The prehispanic city of Tzintzuntzan—built on the slopes of the Yarahuato and Tariaqueri hills on the shores of Lake Pátzcuaro with wide terraces and large platforms—was the capital of the Tarascan Empire. This empire comprised farming and fishing communities and was characterized by a multiethnic population with a highly hierarchical social structure (Pollard Reference Pollard1993, Reference Pollard, Sanders, Mastache and Cobean2003). It dominated a vast territory—more than 75,000 km² of western Mexico during the fifteenth and sixteenth centuries—and fiercely rivaled the Mexica. The Uacúsecha lords—Eagle lords—governed through a hereditary dynasty.

Tzintzuntzan functioned not only as the Tarascan capital but also as a ritual center and regional market. As such, its residents engaged in basic, ritual, and elite craft production, and it housed the empire’s most important ritual spaces and the royal residence of the ruler, the calzonci (Pollard Reference Pollard, Sanders, Mastache and Cobean2003, Reference Pollard, Williams and Esparza2009, Reference Pollard, Roskamp and Albiez-Wieck2016; Punzo-Díaz and Navarro Reference Williams2022). After the Spanish conquest of Michoacán—considered central to the process of colonization in Mexico—the Tarascan nobility coexisted with the Spanish for a good part of the sixteenth century, as Tzintzuntzan gradually lost its importance as a colonial city to the neighboring Pátzcuaro. Tzintzuntzan was then abandoned, leaving behind multiple archaeological remains on the hillsides that have yet to be fully explored (Pollard Reference Pollard1977, Reference Pollard1987, Reference Pollard, Sanders, Mastache and Cobean2003; Punzo et al. Reference Punzo-Díaz and Navarro2022). Thus, this site is a unique place for the study of the transition from prehispanic societies to those of the early colonial period.

The residents of Tzintzuntzan exploited Lake Pátzcuaro’s resources through fishing and gathering plants (Pollard Reference Pollard1987, Reference Pollard, Sanders, Mastache and Cobean2003). The fishing communities in the city and the surrounding villages of the lake and its islands were very important for the population’s livelihood and society, as documented by historical texts. La relación de las cerimonias y rictos y población y gobernación de los indios de la provincia de Mechuacán (known as La Relación de Michoacán) describes many of the elements of the daily life of the Uacúsecha lords and people who inhabited the surroundings of Lake Pátzcuaro at the time of contact with the Spaniards (Alcalá Reference Alcalá2008 [1540]; Williams Reference Williams2022).

Diseases of the ear are a relevant health concern for members of fishing communities. Otitis and mastoiditis often resulted in deafness and disability in the pre-antibiotic era (Flohr and Schultz Reference Flohr and Schultz2009a; Garrido Campos et al. Reference Campos, Astrid, Anselm Hindelang, De Carvalho, Urzua Finke Siqueira, Herrera and Radon2018; Goycoolea and Castro Reference Goycoolea, Castro, Goycoolea, da Costa, de Souza and Paparella2023). These two pathologies co-occur because mastoiditis is a sequela of otitis media: recurrent infections of the middle ear and, by extension, the mastoid, lead to a chronic inflammatory process that produces sclerosis and lytic destruction of the bony structures of the temporal bone, particularly if there is no antibiotic treatment.

Otitis media is the term used when the middle ear suffers an inflammation of the mucosa or ear epithelium that, in severe cases, extends to the temporal bone. Frequent exposure to water—especially contaminated water like that of a lake—increases the possibility of illness because it can enter through perforated or softened tympanic membrane and produce acute inflammation (Flohr and Schultz Reference Flohr and Schultz2009b; Goycoolea and Castro Reference Goycoolea, Castro, Goycoolea, da Costa, de Souza and Paparella2023; Gremba Reference Gremba2020). Swimmers who depend on fishing and hunting to obtain food are at risk of recurrent infections throughout their life due to prolonged submersions. Those infections can impair the transmission of sound to the inner ear, resulting in hearing loss or deafness. Water immersion has been shown to cause hearing loss in longitudinal follow-up studies of divers (Flohr and Schultz Reference Flohr and Schultz2009b; Goycoolea and Castro Reference Goycoolea, Castro, Goycoolea, da Costa, de Souza and Paparella2023; Wingelaar et al. Reference Wingelaar, Endert, Hoencamp, van Ooij and van Hulst2019).

