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The Hayonim Terrace small game fauna is dominated by high-ranked tortoises.
Hares and birds are also present, but in less significant numbers (see Figure 7.14). The emphasis on tortoises indicates that encounter rates with these animals were high, that exploitation was not excessive, and that humans could thus afford to rely mainly on this species for their small game needs. Overall, the small game proportions for the Terrace are very similar to those from the Late Natufian phase inside Hayonim Cave, but they are markedly different fi-om those of the Early Natufian in the cave (Figure 7.14). The only notable difference between the Late Natufian assemblages fi-om the Cave and Terrace concerns the proportion of birds, particularly partridges, which are much better represented inside the cave. This may be a result of differential preservation, because bird bones are thin-walled and hollow, and thus more susceptible to crushing in the concreted sediments on the Terrace than in the soft deposits inside the cave.
Bar-Yosef and Belfer-Cohen (n.d.) use archaeological indicators to argue that Late Natufian occupation on the Terrace was shorter than the occupation in the Cave.
They cite the absence of slab-lined floors and built-up hearths on the Terrace as an indication of reduced energetic investment into architectural features. Still, the Terrace is interesting because it contains several features associated with Natufian "base camps", including burials, heavy grinding stones, and fragments of stone walls backed into the natural slope of the terrace (Valla et al. 1991). Affinities in the relative proportions of
Hayonim Cave suggest that the intensity of use of the two areas was similar. Whether or not Hayonim Cave and Terrace were one site or two, it is clear that Late Natufian occupations in both locations were significantly less intensive than the Early Natufian occupations inside the Cave. Equivalence in the proportions of small fauna types from the Late Natufian in the Cave and on the Terrace indicates similar subsistence requirements and foraging conditions in both areas during this phase.
The small game proportions fi-om the Late Natufian site of Hilazon Tachtit indicate that its inhabitants were the least constrained hunters of all. Of the sites sampled, Hilazon Tachtit yielded the highest proportions of tortoises, which constitute 86% of the small game types consumed there. The only other major prey type in the assemblage is gazelle, another high-ranked species. The types of game selected by the hunters that occupied Hilazon Tachtit suggest that the site was occupied only sporadically by small groups, and that the environment around the site was not so depleted of highranked resources that local demand could not be met.
Hilazon Tachtit is a small cave site with two circular structures (loci), constructed from low stone walls (Leore Grosman, personal communication 2001). Ornaments and artwork are present, but uncommon, and groundstone and bone tool assemblages are restricted to the more basic types (mortars and pestles, awls, gorgets, and sickle hafls).
The site is rich, however, in primary and secondary burials, and the abundance of human remains raises questions about the ritual significance of the site. Was it a burial center to which humans came to inter their dead? The presence of so many human burials
faunal assemblages also provide evidence for a full range of economic activities (see Chapter 5; Grosman n.d.). Hilazon Tachtit was a small Late Natufian base camp by the standard definition. The small game index corroborates the evidence for light, sporadic occupation.
In general, the largest Natufian sites with the greatest investment in site features have the highest proportion of highly-rar\ked small game animals (tortoise), indicating intensive use of the site and the surrounding environment. They are also the earliest Natufian sites in the Mediterranean Hills. The shift away firom diets rich in low-ranked
resources to those emphasizing more high-ranked species correlates strongly with time:
the largest sites in the sample were occupied in the Early Natufian, the more ephemeral sites date to the Late Natufian phase. Though the small game index predicts relative site occupation intensity, the temporal trend must eventually be tested by including sites from outside the Mediterranean zone. Despite this qualification, it is appropriate to explore broader temporal trends in Natufian subsistence and demography on the basis of the faunal evidence (see Chapter 9). Before taking this final interpretive step, I use another line of evidence, the age structures of high-ranked prey (see Chapter 8), to examine the
Over the past four decades, mortality profiles have been adopted by archaeozoologists as a tool to solve a diverse range of problems. Effective methods have been proposed to answer questions on subjects ranging from human hunting strategies and preferences (i.e., scavenging versus hunting) to seasonality and resource depletion (e.g., Klein 1982; Lyman 1987; Stiner 1990, 1991, 1994). Most studies have been aimed at reconstructing human hunting behavior in particular. This requires the separation of the original living age structure of the prey population from the mortality profile potentially created by human hunting decisions, and subsequently deposited in the archaeological record. This discussion focuses not so much on mortality profiles as it does on simulating variation in the living age structure of populations from which prey were originally hunted. The ultimate goal is to gauge the intensity of human hunting pressure. To do so, nonetheless we must define the range of natural variability in prey living age structures, identify the expected outcome of human hunting pressure on prey populations, and pinpoint potential confounding influences (i.e., hunting strategies and preferences, and season of capture), and their anticipated effects on prey mortality profiles (Stiner 1990; 1994: 271-287).
biology, where the method is widely employed, particularly within the context of game management and conservation (i.e., Riney 1982; Solbrig and Solbrig 1979; Taber et al.
1982). Though less commonly applied in archaeological contexts, a few studies focus on the impact of hunting pressure on ungulate age structures (Broughton 1994; Davis 1983;
Elder 1965; Lyman 1987; Koike and Ohtaishi 1985, 1987; Stiner 1990, 1994; Wolverton 2001). Most archaeological studies use life tables or living age structures of modem prey populations subjected to known hunting pressures, as analogues to interpret age profiles generated from archaeozoological assemblages. This research follows similar methods.
