1. Introduction

Heritage speakers (“HSs”) of a language are speakers who learnt that language in a naturalistic setting from early infancy and consistently spoke it at home, but who subsequently underwent extensive exposure to a different language, that of the wider society, and over time became dominant in it (Rothman 2009; Polinsky 2018a for an overview). Despite being native speakers of their heritage language (“HL”), however, HSs produce syntactic patterns that often diverge from those of monolingual and other bilingual speakers of the same variety. What causes this divergence is not completely clear, and while typological, cognitive, and language-specific factors have been considered in several studies, their relative weight in shaping change in HL is yet to be fully determined.

To assess the weight of these factors, HL studies have drawn on work on L2 or L3 acquisition or bilingualism. Regarding L2/L3, transfer (or borrowing, in typological terms) is one of the key concepts that has been examined, with considerable relevance attributed to the role of typological proximity, which is considered to be a main player in structural transfer by some (e.g. Rothman 2011), but not all (Westergaard 2019). Structural proximity has also been shown to play an important role in transfer, both in typological (Aikhenvald 2006) and theoretical (Montrul et al. 2011; a.o.) studies. Some stochastic models have been proposed for the relative weight of the languages in contact in the case of code-switching, which have highlighted the processing load of bilingual speech (Dijkstra & Van Heuven 1998) compared to monolingual speech (Dell 1986).

The study of code-switching, specifically, has brought to light several important factors that determine transfer and, in particular, the emergence of blends (Goldrick & Putnam & Schwarz 2016), i.e. linguistic structures that include elements from both languages. Note that some models of code-switching have been proposed that involve mainly grammatical factors: see for instance López & Alexiadou & Veenstra (2017), Alexiadou & Lohndal (2018), López (2020).

Still, most studies on HLs are exploring contact between two languages that are significantly distant, both typologically and structurally. Furthermore, a great deal of existing research considers HLs in comparison to either monolingual or other bilingual situations. This paper will not contribute to the debate on the profile of HSs and whether they should be compared to monolingual or bilingual speakers, but it will add an important piece to the puzzle of grammars in contact by looking at HLs spoken in contact between minimally different languages (“microcontact”). Moreover, we believe that detailed understanding of the phenomena and the output of contact situations is needed in order to draw sensible generalizations about the various factors at play in language change in contact. This paper provides a theoretically-informed description of a number of phenomena in heritage languages.

Our results show that, although the specific grammars that are in contact play a role in determining the output of change, and although our data are not completely homogeneous, some generalizations that have been observed for HL grammars are systematically disrespected when the contact languages are typologically very similar. Specifically, in this study we explore five important generalizations regarding HL syntax.

The first regards the tendency of HSs to avoid indeterminacy (Generalization 1, GEN1): it has been noted that if an item has several syntactic functions, only one of them will be selected in the HL (Polinsky & Scontras 2020). Our study on Differential Object Marking (Diez 1874; Meyer-Lübke 1899; Moravcsik 1978; Bossong 1985, 1991) shows that this generalization does not hold in microcontact.

Related to this, it is believed that HLs evolve in the direction of simplification (Generalization 2, GEN2; Polinsky & Scontras 2020). For instance, Tsimpli et al. (2004) and Sorace et al. (2009) observe that bilingual English-Italian and English-Greek children tend to use more overt subjects in their null-subject language; they attribute this to the fact that these bilinguals follow the model of English, which has only one option – overt – for the expression of subjects. Rather than choosing a system that requires mastery of intricate interface conditions for the distribution of subjects, they opt for the simpler system. Our data from both subject and object domains show that while this is largely true, microcontact does sometimes trigger cases of increased complexity, both morphological and syntactic, rather than simplification.

