are determined by like your household strategy. And that's why we quantified or we try to quantify payoffs at a household level because these decisions determine the decisions of your household and your household sort of socioeconomic profile is what's gonna determine which languages you learn and exactly how easy it is for you to reap the potential benefits when engaging in a market economy or not and so on. And we had when you were interviewing people a lot I mean, there are many cases and especially in them of older women who do not speak Spanish at all but that they were actively telling the young, they're sort of older kids to speak to the younger kids in Spanish because they need to learn Spanish even if they did themselves did not speak the language they were very much strategizing on like what was the language that they wanted their kids to learn and when. Would you ever expect to see you say if there's a change in awareness or an observation that there's a start towards language shift and families realize that we're losing the payoff of retaining my language and our family would you expect parents then to change their strategy and start to reinforce the use of Mayan in their home and in childhood speech because they want that payoff for their household? Yeah, I mean, and there are some specially men that were really worried about this like sort of you could take Mayan it's not as pure as it used to be I guess it's a belief that is prevalent like if any place but that we're very much like yeah, like wanting to sort of actively promote this but yeah, I suppose so far the only thing that we knew is that everybody thought it was important for them to learn so a lot of them were very reluctant to the idea and even when like we told them that we were studying like whether there were been a language change in language use whatever and explain them a little bit the research so like, oh my God, no, how is Mayan going to disappear like everybody speaks Mayan like you have to speak Mayan to live here So, good. Well, I'm looking forward to seeing these further papers come out as you explore this and the effects of Spanish both economically and socially in this context I think this is really interesting work and I think this is things that people talk about in very general terms very often in linguistic literature but to see it actually quantified and study I think it's really helpful. I don't know if there's any other talks a couple of people I mentioned that they're gonna have to go and just saying thank you for the talk there but we have reached the end of the hour so maybe we'll leave it there and just say thank you again to Cecilia for preparing this talk and for this research you're doing and yeah, good luck in your PhD research as well. Thank you.