The discussion begins by outlining the range of natural variation in prey living age structures. The simulations introduced in Chapter 6 illustrated the impact of population growth rates and seasonal reproduction on the age composition of living prey populations. They also illustrated the potential impacts of human hunting behavior on prey living structures and archaeological mortality profiles. The expectations from predator-prey simulation modeling are now applied to the mortality profiles of archaeological prey to interpret the intensity of human hunting pressure during the Natufian period. Age profiles from the Middle and Upper Paleolithic Levant set the Natufian into evolutionary context, followed by a detailed examination of the Natufian period itself
VARIATION IN LIVING POPULATION STRUCTURES OF PREYThe living age structures of animal populations can vary from season to season or
concept is a static representation of one instant in a dynamic population cycle, and provides only a glimpse of a population's age structure at any given time. In reality, population structure is under continual adjustment to internal and external variables, though it normally varies within predictable limits. The expected range of natural variation in prey population structures is reviewed below.
The living age structure of a stable vertebrate population display a step-like pattern in 2-D graphic format, descending from the youngest to the oldest age group in the population (Figures 8.1 and 8.2). The number of animals in a particular cohort is highest immediately after birth and diminishes over time as individuals succumb to a variety of mortality agents. Stable populations are at equilibrium, thus fertility and mortality rates are entirely complementary to one another, and the ratios among age cohorts remain constant through time (Caughley 1966, 1977). Despite great variation in reproductive strategies, the same basic population structure defines most or all vertebrate populations at equilibrium. This point is illustrated by the stable populations generated by the tortoise LGM (Figure 8.1) and the hare HGM (Figure 8.2) simulations, an exercise with strong empirical components. Despite differences between tortoises and hares in population parameters and the absolute ages of the cohorts, the stable structure of the two populations are virtually identical.
Although all stable population structures display the same basic pattern, the relative sizes of the steps in the age pyramid (the steepness of the slope) and thus the ratio of juveniles to adults in a population can shift if the system is destabilized in any way.
modem ecological studies are instructive here: the most influential factors relevant in this study include seasonality and the rate of population growth.
Figure 8.1: Age structure of a stable population under low growth conditions.
Population created using the tortoise LGM parameters. Simulation was run at equilibrium for 200 years. Three runs were averaged to eliminate random variation.
The Effect of Seasonality on Prey Living Structures The aduhs of many animal species are reproductively active for only short periods each year. The young of these species are usually bom in correspondingly restricted periods. The proportion of juveniles is thus highest immediately following the birth season, and then gradually declines until the cycle begins again. The impact of seasonally restricted reproduction on an animal population structure is illustrated by tracking monthly changes in the proportions of juveniles in a modem gazelle population from Ramat Qedesh in Israel. Mountain gazelles are seasonal breeders with one or two reproductive peaks per annum, depending on the favorability of conditions (Ayal and Baharav 1983; Baharav 1974, 1983a, 1983b). Gazelle populations in the Levant today, bear the majority of their young in late spring/early summer. The proportion of juveniles thus peaks first in early summer and occasionally a second time in early autumn, if conditions allow. The percentage of juveniles in the populations then gradually declines over the remainder of the year, reaching a low in spring just prior to the next reproductive season (Baharav 1974, 1983b).
Figure 8.3 illustrates variation in the proportion of juvenile gazelles in the Ramat Qedesh population over the course of three years (data adapted from Table 1 in Baharav 1983b).
There was strong seasonal variation in the proportion of juveniles in the population ranging from 14.5 to 39.6% in 1975, and between 15.1% and 29.9% in 1976.
Though other influences including population movements also have some influence over
Figure 83: Bimonthly fluctuations in the proportion of juveniles in a population of mountain gazelles from Ramat Qedesh in Israel. Data from Baharav (1983b, Table 1).
As illustrated by the Ramat Qedesh gazelles, restricted reproductive seasons can cause fluctuations in a population's age composition throughout the year. Clearly an hunting a prey population in its natural proportions in winter would produce a different mortality profile than one collected in the summer. Seasonal birth patterns may have a significant impact on prey mortality profiles, particularly in hunted assemblages that are collected at restricted times of the year. Their signatures can thus be confounded with those resulting from human hunting strategies that favor the collection of specific age groups. The archaeological record averages this effect to a large extent in many situations. The length of stay is already interpreted to vary between phases of the Natufian, however, thus seasonal explanations must be considered when evaluating
The Effect of Population Growth Rate on Prey Living Structures Shifts in the relation between rates of fertility and mortality can also create fluctuations in population age structures. When mortality rates increase, the population may drop below carrying capacity and responds by shifting into growth mode, leading to inflation of the proportion of juveniles. The living structure of a growing population is thus concentrated on the younger age of the age axis in the typical 2-D graph, with a steep slope and lower mean and maximum ages in comparison to a stable population (Figure 8.4). The living structure of a typical growing population (Figure 8.4) was created by increasing the armual rate of mortality in the hare HGM simulation after that population had reached equilibrium.
Figure 8.5 Age structure of the same outset population as in Figure 8.
4, as it shrinks. Population created using parameters for the HGM hare simulation. Age structure created by reducing the number of babies produced per female each year so that mortality exceeded fertility. The population was allowed to shrink for a few years before the age structure was determined.