Moreover, the Interface Hypothesis (IH; Hulk & Müller 2000; Sorace 2005) maintains that interface phenomena (of the weaker language) are more vulnerable in language-contact situations, the rationale being that the more grammatical modules are involved in a phenomenon, the more vulnerable to change that phenomenon will be (see also Müller & Hulk 2001; Paradis & Navarro 2003; Serratrice & Sorace 2003; Serratrice & Sorace & Paoli 2004; and many others). In particular, the fact that some phenomena involving discourse and information structure tend to weaken in HLs is taken to mean that HSs do not easily master the interplay between syntax and discourse-related information (Generalization 3, GEN3). Data from both subject and object domains contradict this generalization, as far as microcontact is concerned.

Along the same lines, previous research has also shown that heritage speakers tend to avoid silence (Generalization 4, GEN4; Polinsky 2006; Laleko & Polinsky 2016, 2017), i.e. they typically avoid pro-drop or ellipsis through the insertion of overt elements where monolingual speakers would use silent ones. In this article we show that once again the situation in microcontact is different; null subjects are not only widely used, but also overextended with respect to monolingual use.

Finally, the indexicality domain has been shown to be the most stable domain in HLs (Generalization 5, GEN 5; Polinsky 2018a): our data from the nominal domain partially contradict this generalization. We do observe change in the indexical domain, especially in demonstratives, but this change is parallel to that witnessed in diachrony.

This paper is structured as follows. In Section 2, we introduce some necessary background information; in particular, we clarify the importance of considering contact between minimally different languages (Section 2.1), stress the specific challenges posed by Italo-Romance HLs, especially in relation to the baseline definition (Section 2.2), and provide an overview of our methodology (Section 2.3). The latter two issues have been addressed in more detail in Andriani et al. (in press). We then introduce in greater detail the generalizations that have been proposed to account for a wide variety of instances of syntactic change in HLs/bilingualism, along with our contradictory data, to form three case studies: “Avoid indeterminacy” and DOM (Section 3); the Interface Hypothesis, “Avoid silence”, and the tendency to simplification with subject and object data (Section 4); and the stability of the indexical domain with data from the D and T domains (Section 5). Section 6 concludes the article.

2. Background

3. Data collection

As stated at the outset, the remainder of the present study focuses on the novel generalizations drawn from our data and compares them to the generalizations in the literature that drawn on the basis of one-to-one investigations of language pairs. In this section we present the phenomena that we investigated (Section 3.1) and describe the participants’ profiles and the tasks involved in our study (Section 3.2). For a detailed overview of the data collection, and for remarks on the design of the questionnaire and the issues that arose from fieldwork, the reader is referred to Andriani et al. (in press).

3.2. Tasks, materials, and procedure

Our study is based on fieldwork data collected by our research team in Argentina, Brazil, and Canada. We considered five Italo-Romance varieties (Venetan, Trentino, Abruzzese, Calabrian, Sicilian) and one Rhaeto-Romance variety (Friulian)⁹ in contact with Argentinian Spanish, Brazilian Portuguese, and Quebec French.¹⁰ Italo-Romance data were also collected for control purposes in the area of New York City (NYC), thus in contact with English. These Italo-Romance varieties were chosen on the basis of the phenomena that we targeted and because their speakers have very similar sociolinguistic profiles: G1 speakers mostly left Italy after World War II to relocate in one of the American countries. Crucially, they were for the most part monolingual speakers of the Italo-Romance varieties, as Italian only started to be taught systematically at school around the time they left Italy.¹¹ This means, in turn, that the Italo-Romance varieties spoken in Italy today usually differ from those that were spoken when G1 speakers left (but see Section 1.2 above).

The data discussed here were collected during a preliminary set of fieldwork sessions that took place in spring 2019. A second, longer round of fieldwork was planned, but could not be carried out because of the Covid-19 outbreak. The first fieldwork session was intended to be more descriptive than analytical: given that most of these varieties had not been described at all, we first needed to check what the relevant structures looked like, before attempting any analysis. A quantitative overview of our fieldwork data is presented in Table 2.