Hearing loss is classified as sensorineural, conductive, or mixed type. Conductive hearing loss involves the tympanic membrane and the middle ear, interfering with sound transmission and conversion to mechanical vibrations. Sensorineural hearing loss affects the mechanical conversion of sound to neuroelectric signals in the middle ear or the auditory nerve; it is most often due to damage to the hair cells of the inner ear (Davis and Hoffman Reference Davis and Hoffman2019).

There is no universally accepted definition of hearing loss; diagnosis is made by self-report and definitively by audiometry (Michels et al. Reference Michels, Duffy and Rogers2019). However, data suggest that middle ear and mastoid damage leading to varying degrees of hearing loss can be identified at the imaging level.

Lesions in the structures in the middle and inner ear, as well as mastoid cells, can be of different types: erosions, expansions, and lytic and blastic lesions. These are compatible with postmortem and imaging diagnoses of untreated chronic otitis and mastoiditis (Garrido Campos et al. Reference Campos, Astrid, Anselm Hindelang, De Carvalho, Urzua Finke Siqueira, Herrera and Radon2018; Gremba Reference Gremba2020). Furthermore, there is evidence that these pathologies of the temporal bones likely correspond to presumptive diagnoses associated with hearing loss, as discussed earlier. Advances in the application of imaging studies have made it possible to document these changes in ancient bone remains (Zhang et al. Reference Zhang, Zhao, Niu, Wang and Zeng2020).

Most of the paleopathology literature on diseases of the ear focuses on inflammation of the mastoid. Mastoiditis has been primarily identified using conventional radiography to an acceptable degree of success, especially considering the temporal bone’s complex structure (Castro et al. Reference Castro, Goycoolea and Silva-Pinto2017; Zhang et al. Reference Zhang, Zhao, Niu, Wang and Zeng2020). However, growing evidence in recent years suggests that computed tomography (CT) is a superior imaging method to identify pathologies in the temporal bone (Purchase et al. Reference Purchase, Bazaliiskiib and Lieversec2019). Even so, there are few publications using this approach to analyze ancient remains.

Otitis and mastoiditis have been documented in several archaeological studies in Asia and Europe (Flohr and Schultz Reference Flohr and Schultz2009a, Reference Flohr and Schultz2009b; Goycoolea and Castro Reference Goycoolea, Castro, Goycoolea, da Costa, de Souza and Paparella2023). In South America, a previous study in a prehistoric coastal population in Chile found a high prevalence of otitis; however, it did not report the degree of progression of this disease or its social implications (Garrido Campos et al. Reference Campos, Astrid, Anselm Hindelang, De Carvalho, Urzua Finke Siqueira, Herrera and Radon2018).

A bioarchaeology of care model can be useful for exploring those social implications. This approach involves analyzing human remains, with lifestyle parameters observed in context. In this way, it identifies and interprets the experience of illness and disability and any association with health care (Tilley Reference Tilley, Tilley and Schrenk2017; Tilley and Shrenk Reference Tilley, Alecia, Tilley and Schrenk2017). Concepts key to bioarchaeology of care model are care, disability, health, illness, and death.

Care can be defined as the act of providing what is needed to maintain the health, well-being, and protection of an individual, entity, or object: it is shaped by the cultural, economic, social, and physical environments in which individuals develop or operate in (Tilley Reference Tilley, Tilley and Schrenk2017; Tilley and Schrenk Reference Tilley, Alecia, Tilley and Schrenk2017). Analyzing the characteristics of care—specifically, how it is provided and received—across different cultures and societies allows for a more nuanced understanding of their motivations, commitment to care, and their values, traditions, experiences, knowledge, beliefs, resources, and social organization. The narrative of care can be reconstructed in three phases: from the onset of the disease or health condition, including the functional and social limitations that can arise from that condition (start); followed by the care provided and received (event); and how this care enables the functioning of a person until death (end). Applying this approach to archaeology, we can construct narratives of care based on knowledge gained about an individual’s way of life in the past (Tilley Reference Tilley, Tilley and Schrenk2017; Tilley and Schrenk Reference Tilley, Alecia, Tilley and Schrenk2017).

