Archeological Evidence for Dietary Use of Bigfoot Leopard Frog (Lithobates megapoda) in Postclassic and Colonial Central Mexico



Analysis of archaeofaunal remains recovered from several geographically and culturally linked postclassic sites in the Laguna de Magdalena Basin, Jalisco, Mexico, reveals that indigenous agrarian people of this area incorporated substantial quantities of the robust bigfoot leopard frog (Lithobates megapoda) (Taylor 1942) in their diet during both prehispanic and colonial occupations. Even though residents of this area combined hunting and fishing with cultivation of both native and colonially introduced flora and fauna, more frog remains were recovered than any other small species. Furthermore, it appears that exploitation of the frog was most intensive during the colonial occupation. As in modern cuisine, the hindlimbs were the preferred portion. Mortuary frog effigies suggest that the frog may also have had iconic value.


In the early 1960s a team of archeologists based at the University of California, Los Angeles (UCLA), excavated a cluster of sites in the Cuenca de Laguna de Magdalena or Etzatlán Basin of western central Mexico. This is the westernmost lake basin of the Mesa Central, located at an elevation of about 14 hundred meters (4,593 feet), about eighty kilometers (50 miles) west of Guadalajara and about one hundred kilometers (62 miles) east of the Pacific coast. Prehistorically and at the time of Spanish contact, numerous native communities were situated around the margins of an expansive lake and on islands within the lake (Figure 1). This lake was one of many volcanic endorheic freshwater sources in Central Mexico; that is, it was a closed drainage basin with no direct outflow, losing water only by evaporation and seepage.

Figure 1.

The Etzatlán Archeological Region.

Laguna de Magdalena has been pictured as extending from the present community of Etzatlán on the south to El Arenal on the north (Bell 1974, plate I accompanying Nicholson and Meighan 1974). In 1892, the lake was reported to have been about twenty miles long and several miles wide (Goldman 1951) and supported a thriving local fishery. Although the lake is now considered extinct (having been drained in the early 1900s) (Weigand 1985), residual stands of water in the basin currently provide habitat for some fish (Dominguez-Dominguez et al. 2007; Smith and Miller 1980) and aquatic birds (Williams 1982).

Early Spanish reports note that Etzatlán had an able-bodied adult male population of about six hundred. Weigand, however, estimates a much larger population, possibly several thousand individuals occupying several hundred hectares (Nance et al. n.d.).1 These people sustained themselves with a combination of hunting and fishing (Porcasi n.d.)2 along with cultivation of food staples. Corn, beans, squash, and peppers were an integral part of Mesoamerican lifeway at least two thousand years before the arrival of the Spanish explorers. Whitmore and Turner (2000) describe an even greater diversity of crops including specialized orchards of avocado, edible cacti, capulin cherry, and other fruits. Cotton was also cultivated for both clothing and trade purposes.

In earliest times agricultural activities were sedentary and egalitarian, but over time and with the addition of introduced (i.e., European) flora and fauna became more complex. Processing and transport of salt and minerals were also major economic factors for the Etzatlán community, and large quantities of obsidian were available to occupants of this area, particularly from Sierra de la Venta near Magdalena.

Although previously known by various other names (e.g., Icatlán, Yzatlán, or Izatlán), the political and economic importance of this area was recognized by the Spanish who constructed a major complex of buildings and fortifications at Etzatlán including a monumental ceremonial and administrative center (Templo/Convento de la Concepción) a modern manifestation of which still graces the city of Etzatlán.

The Etzatlán Basin has a lengthy but rather erratic history of archeological exploration and study (e.g., Bell 1974; Foster and Weigand 1985; Glassow 1967; Kelly 1945; Long 1966; Long and Taylor 1966; Nicholson 1962; Weigand 1974). These projects concentrated either on establishing ethnohistory or recording the traditional archeological treasures of prehispanic cultures: elaborately decorated ceramics and figurines and their typology, habitational or monumental structures, and elaborate tombs. These have given insight into many important aspects of the various cultural occupations of the area. Almost entirely lacking from the relevant literature, however, are details of the day-to-day subsistence activities of the people of the Etzatlán area either before or after the arrival of Spanish colonizers. Furthermore, only a few problematic radiocarbon dates taken from mortuary materials are available.

The Etzatlán sites excavated by the UCLA team produced a combined collection of scientifically significant mortuary artifacts, ceramic potsherds, and vertebrate remains. While the mortuary artifacts were documented with some approximate chronological control by Long (1966) and pottery from nearby Huistla was described by Glassow (1967), the majority of the ceramic potsherds and the faunal remains remained unstudied. That unfortunate situation is no longer true.

At present an ongoing statistical correspondence analysis (CA) of ceramic typology (Nance et al. n.d.)1 is using the ceramic collection to establish a cultural sequence for the area along a statistically derived, undated “timeline” that pinpoints a specific CA value (.4593) at which there is ceramic evidence for the onset of Spanish occupation. Concurrently with the ceramic analysis, the entire faunal collection has been analyzed and provides rare insight into subsistence patterns of both the prehispanic and the colonial populations (Porcasi n.d.).2 Along with patterns of prehispanic and colonial dietary transitions, this faunal analysis has revealed that a previously unreported frog (Lithobates megapoda, the bigfoot leopard frog) was an important portion of the diet during both occupations. These amphibians, which are among the largest frogs in the Americas, can attain a length well over twenty centimeters and a live weight of several hundred grams. They are native to the area and were readily available in the vicinity of Laguna de Magdelena and the marshes, rivers, and streams of the Mesa Central.