Table 2

Overview of the speakers interviewed in our study by spoken Italo-Romance variety, country of immigration, and generation. An indication of the size (in terms of duration) of our spontaneous speech corpus is also provided.¹²

	Argentina	Brazil	Quebec	NY	(Belgium)	Total nr of speakers	Total minutes
Abruzzese	9 speakers •7 G1 •2 HS	–	2 •2 G1	3 •1 G1 •2 HS	1 •1 G1	15 •11 G1 •4 HS	>150’ •110’ G1 •40’ HS
Calabrian	9 •8 G1 •1 HS	3 •2 G1 •1 HS	5 •5 G1	–	–	17 •15 G1 •2 HS	>170’ •150’ G1 •20’ HS
Friulian	8 •4 G1 •4 HS	7   •7 HS	7 •7 G1	6 •4 G1 •2 HS	–	28 •15 G1 •13 HS	>280’ •150’ G1 •130’ HS
Sicilian	13 •10 G1 •3 HS	2 •2 G1	5 •4 G1 •1 HS	10 •8 G1 •2 HS	5 •4 G1 •1 HS	35 •28 G1 •7 HS	>350’ •280’ G1 •70’ HS
Trentino	3 •3 G1	7   •7 HS	–	–	–	10 •3 G1 •7 HS	>100’ •30’ G1 •70’ HS
Venetan	16 •12 G1 •4 HS	28 •2 G1 •26 HS	8 •7 G1 •1 HS	–	–	52 •21 G1 •31 HS	>520’ •210’ G1 •310’ HS
Other	15 •14 G1 •1 HS	3 •1 G1 •2 HS	9 •9 G1	39 •19 G1 •20 HS	2 •1 G1 •1 HS	68 •44 G1 •24 HS	>680’ •440’ G1 •240’ HS
total	73 •58 G1 •15 HS	50 •7 G1 •43 HS	36 •34 G1 •2 HS	58 •32 G1 •26 HS	8 •6 G1 •2 HS	225 •137 G1 •88 HS	–
total minutes	>730’ •580’ G1 •150’ HS	>500’ •70’ G1 •430’ HS	>360’ •340’ G1 •20’ HS	>580’ •320’ G1 •260’ HS	>80’ •60’ G1 •20’ HS	–	>2250’ •1370’ G1 •880’ HS

Admittedly, the sample is rather varied, as we explained before. Nevertheless, some robust generalizations emerged and are worth reporting.

The methodology for this first round of fieldwork was comprised of three grammatical tasks: a forced-choice task, a picture-sentence matching task, and a semi-guided production task. We additionally used a spontaneous production task in which our informants were asked to tell a short story about their childhood: in this way, a large corpus of spontaneous speech was collected (approx. hours: 37h30’, see details in Table 2). In order to check the HL proficiency of the speakers, we asked for a self-evaluation, via a sociolinguistic questionnaire. We also prepared a short picture-naming task in both the HL and the dominant language, inspired by the HALA test (O’Grady et al. 2009).

In the forced-choice task, we asked our informants to listen to audio stimuli (recorded by native speakers of the same variety as is spoken in Italy today) containing minimal pairs. For each pair, our informants had to choose the “right”, i.e. most natural, sentence. For DOM, the pair was formed by two sentences with and without a DOM-marked object, as shown in (4):

1. (4)

1. Calabrian

1.  
1. a.

1. Tə
2. refl
1. nsunnastə
2. dreamt.2sg
1. chə
2. that
1. baciastə
2. kissed.2sg
1. a
2. dom
1. idda.
2. her
1. ‘You dreamt that you kissed her’

1.  
1. b.

1. Tə
2. refl
1. nsunnastə
2. dreamt.2sg
1. chə
2. that
1. baciastə
2. kissed.2sg
1. idda.
2. her
1. ‘You dreamt that you kissed her.’