Another fundamental principle of the bioarchaeology of care is the bioarchaeology of disability, which proposes an approach to disability in ancient populations. It combines bioarchaeological and paleopathological analyses and clinical interpretations in an archaeological context. Its objectives are to identify individuals in a community with some physical limitations and to explain the functionality and social impact of these limitations based on inferences from social attitudes toward disability (Bohling et al. Reference Bohling, Croucher and Buckberry2022).

The aims of our study are to (1) analyze pathological lesions in the temporal bones of skeletal remains from the Tarascan culture living near Lake Pátzcuaro, using a multidisciplinary approach combining bioarchaeology, medicine, and physical anthropology, and (2) interpret the impact on daily life of having lesions compatible with chronic otitis and mastoiditis (detected by multidetector computed tomography [MDCT] imaging), whose consequences can include probable hearing loss and disability, from the perspective of the bioarchaeology of care and bioarchaeology of disability.

Materials and Methods

Setting

The bone samples (temporal bones) analyzed were from three archaeological contexts in the city of Tzintzuntzan: the La Zarzamora sector excavated in 1969, a sector of the main platform excavated in 1992, and another sector of the main platform excavated in 2011, which had been identified as the ossuary of the city. All three locations are dated to the fifteenth century, which correspond to the time before contact (Figure 1). It is important to mention that these bone deposits, especially those in the ossuary, are from a large number of individuals of both sexes and all age groups, mostly young adults and adults. We selected samples that presented abnormal lesions at a macroscopic level. Figure 2 describes the phases of the multimethod approach informed by the different perspectives—physical anthropology, medicine, paleoimaging, and ethnohistorical sources—used to interpret the bioarchaeology of care.

Figure 1.

Map of study area, where temporal bone samples were analyzed from two nearby sites in Tzintzuntzan, Michoacán, Mexico: (1) La Zarzamora (green), in which 20 skulls were found in a semicircle, and (2) La Gran Plataforma (red), where an ossuary was excavated. (Color online)

Figure 2.

Methodology integrating different approaches to interpret the bioarchaeology of care: physical anthropology, medicine, paleoimaging, and ethnohistorical sources.

Phase 1: Questionnaire Construction and Validation

An evaluation of each temporal bone’s taphonomic and pathological characteristics was carried out by six evaluators from different disciplines: two physical anthropologists, two clinical radiologists, a neurosurgeon, and a dual-trained archaeologist and medical doctor. A questionnaire was designed to evaluate the temporal bones, based on a review of the medical and bioarchaeological literature and informed by the experience of the participating researchers. Using a consensus exercise, the researchers selected the following domains: anatomical location, taphonomic changes, and description of pathologies (Supplementary Figure 1). Determining age-at-death of the sampled individuals was difficult because of the fragmentation of the analyzed temporal bones. However, based on their professional experience, the participating physical anthropologists considered that most samples came from adult individuals.

A questionnaire of 25 variables was constructed to assess three domains: (1) description and location of the area to be evaluated in the temporal bone (faces, portions, surfaces, and laterality); (2) taphonomic characteristics, such as the degree of preservation and thermal, chemical, and flora or fauna alterations; and (3) anomalies or pathological data of the lesions, such as shape, borders, erosions, texture, number, pattern, temporality, and type (see Supplementary Text 1).

A pilot test was then carried out in which each researcher applied the questionnaire separately and blinded on a sample of 10 temporal bones from archaeological assemblages collected from two archaeological sites in the same region of Michoacán. The first assemblage was recovered from the Urichu site (Pollard and Cahue Reference Pollard and Cahue1999), which is located a few kilometers southwest of Lake Pátzcuaro. The second assemblage is from an earlier site, the Loma de Santa María site (Cárdenas Reference Cárdenas, Williams and Weigand1999), located in the Cuitzeo basin. The objective of the pilot test was to standardize the evaluations and ensure that the questionnaire was suitable for detecting lesions compatible with otitis, mastoiditis, or both. Researchers conducted their evaluations independently, and the results were summarized in a spreadsheet. One of the researchers (Ingris Peláez-Ballestas) analyzed the evaluations to identify differences and concurrence. Any disagreements in identifying or diagnosing lesions were resolved using consensus techniques, so that consensus was higher than 80% (data not shown).