The Etzatlán Sites

The four sites constituting the primary Etzatlán dataset include Tiana, Anona, Santiaguito, and Las Cuevas. They cluster near the city of Etzatlán at the southern margin of the former lake. Santiaguito and Las Cuevas were situated on islands in the lake and had substantial permanent houses and populations of several hundred as recorded by the Spanish explorers. Anona, which was also identified in early historic reports, bordered the present-day city of Etzatlán. Location of the fourth community, Tiana, was not noted by the Spanish but may have been an earlier, possibly abandoned, settlement because the more recent ceramics types were not found there.

Materials and Methods

The four sites named above yielded a total of 1,617 vertebrate specimens with a total weight of 2,855.44 grams. These are shown in Table 1 in which specimens are quantified as Number of Identified Specimens, a non-analytical sum of the specimens for each taxon or more general category, and weight. During analysis, all faunal specimens were identified to the most detailed taxonomic level possible by direct comparison with museum-curated comparatives from the Los Angeles County Museum of Natural History (LACMNH) and the Zooarchaeology Laboratory of the Cotsen Institute of Archaeology at the UCLA.

Table 1. 
Faunal Remains Recovered from the Etzatlán Sitesa
SiteNISPWeight (g)
  • a

    Includes a small quantity (7) of specimens from non-stratigraphic proveniences such as burials or unit extensions.

  • NISP, Number of Identified Specimens.

Las Cuevas10541525.01

Overall, the dietary breadth of the occupants of the Etzatlán sites was quite narrow, consisting of artiodactyl (almost exclusively deer), a medium-sized canid (dog or coyote), native turkey, migratory and resident waterfowl, mud turtle, and the frog. Table 2 presents the relative percentages of these taxa during both prehispanic and historic occupations.

Table 2. 
Proportions of Taxa excavated from the Etzatlán Sites
Taxon/CategoryCommon NameNISP%
  • a

    Historically introduced taxon.

  • b

    b Excludes seven specimens from burials and unit extensions.

  • NISP, Number of Identified Specimens.

Aechmophorus occidentalisWestern grebe110.7
Anas carolinensisGreen-winged teal20.1
Anas creccaTeal70.4
Anas cyanopteraCinnamon teal10.06
Anas spp.Duck160.9
AvesUnidentified bird23514.6
Aythya AmericanaRedhead duck10.06
Bos TaurusaCow/steer442.73
Canis spp.Dog/coyote1378.51
ColubridaeColubrid snake30.2
Didelphis virginianaaOpossum90.6
Fulica AmericanaAmerican coot120.8
Kinosternon spp.Mud turtle774.78
Lepus spp.Hare60.4
Lithobates megapodaBigfoot leopard frog1026.34
MammalUnidentified mammal68842.73
Meleagris gallopavoTurkey543.35
Mustela frenataWeasel10.06
Odocoileus virginianusWhite-tailed deer392.42
Orthogeomys grandisGiant pocket gopher20.1
OsteichthyesBony fish80.5
Ovis ariesaSheep20.1
Podiceps nigricollisEared grebe20.1
Scaphiopus spp.Spadefoot toad30.2
SerpentesUnidentified snake10.06
Sylvilagus spp.Rabbit30.2
VertebrataUnident. vertebrate221.37
Total 1610b100.0

It should be noted that there is an unreasonable void of fishbone and other small taxa in the faunal collection. It is difficult to explain how sites directly associated with a large freshwater lake could produce such an archeofauna, especially because native fishing was reported by the first Spaniards to visit the area (Long 1966). Both the frog and a considerable number of turtle remains are evidence of exploitation of the peri-aquatic resource area. It is likely that the absence of most small bone in this collection is due to the fact that the midden was not screened during excavation (M. A. Glassow, personal communication 2007, Anthropology Department, University of California, Santa Barbara). Thus, the large quantity of frog bones is enigmatic. More frog remains were recovered than any other small species.

L. megapoda

The frog specimens were identified as L. megapoda (bigfoot leopard frog) by direct comparison with a whole body specimen obtained from the LACMNH and skeletonized by the author (Figure 2). Formerly identified as Rana megapoda, this ranid frog is a close relative of Rana catesbeiana, the familiar bullfrog of North America. It is notably larger, however. R. catesbeiana rarely exceeds 20 centimeters length and 230 grams live weight. L. megapoda is larger by as much as fifty percent, and might produce well over three hundred grams of flesh. There are, however, no comprehensive size or weight data published for this animal (Frost 2007; D. Frost, personal communication 2007). The comparative specimen (no. 37117) used in this research was an adult female approximately twenty-two centimeters long with an abdomen full of eggs. Weight was not ascertained because the animal had been submerged for almost three decades in a preservative solution and may have absorbed liquid weight.