With respect to DOM, we examined data elicited from 2 Abruzzese, 4 Friulian, 4 Sicilian, and 3 Venetan HSs in Argentina; 3 Friulian and 8 Venetan HSs in Brazil; and 1 Sicilian and 1 Venetan HS in Canada. Speakers of northern varieties completed a questionnaire that included 9 sentences testing DOM plus 14 fillers (some of which tested subject clitics; see below), for a total of 23 sentences, whereas speakers of southern varieties had 13 DOM sentences plus 11 fillers, for a total of 24 sentences. We chose to give an unequal number of questions to the two groups as we were not expecting production of DOM on a wide range of arguments by speakers of northern varieties, since most of these do not exhibit DOM in their homeland counterparts. The stimuli were presented in random order.

The forced-choice task also contained items targeting subject clitics (see Frasson & D’Alessandro & van Osch 2021), for which the participants were asked to choose between a minimal pair with and without the subject clitic. There were 15 speakers of Friulian who participated in this task: 8 in Argentina (3 G1; 5 HSs) and 7 in Brazil (all HSs). For the results concerning subject clitics, we also analyzed the spontaneous production data from 15 speakers: 8 in Argentina (3 G1; 5 HSs) and 7 in Brazil (all HSs). In total, there were 580 sentences, of which 375 contained a subject clitic and 205 did not.

The second and third tasks were designed specifically for demonstratives: the purpose of this study was to assess whether or not ternary demonstrative paradigms, i.e. demonstrative systems with three contrastive forms, were retained in HLs (see Section 3.1.3 for details). The only varieties in our sample that have this system are some varieties of Abruzzese, Sicilian, and Calabrian, so only 38 speakers participated in this part of the task, distributed as follows: in Argentina, 2 Abruzzese, 1 Calabrian, 3 Sicilian HSs and 5 Abruzzese, 5 Calabrian, 6 Sicilian G1 speakers; in Brazil, 2 Sicilian G1 speakers; in Quebec and Belgium, 2 Sicilian HSs and 3 Abruzzese, 2 Calabrian, 7 Sicilian G1 speakers.

In order to test the organization of demonstrative paradigms, we performed a picture-matching task, in which our informants were shown pictures representing the three different deictic domains (related to the speaker, related to the hearer, and related to neither) and were asked to choose, from a set of audio stimuli, the one that best described the given picture. For instance, given the representation of the speaker-oriented domain (Figure 1, where the dog is close to the speaker), the target answer would have been of the ‘this’ type.

Figure 1

Speaker-oriented deictic domain.

Each domain was tested in three different syntactic environments: pronominal (‘this/that is… dog’), adnominal (‘this/that dog is…’), and in a demonstrative-reinforcer construction (‘this here/that there…’). Finally, we collected semi-guided production data by asking our informants to refer to or locate target objects in the actual interview setting. In this last task, we elicited each of the three deictic domains twice: once by means of demonstrative forms (‘which one is…?’, to yield ‘it’s this’ vs ‘it’s that’ type answers), and once by means of a locative adverb (‘where is…?’, to prompt ‘it’s here’ vs ‘it’s there’ type answers). Thus, each deictic domain was elicited 5 times (i.e. in 5 different conditions) for each speaker. The elicited responses were transcribed and subsequently the demonstrative forms were coded according to their morphology as formally proximal, medial, or distal, to avoid making explicit connections with the semantics of those same forms (see Section 5 for details).

In the following sections, we report the results of our investigation and show how they conflict with the generalizations that have been established for HL syntax.

4. Generalizations 1 and 2: “Avoid indeterminacy” and tendency to simplification

The first generalization that we review here is related to indeterminacy. Several studies have concluded that HSs tend to avoid indeterminacy, that is, if a lexical item has several syntactic functions, only one of them will be selected in the HL (Montrul & Bowles 2009; Polinsky 2011). An example of indeterminacy is provided by the morphological DOM-marker a, employed in several Romance varieties (see Section 2.3.1). In the varieties under investigation here, the DOM-marker a is syncretic with that of datives, locatives, object experiencers and, potentially, topics.