After completing the pilot study and standardizing the assessments, two physical anthropologists and a neurosurgeon conducted the evaluations using the validated questionnaire. The analysis was complemented by an MDCT protocol used for current bone remains, which was supervised by two radiologists.

Phase 2: Physical and 2D Photogrammetric Evaluation

Photogrammetric and physical analyses were then performed. Structure from Motion (SfM) is a preferred method for documenting funerary contexts in the archaeological record, because it is easy to use and does not require specialized equipment. Photogrammetry uses a series of 2D photographs of objects or landscapes that are processed through computer programs, the most common being Agisoft Metashape. These programs use computational algorithms that identify common points in the photos, calculating the position of these points relationally in a three-dimensional space, forming a point cloud. The quality of the models generated is variable and depends on the quality of the point cloud (coverage and density), the quality of the light and the camera used, and the number and location of each photograph. Thus, capturing more photographs increases the complexity and detail of the surface, resulting in better models (Gastelum-Strozzi et al. Reference Wrobel and Tiesler2019; Wrobel Reference Wrobel and Tiesler2022). Geometric morphometry is a 2D digital method that complements traditional analyses and allows comparisons with traditional osteometry. Another method is the MicroScribe digitizer, in which an articulated arm identifies points in an immobilized bone to record and reconstruct its entire surface (Wrobel Reference Wrobel and Tiesler2022).

Photogrammetric analysis was performed to improve the evaluation of the lesions because this method allows a better definition of the physical characteristics measured in the questionnaire (Supplementary Figure 2).

Phase 3.1: Imaging Evaluation

MDCT (Siemens Sensation 128) was chosen for this study because it is the most suitable method for evaluating the middle ear and mastoid (Khan et al. Reference Khan, Deshmukh and Gaurkar2022). Multiplanar reconstructions of the raw data were made in axial and coronal planes, with an image thickness of 0.5–0.6 mm and a distance between images of 0.5–0.6 mm. We used the reference point of the lateral semicircular canal of each piece of temporal bone (axial cut parallel and coronal cut perpendicular to the lateral semicircular canal). No references were used in flat bones because of their irregular shape. For long bones, the axes of the cuts were directed parallel and perpendicular to the longitudinal axis of the bone.

We registered the variables evaluated by MDCT in a database. Images were tagged according to their characteristics, suggesting the presence of (1) mastoiditis; (2) coalescent mastoiditis; (3) mastoid occupation; (4) mastoid sinus compromise; (5) external extramastoid extension; (6) erosion in the epitympanum, mesotympanum, and hypotympanum; (7) ossicular chain; (8) dehiscence of the facial, anterior, posterior, and horizontal semicircular canal; (9) opacification of the anterior, posterior, and horizontal semicircular canal; (10) erosion, sclerosis, and occupation of the cochlea; (11) sclerosis of the petrous apex; and 12) erosion of the external auditory canal.

Incipient mastoiditis implies a periostitis without destruction of the bony septa, and coalescent mastoiditis refers to a bony erosion secondary to an osteitis that affects the bony mastoid septa or the mastoid cortex (Pastuszek et al. Reference Pastuszek, Lomas, Grigg and Ranit2020).

Phase 3.2: Ethnolinguistic and Historical Analysis

An ethnolinguistic analysis of La Relación de Michoacán was performed to document the relation of the identified pathologies with the social activities carried out by the fishing communities in the city of Tzintzuntzan at the time of Spanish contact (Alcalá Reference Alcalá2008 [1540]). La Relación de Michoacán describes how a group of hunters and warriors from the north encountered a territory in Lake Pátzcuaro inhabited by fishing communities. The newcomers intermarried with the daughters of these fishermen and learned how to fish in the lake. The union of the two groups led to the formation of a new community that would inhabit and dominate the territory for the following centuries (Paredes Reference Paredes2017; Warren Reference Warren1977).