Figure 2.

Los Angeles County Museum of Natural History Specimen No. 37117, Lithobates megapoda Before Dissection. (Small squares on scale are centimeters.)


Table 3 presents the quantities of bigfoot leopard frog remains at each of the Etzatlán sites and the proportion of the frog within each collection. There is an apparent sample size effect: the larger the total site collection, the greater the proportional presence of the frog. There is additional evidence that the preferred dietary portion of the frog was the hindlimbs (as in modern cuisine). Of the 102 specimens of this species recovered, 69 or nearly 68 percent were from the hind girdle, including the innominate (pelvis), femora, tibiae, and tarsals (Table 4). Because of its predominance and diagnostic character, the innominate was used to identify the taxon. Figure 3 illustrates several archeological specimens along with the comparative specimen. Many of the archeological specimens were larger than the adult comparative specimen, suggesting that the prehispanic and early historic animals might have been more robust than modern stock.

Table 3. 
Quantities of Lithobates megapoda Recovered from the Sites
SiteNISP% of Collection
  • a

    Seven specimens were from non-stratigraphic proveniences such as features or unit extensions.

  • NISP, Number of Identified Specimens.

Las Cuevasa848.0
Table 4. 
Anatomical Portions of Frog Remains
Anatomical PortionQuantityProportion (%)
  • a

    Includes one indeterminate limb shaft.

Axial skeleton
 Cranium (skull)87.8
 Innominate (pelvis)4241.2
Appendicular skeleton
 Forelimb (humerus, radio-ulna, scapula)2221.6
 Hindlimb (femur, tibia, tarsal)2726.5
Figure 3.

Archeological Lithobates megapoda Acetablum and Ilia Specimens (Dark-Colored Bone) and Museum Specimen 37117 (Light-colored bone). (Note the large size of the archeological specimen in the lower right corner.)


Both the stratigraphic positioning and the chronological association of the frog remains present meaningful patterns of prehispanic and colonial dietary use of this animal. Table 5 presents the stratigraphic deposition of recovered frog bones, exclusive of seven specimens recovered from features or unit extensions. Table 6 presents chronological association of the frog specimens based on the prehispanic-to-colonial timeframe developed in the ceramic CA (Nance et al. n.d.).1 It should be noted that not all recovered specimens are accounted for in Table 6 because the CA is based only on unit/levels that yielded a specified minimum number of potsherds of sufficient quality to establish their typology. Overall, the faunal collection used for the CA was 74 percent of the total collection. Furthermore, more prehispanic than colonial proveniences were used to establish the CA timeline. The nearly equivalent count of frog specimens in the colonial period (derived from fewer unit/levels with CA values), suggests increased use of this animal in the later occupation.

Table 5. 
Frog Specimens by Stratigraphic Level
Site (cm)120–140100–12080–10060–8040–6020–400–20Total
Las Cuevas1247392467
Table 6. 
Frog Specimens in Prehispanic and Colonial Occupational Contexts
Las Cuevas323668

The Frog in Cultural Context

In addition to its significant role in the diet, this frog may have had some iconic importance. Among the elaborate human figurines and highly decorated polychrome ceramics recovered from the tombs in and around Etzatlán and the lake basin, Long (1966) reported and pictured several meticulously carved frog effigy beads, some fashioned of green jade (Figure 4). Because these items were found in mortuary context and were made of fine materials they certainly had decorative value and might have had some symbolic worth as well.

Figure 4.

Two Green Jade Frog Effigy Beads from a Tomb near Etzatlán. (adapted from Long 1966.)

Other zoomorphic mortuary artifacts reported by Long (1966) were a small bird pendant of unstated material, a turtle-shaped clay ocarina, and a two-headed clay dog figurine. As noted from the faunal data, turtles, birds, and dogs were all important dietary elements in these communities. Perhaps this importance is reflected in the grave goods. Interestingly, however, the primary mammalian food source found at these sites (deer) is not represented in the mortuary artifacts in any manner.


Analysis of the faunal remains from four clustered postclassic sites in the Etzatlán Basin reveals an important and consistent use of dietary frog during both prehispanic and colonial occupations. The frog is the most common vertebrate recovered from the site, and its frequency might have been even more significant if the excavated midden had been screened to recover a greater collection of small specimens. There is evidence that the fleshy hindlimbs were the preferred portion of this animal. The frog may also have had some iconic importance in the prehispanic community.


I thank C. Roger Nance of UCLA for giving me the opportunity to study this archaeofaunal collection and for providing informative background on the ceramic CA. Brian Codding prepared the Figure 1 map.


  1. 1. Nance, Charles R., Jon de Leeuw, Paul C. Weigand, David Verity, and Kathy Prado N.D. Sequencing Ceramics from Etzatlán, Jalisco, Through Correspondence Analysis. Manuscript on file at the Cotsen Institute of Archaeology at UCLA, Los Angeles.

  2. 2. Porcasi, Judith F. N.D. Dietary Transitions at Postclassic and Colonial Sites in the Etzatlán Basin, Jalisco, Mexico. Manuscript on file with author and currently in review for publication.