According to GEN1, just one of the functions of a should be selected in heritage languages in order to avoid indeterminacy or ambiguity. Most of the loss or reduction of DOM in contact studies or bilingualism can be attributed to the multiple functions of this element (Polinsky 2006; Pascual y Cabo 2013; Montrul & Bhatt & Girju 2015). This is related to GEN2: heritage languages show a tendency to simplification, which means that a given linguistic element either loses one of more functions, or the element itself is lost or weakened.

In addition, DOM is also an interface phenomenon that requires the integration of syntactic and extra-syntactic knowledge (topicality, animacy, definiteness). This should make it more vulnerable to change (Montrul 2011). We will return to this in Section 4 in relation to GEN3.

Regarding the vulnerability of DOM, several studies (Silva-Corvalán 1994; Luján & Parodi 1996; Montrul 2004; Montrul & Bowles 2009; Montrul & Sánchez-Walker 2013; Montrul & Bhatt & Girju 2015) have shown that DOM weakens in Heritage Spanish spoken in the US. This conclusion is also supported by evidence from outside the Romance domain: Polinsky (2006, 2018a: 185–186) observes that HSs of Russian in the US tend to lose DOM, despite their perfect mastery of dative and accusative marking. Our data show the same tendency in heritage Southern Italo-Romance in contact with US English in NYC:

While all these varieties present DOM in their homeland counterpart, the data in (5)-(7) show that the DOM-marker is dropped almost everywhere in heritage Italo-Romance varieties spoken in NYC. This is in accordance with what has been described in other studies on contact. Note, however, that in no case does the weakening of differential marking of DOs lead to its complete loss: it is in fact retained with the most prototypically DOM-marked referents, i.e. personal pronouns (5a), (6a), (7a), but it is absent with other referents which would bear the a-marking in the homeland and baseline varieties (see the hierarchy in (i), Section 3.1.1). In particular, the a-marking is lost with kinship terms, as in (5b), (6b), (7b) and other highly referential/specific expressions, i.e. with demonstratives, as in (5c), definite referents, (6c), and universally quantified referents, e.g. ‘all the family’ (5d) and the pronoun ‘everyone’ (5e). Our control group for contact between Italo-Romance and English in NYC behaves exactly as expected.

Microcontact, however, presents a completely different picture. The data collected in Argentina challenge GEN1: there, not only is DOM preserved, or even extended, in Abruzzese and Sicilian, but it also emerges in non-DOM varieties such as Friulian and Venetan. As an example of expansion, consider (8) in Heritage Abruzzese:

Example (8) illustrates a case of extension of DOM to items that would not require it in homeland Abruzzese, where animals – and, in some varieties, 3^rd-person referents – are not introduced by the preposition. Example (9) illustrates the emergence of differential marking in Heritage Friulian, a variety traditionally considered as lacking DOM in its homeland counterpart:

While varieties lacking differential marking of DOs, such as Venetan and Friulian, tend to accept DOM to a lesser extent than Abruzzese and Sicilian, the acceptance rate for all heritage varieties is higher than in their homeland counterpart (except for Sicilian varieties, cf. Manzini & Savoia 2005; Guardiano 2010). Despite these general tendencies, some differences can be found with respect to the degree of acceptability of DOM depending on the contact language: differential marking of DOs is considerably higher in heritage varieties in Argentina than in Brazil and Canada,¹³ as shown in Figure 2:

Figure 2

Percentage of DOM and non-DOM marked objects in a forced choice task with HSs of Abruzzese, Friulian, Sicilian, and Venetan in Argentina, Brazil, and Canada.