Another important source is the ancient Purépecha-Spanish dictionary compiled by the Spanish friars during the sixteenth century (Warren Reference Warren1991). It contains many words to denote fishing activities, involving nets, hooks, and rods, as well as the use of canoes, swimming, and other activities that imply the need to submerge in the waters of the lake (Figure 2).

Results

A total of 96 temporal bone samples from two locations were reviewed: 80.32% were from the ossuary of Tzintzuntzan and 19.67% from La Zarzamora. Forty-one temporal bones (including the squamous, mastoid, and petrous parts) were analyzed osteologically and by photogrammetry. Of these, 30 (73.17%) were suitable for MDCT analysis,

Pathological changes were observed in 78 of the 96 analyzed bones (81.2%; Supplementary Table 1). Otitis media-related changes were observed in the erosion of the tympanic box, with the most frequent change being erosion of the hypotympanum, which was identified in 34.1% of samples. However, because of preservation factors, the involvement of the ossicles could not be evaluated. Notably, dehiscence of the anterior semicircular canal was observed more frequently than normal; it could be due to an anatomical condition not associated with an infectious process of the middle ear. (Figures 3 and 4; Supplementary Figures 3–8).

Petrositis is another pathology associated with middle ear infections, particularly noted in advanced stages of mastoiditis, as observed by the sclerosis of the petrous apex in these samples. In addition, changes compatible with probable external ear infections were observed (Table 1). Taphonomic differences were found in 29.63 % of the cases (Supplementary Table 1).

Figure 3.

Endocranial view of six temporal bones. Red arrows mark fistulous orifices located over the internal petro-squamous fissure with varying degrees of progression of the infectious process (a, b, d, e); in the petrous portion (c); and in the central lower portion of the squama (f). Photos by Miguel Ibarra and Paris Dávalos. (Color online)

Figure 4.

Ectocranial view of temporal bones. Arrows mark fistulas (c–e) and spicular formations located between the suprameatal crest and the supramastoid crest (e). There is an increase in the size of the internal cells of the mastoid (a and f) due to an inflammatory process. Temporal B corresponds to temporal d in Figure 5 and does not show a macroscopically visible lesion in this view. Photos by Miguel Ibarra and Paris Dávalos. (Color online)

Table 1.

Osteological and Photogrammetric 2D Analysis.

Up to 50% of the samples showed inflammatory changes related to mastoiditis, mainly represented by sclerosis. Additionally, opacification of the mastoid air cells, which is associated with the advanced stages of mastoiditis, was present in 43.33% of the samples. Extramastoid involvement was also observed in 46.67% of the samples, and 50% of the studied bones presented coalescent mastoiditis (Table 2; Figure 5).

Figure 5.

CT image depicting lesions associated with otitis and mastoiditis. (Color online)

Table 2.

Findings of MDCT Evaluation of the Temporal Bones.

Discussion

A high frequency of bone level changes associated with chronic otitis (34.1%) and mastoiditis (50%) was observed in the analyzed sample. Otitis and mastoiditis are diseases whose prevalence has decreased since the creation of antibiotics, dropping from 50% to 0.4% today (Flohr and Kierdorf Reference Flohr and Kierdorf2022; Pastuszek et al. Reference Pastuszek, Lomas, Grigg and Ranit2020).

MDCT of the temporal bone is important for the diagnosis of these two pathologies, particularly in ancient remains, because it allows the identification of advanced disease based on the condition of the middle ear and on changes in mastoid cell aeration (Pastuszek et al. Reference Pastuszek, Lomas, Grigg and Ranit2020. In this study we were able to identify lesions indicative of chronic otitis and mastoiditis in 70% of samples, based on the presence of erosions.

Several studies have reported the presence of diseases in the external auditory canal in Europe (Flohr and Kierdorf Reference Flohr and Kierdorf2022; Olivé-Busom et al. Reference Olivé-Busom, López-Costas, Quer-Agustí, Márquez-Grant and Kirchner2021). A study conducted in a Punic and Roman population of Cadiz, Spain, found chronic middle mastoiditis in 18% of women and 6% of men in a sample of 60 adult individuals, using conventional radiography and CT. The authors emphasize the difficulty of differentiating between otitis and mastoiditis, especially in samples from the pre-antibiotic era. The lack of treatment produces a pneumatization of the mastoids secondary to recurrent infections, leading to petrosal sclerosis that compromises the stapes; this process of otitis and mastoiditis can result in deafness (Macías et al. Reference Macías-López, Villanueava-Marcos, Mateo and Ruzapérez-Barquero2023).

We consistently found that otitis and mastoiditis occurred together and at a higher percentage than in the Spanish study: 50% of the sample showed signs of sclerosis in addition to the erosions, which indicates a higher probability of deafness in our sample. In contrast, we found a lower percentage of chronic mastoiditis (50%) than that reported by in an early Neolithic sample from Russia using CT (Purchase et al. Reference Purchase, Bazaliiskiib and Lieversec2019).

Castro et al. (Reference Castro, Goycoolea and Silva-Pinto2017) found otitis media in 54.6% of a sample of 542 temporal bones obtained from the coastal region of Chile. They concluded that the prevalence of exostosis of the external auditory canal is associated with cultural groups that performed aquatic activities as complementary subsistence measures to agricultural activities. That study’s findings of the frequency of ear and mastoid diseases (50%) and of otitis being a risk factor for deafness are very similar to ours; the bone samples analyzed were presumably from inhabitants of a coastal region, some of whom specialized in fishing activities. However, we did not observe exostosis in the analysis, perhaps because of the temperature difference between the cold sea water of the Chilean coasts and the warmer temperature of Lake Pátzcuaro. Therefore, these authors postulate the “aquatic thermal hypothesis” that explains the association between exostosis of the external auditory canal and repetitive contact with water at low temperatures (Castro et al. Reference Castro, Goycoolea and Silva-Pinto2017; Lorentz and Casa Reference Lorentz and Casa2021).

Bioarchaeology of Care Model

As mentioned earlier, the bioarchaeology of care approach contextualizes the analysis of human remains within experiences of illness and disability. In this study, we found that chronic otitis and mastoiditis can lead to hearing loss and thus produce a hearing disability, potentially characterized by limitations in language, cognitive development, and performance in general in daily life and in social relationships (Gremba Reference Gremba2020).

Given that the samples were obtained from a lakeside site, the interpretation of these lesions and the resulting pathologies must consider the significance of aquatic activities for a community such as the one that inhabited Lake Pátzcuaro. This model of the bioarchaeology of care and disability of ear disease can be constructed in stages as shown in Figure 6.

Figure 6.

Bioarchaeology of care model for ear disease and hearing impairment in a highly specialized fishing community (Tzintzuntzan, Michoacán, western Mexico). Images in Stage 1 obtained from field diaries of excavations in Tzintzuntzan, depicting the historical and archaeological context of the site. Images in Stage 3 obtained from La Relación de Michoacán, depicting the social and cultural organization of Tzintzuntzan, including the importance of aquatic activities and fishing. (Color online)

The first interpretation stage addressed the historical context of the archaeological sites. Previous excavations described Tzintzuntzan as a multiethnic and hierarchical community (Pollard Reference Pollard1977, Reference Pollard, Sanders, Mastache and Cobean2003, Reference Pollard, Williams and Esparza2009; Punzo-Díaz and Navarro Reference Punzo-Díaz and Navarro2022). For sustenance, the inhabitants combined fishing with hunting and agricultural activities in the surrounding forest. Exploitation of the aquatic resources of Lake Pátzcuaro was especially relevant for the organization of Tzintzuntzan society and for all the inhabitants of the area.

The second stage used different methods to conduct a paleopathological analysis of lesions and so established the probable diagnoses of chronic otitis and mastoiditis, possibly resulting in hearing loss or deafness. The integration of the different methods of analysis resulted in a more accurate description of the lesions.