The elicited data show similar patterns to Abruzzese and Sicilian spontaneous speech.¹⁴ We also find many instances of DOM in the spontaneous speech of Heritage Friulian:

These results are in keeping with earlier findings on Catalan DOM in (micro)contact with Spanish: while Standard Catalan only has obligatory DOM with pronouns and dislocated DPs, non-standard varieties of Catalan preserve DOM and actually expand its context of occurrence, possibly because of contact with Spanish:

Interestingly, our data from Venetan show an asymmetry between the results of the forced-choice task and spontaneous speech. In the forced choice task, the DOM option was chosen over the non-DOM option in 48% of cases by HSs (38% if we add G1 speakers), despite the fact that homeland Venetan is generally regarded as non-DOM – with some exceptions found in Triestino (Rohlfs 1969; 1971) and Paduan (Fabris 1928: 14). In spontaneous production, on the other hand, they never produced DOM. Given this discrepancy, we leave the Venetan data aside for further investigation.

The facts reported here constitute systematic counterexamples to GEN1 and GEN2:¹⁵ indeterminacy is not resolved in HLs in microcontact, but is preserved and possibly even strengthened. The a-marker is consistently selected for DOM and other uses (e.g. datives and locatives). In the case of Friulian, HSs extend the use of a to differential marking of DOs, which is not found in the homeland grammar. We can therefore argue that in this case the heritage variety has become more complex, rather than simpler, than the homeland variety.

5. Generalizations 3 and 4: the Interface Hypothesis and null elements

The third generalization that we address in this paper is the Interface Hypothesis (IH): change targets structures that involve several grammatical modules (Hulk & Müller 2000; Sorace 2005, 2011; Sorace & Serratrice 2009; Sorace et al. 2009; a.o.). The core of the hypothesis is that strictly grammatical phenomena are less vulnerable, because they only require mastery of one module; instead, phenomena at the interfaces between different modules, such as syntax, discourse, and information structure, are more vulnerable, as they require the integration of more modules and hence have higher computational and processing loads. The IH was originally proposed to account for adult L2 learners and was later widely used to explain the linguistic behavior of bilinguals; it has also been applied to the study of HLs (see e.g. Benmamoun & Montrul & Polinsky 2013 and references therein).

In this discussion, we specifically target the syntax-discourse interface, which we explore with reference to two different phenomena: DOM and null subjects (NS). While NS are situated at the syntax-discourse interface, DOM typically involves the internal interface between syntax and semantics. In some cases, however, it also touches upon the syntax-pragmatics interface. For both DOM and NS, then, syntactic computation must be integrated with information-structure requirements: this integration is computationally heavy, so both phenomena are predicted to be vulnerable to change in contact situations.

In the previous section we showed that differential marking of DOs is preserved, or even strengthened, in heritage Italo-Romance varieties in (micro)contact with Argentinian Spanish. The contexts in which this extension takes place usually involve a fronted topic. It has been argued, in fact, that topicality favored the emergence of DOM in a number of early Romance varieties. Pensado (1995) shows the relevance of topicality in the rise of DOM in old Spanish; Iemmolo (2009, 2010) observes the same behavior in Old Sicilian, while Ledgeway (2009) shows that old Neapolitan had a contrast between unmarked in-situ DOs and marked dislocated (i.e. topicalized) ones. Our data also show that DOM is accepted significantly more often with fronted topicalized objects than with in-situ objects, as illustrated in Figure 3:

Figure 3

Percentages of DOM and non-DOM with both topicalized and non-topicalized constructions in a forced choice task with HSs of Abruzzese, Friulian, Sicilian, and Venetan (data grouped across the three different host countries).

This difference between DOM with topicalized and non-topicalized objects was significant for Abruzzese speakers (DOM extension; 6 G1, 2 HSs) and Friulian speakers (4 G1, 4 HSs), although for the latter it emerged that the effect was only significant for HSs (z = –3.14, p = .006), and not for the G1 migrants:

While homeland Abruzzese, Friulian, Sicilian, and Venetan do have topicalization strategies, these do not trigger differential marking of DOs. DOM is widespread in Abruzzese and Sicilian, and is triggered by the semantic features of the objects, such as specificity and definiteness. In these varieties, the classes of objects that are available for a-marking will have DOM independently of their syntactic position (with the exception of some Sicilian varieties, where differential marking is favored in topic position with some referents lower in the definiteness/animacy hierarchy; see Guardiano 2010). In Heritage Abruzzese, Friulian, Sicilian, and Venetan DOM is instead introduced or strengthened in topicalization contexts, to different extents.

This shows that HSs introduce discourse-related constraints on DOM, like topicality, that are not crucial in the realization of DOM in the baseline; in doing so, they defy the IH by showing good mastery of a discourse-related operation, i.e. topicalization, involving the syntax-pragmatics interface. Indeed, these facts seem to indicate that syntactic change penetrates into the system from the periphery of the clause.

Turning to null subjects, the IH predicts that the production of NS will be affected by the computationally taxing integration of syntax and pragmatics.¹⁶ Research on both L2 and HLs has shown that this is the case for NS. When a pro-drop language enters into contact with a non-pro-drop language there are two possible logical outcomes. The first outcome is that the NS is partially lost, and that speakers of originally pro-drop languages actually start inserting overt subjects in contexts in which they are not used by monolingual speakers. This has been attested in many studies, such as Paradis & Navarro (2003) and Serratrice et al. (2004) for English-Italian; Sorace et al. (2009) for English-Italian and Spanish-Italian; Müller et al. (2006) for German-Italian.

The second logical possibility is that non-pro-drop languages can become pro-drop, but this is barely attested. The emergence of pro-drop would imply an increase in the complexity of a system. In non-pro-drop languages all subjects are overt, regardless of discourse and context factors, so they display a simpler system for subject insertion than pro-drop languages, in which the insertion of an overt subject is dependent on specific discourse-related factors (Tsimpli et al. 2004, Sorace et al. 2009). The preference for the simpler system is usually chosen by L2 speakers as well as heritage speakers (Sorace et al. 2009). Other more gradable options are also found.

Although the main tendency is towards the use of overt subjects, null subjecthood can also sometimes remain unaffected, or even be extended. Data pointing in this direction have been found by Pinto (2013) for Dutch speakers of L2 Italian; Montrul (2004) for HSs of Spanish in the US; Montrul & Rodriguez Louro (2006) and Rothman (2009) for American-English L2 speakers of Spanish. The tendency to maintain the pro-drop status of the language is only marginally attested in contact situations, and therefore considered a deviation from the norm. However, studies on microcontact, such as contact between Spanish and Portuguese, have reported similar results (see in particular De Prada Pérez 2009 on Catalan-Spanish; Carvalho & Child 2011 and De Souza et al. 2018 on Spanish-Portuguese).

For our study, we looked at subject clitics in Heritage Friulian, both in contact with English in the US and in microcontact situations in Argentina and Brazil. As mentioned above, subject clitics are always obligatory, while tonic pronouns can be dropped in certain discourse contexts, similar to other null subject languages.

In our control group of Heritage Friulian in the US, subject clitics are indeed always obligatory in the context of topic continuity, on a par with homeland Friulian (see (14a) below). In particular, we note that subject clitics are realized whenever a finite verb appears, regardless of discourse conditions, as expected for markers of φ-agreement. This is illustrated in (13):

However, Frasson & D’Alessandro & van Osch (2021) show that in heritage varieties of Friulian spoken in microcontact situations in Argentina and Brazil, subject clitics display occasional pronominal behavior, in that they can be dropped in the second conjunct of coordinated structures (14b), while this is impossible in the homeland variety (14a):

Frasson & D’Alessandro & van Osch (2021) observe a two-step development: agreement clitics are not mere φ-bundles like in the homeland variety, but are full pronouns. These pronouns are then dropped, creating a pro-drop context that is not present in the homeland grammar. Moreover, the spontaneous production data show an effect of topicality for subject drop in Heritage Friulian: HSs are more likely to produce a clitic when there is a shift in topic with respect to the previous sentence (15), compared to cases of topic continuity (16):

The effect can be seen in both Brazilian and Argentinian heritage speakers, but is only significant in Argentina, as illustrated in Figure 4.