This second stage was contextualized with an ethnolinguistic analysis of historical sources to show that these pathologies had clinical and functional interpretations and implications. In a Purépecha-Spanish dictionary, we found words to describe deafness (pacandini) and an ear infection (having a rotten ear, terendini) in the Purépecha language of the sixteenth century (Warren Reference Warren1991). Other interesting words are thinthinandin’stani (buzzing in the ear), vendini (something coming out of the ear), mipandini (blocked ear), yerequatahenani (vertigo), and tipah (to have severe pain). All these words describe symptomatology associated with inflammatory processes of the ear. Additionally, mitandicuhpenstáni (person whose ear is blocked) and mitzandicuhpenstani (recovering from deafness) potentially indicate the existence of a process of healing or some medical procedure (otologic surgery) that has not been documented in Mesoamerica (Alcalá Reference Alcalá2008 [1540]; Warren Reference Warren1991); however, these kinds of procedures were documented in northern Spain in the fourth century cal BC (Díaz-Navarro et al. Reference Díaz-Navarro, Tejedor-Rodríguez, Arcusa-Magallón, Pastor-Vázquez, Santos-Pérez, Sánchez-Lite, Gibaja-Bao, García-González and Rojo-Guerra2022). Furthermore, the existence of specialized deputies who organized the different groups of fishermen—those using net fishing (uaruri) and others using hook fishing techniques (tararna)—indicates the importance of this activity in Tzintzuntzan society (Alcalá Reference Alcalá2008 [1540]).

In the third and fourth stages, we integrated ethnohistorical sources, such as La Relación de Michoacán and the images within, that document the social importance of fishing activities in the communities surrounding Lake Pátzcuaro (Alcalá Reference Alcalá2008 [1540]). Given this context, the high frequency of otitis and mastoiditis, especially in advanced stages that can lead to hearing loss and even deafness, produces a disability that limits social functioning and has sociocultural implications.

Deafness affects individual and social life, and the disability can be exacerbated by negative social attitudes and prejudices. In general, it adversely affects interpersonal communication, psychosocial well-being, quality of life, and independence, compromising the agency of individuals with this disability (Davis and Hoffman Reference Davis and Hoffman2019). Therefore, there is a need for care for people with hearing loss.

Deafness can have different impacts depending on the age at which it occurs. Children’s speech development and learning can be adversely affected, and adults can experience social isolation and stigmatization, abuse, depression, and difficulty in relationships; it can also affect their choice of occupation (Davis and Hoffman Reference Davis and Hoffman2019). Importantly, otitis and mastoiditis identified in ancient remains are stress markers associated with a context of deprivation or low socioeconomic level, as well as structural violence (Garrido Campos et al. Reference Campos, Astrid, Anselm Hindelang, De Carvalho, Urzua Finke Siqueira, Herrera and Radon2018; Gremba Reference Gremba2020). In Tzintzuntzan, historical sources show that fishermen were similarly socially and economically disadvantaged, even though they performed highly specialized activities necessary for survival.

Disability is a social construction of the restrictions produced by a physical limitation; thus, individuals with chronic damage to the hearing apparatus that causes partial or total hearing loss have a different understanding and interpretation of the lived world. Hearing impairment may result in a reconfiguration of the individual’s life and social interactions and the care that society may grant to these individuals. The bioarchaeology of disability (Bohling et al. Reference Bohling, Croucher and Buckberry2022) is an explanatory model that allows us to interpret the importance of hearing loss for individuals.

The relevance of a high frequency of otitis and mastoiditis in samples from different archaeological sites of a lake region—especially one as highly important to western Mexico as Tzintzuntzan—is determined by what this finding can reveal about the relationship between these pathologies and the activities of daily life. The existing literature has documented the frequency of infections that can produce these alterations and damage, especially in the pre-antibiotic period. However, little has been reported about other risk factors, such as those related to occupational hazards like aquatic immersion activities (Flohr and Schultz Reference Flohr and Schultz2009a).

Ethnolinguistic analysis, combined with bioarchaeological analysis and imaging, enabled an interpretive synthesis from the perspective of the bioarchaeology of care and disability. We started with the identification of a health problem—chronic otitis and mastoiditis that can lead to hearing loss—in the context of daily life activities—fishing in lakeside communities—to understand how prehispanic societies recognized and understood the presence of a disability. Not only did a word for a hearing disability exist in prehispanic times but also the very name “Michoacán” (the place where Tzintzuntzan is located) is Nahuatl for “land of fish,” highlighting the importance of water in the landscape and subsistence of these cultures (Williams Reference Williams2022).