Figure 4

Percentages of subject clitic use in Heritage Friulian (spontaneous production) in Argentina and Brazil.

This indicates that specific interface conditions trigger subject drop. Contrary to what is expected under the IH, HSs introduce new discourse-related constraints on pro-drop that are unavailable in the baseline, namely the use of topicality. This suggests that HSs in microcontact situations do not face specific difficulties with the computation of discourse operations; on the contrary, they exploit these discourse strategies to create new structural configurations, like pro-drop, which are unavailable for subject clitics in the homeland variety. In addition, the different outcomes in the two contact situations suggest that the effects of language contact are not solely due to cognitive issues and can therefore emerge as a consequence of specific language pairings.

The data on subject clitics that we have just presented also allow us to reassess the fourth generalization, related to silent elements: HSs have been shown to be uncomfortable with silent elements (Polinsky 2006; Laleko & Polinsky 2016) and hence to tend to avoid them, possibly because of processing issues.

Friulian data from Argentina and Brazil plainly contradict this generalization, given that some of the HSs we interviewed introduced new silent elements into their systems. Heritage Friulian speakers in Argentina and Brazil in fact allow for a pronominal use of subject clitics (obligatory agreement markers) that can therefore be omitted, as predicted for pronominal elements in null-subject languages: that is, in our data we see that an element that used to be obligatory in the homeland variety becomes optional in the HL. Thus, HSs in microcontact situations are comfortable with silence, given the appropriate discourse conditions.

Finally, the data from both DOM and subject clitics in microcontact contradict GEN2, which predicts that change in contact should entail simplification. For DOM, we see that Italo-Romance varieties that do not have DOM in the baseline can integrate DOM marker into their grammars, when in contact with another DOM language. For subject clitics, we see that some varieties reanalyze these clitics as pronouns that can be dropped under the right discourse conditions. Thus, in both cases we see that the systems have started to include more variation rather than less: where there was a one-to-one mapping in the baseline variety, we now have a one-to-many mapping in the heritage variety. Moreover, for both of these properties, discourse constraints are added to a domain that was purely syntactic in the baseline. We can therefore conclude that, at least for these phenomena, heritage speakers are not simplifying their languages; if anything, they are making them more complex.

6. Generalization 5: Stability of the indexical domain

The last generalization we consider concerns the indexical domain, which is generally believed to be unaffected by contact in HLs (GEN5, Polinsky 2018a), a conclusion supported by wider evidence from contact linguistics (Nichols 1992; Heine & Kuteva 2005; Friedman 2006; Matras 2009). The only type of change that we can observe in indexical elements is diachronic in nature, i.e. endogenous. This is confirmed by our data in microcontact, but surprisingly only partially by our findings in contact.

7. Conclusions

In this paper, we have shown that microsyntactic variation offers an important additional set of data for understanding what is involved in change; it allows holistic typological considerations to be factored out in order to focus solely on structural factors. The outputs of CIC related to the different language pairs involved vary slightly, but they show tendencies that overall contradict what has been reported in the existing literature, which is mainly based on contact among typologically different languages. Specifically, we have shown that GEN1-GEN4 (and partially GEN5) are contradicted by microcontact data. We maintain that these generalizations do not hold across the board because they have been established on the basis of structurally distant languages alone. This paper offers a methodological contribution to the study of language contact, in that it shows that introducing a microcontact perspective is not only desirable, but necessary. Furthermore, checking the same phenomenon in multiple contact situations offers a clearer picture of the factors involved and the incipient direction of language change.

Abbreviations

aux = auxiliary, cic = change in contact cl = clitic, dem = demonstrative, dom = Differential Object Marking, hl = heritage language, hs = heritage speaker, inf = infinitive, ns = null subject, pl = plural, scl = subject clitic, sg = singular.

Funding information

This research received funding by the European Research Council under the Horizon 2020 Research and Innovation Programme (grant agreement ERC CoG 681959_MicroContact).

Competing interests

The authors have no competing interests to declare.