Fossil remains of Macaca sylvanus florentina (Cocchi, 1872) (Primates, Cercopithecidae) from the Early Pleistocene of Quibas (Murcia, Spain)

The macaque material from the Early Pleistocene site of Quibas (Albanilla, Murcia, Spain), including dentognathic remains, isolated teeth and some postcranial bone fragments, is described. Both metrically and morphologically, this sample must be attributed to Macaca sylvanus (the Barbary macaque). This species is currently distributed through North Africa and Gibraltar, but was much more widely distributed during the Plio-Pleistocene, being represented by several European fossil subspecies. Metrical comparisons of dental size and proportions between extant M. s. sylvanus and fossil Macaca sylvanus florentina from the type locality and other Italian sites are undertaken, in order to classify the remains from Quibas at the subspecies level. The results show that the Quibas sample not only fits the range of variation of M. s. florentina from the type locality, but also differs from the extant Barbary macaque condition in several regards. This permits us to formally attribute the material from Quibas to M. s. florentina. The material described in this paper therefore significantly improves the knowledge of this fossil taxon, particularly regarding the upper dentition, and further confirms the taxonomic distinctiveness of this extinct taxon at the subspecies rank. Taken as a whole, M. s. florentina largely overlaps in dental dimensions with M. s. sylvanus, but differs from the latter by displaying (on average): (1) absolutely longer upper molars (especially M¹ and M³); (2) relatively wider upper molars (especially M¹ and M²); (3) longer M³ as compared with the M²; (4) absolutely longer M₁ and M₃; and (5) relatively narrower M₃.     

Intergroup transfer and incest avoidance in semifree-ranging barbary macaques (Macaca sylvanus) at Salem (FRG)

During a long-term study of social behavior of semifree-ranging Barbary macaques, data on group transfer and sexual behavior were collected. A large population containing five groups living in a 14.5 ha outdoor enclosure was studied. Demographic data on the whole population are available for a period of six years. Data on sexual behavior of members of one large group were collected, by both focal animal and ad libitum techniques, for a period of two years. Matrilineal kinship relations of all except the oldest members of this intensively studied group were known. Males changed groups most frequently between the ages of three and five years i.e., the time at which sexual maturity was reached. While more than 30% of all males three years old and older changed groups during the study period, many males remained members of their natal group even after reaching adulthood. However, sexual interactions, especially matings between close matrilineal relatives, were found to be almost absent, suggesting that Barbary macaques are not highly inbred as formerly supposed.     

Comparative density,demography, and ranging behavior of Barbary macaques (Macaca sylvanus) in marginal and prime conifer habitats

A semiisolated study population of 162 Barbary macaques (six groups) inhabiting the Ghomaran fir forests of the Moroccan Rif mountains has a density of 6.73 individuals/km ². The adult sex ratio is 0.725, and immatures comprise 46.9% of the population. Births are seasonal, occurring from April to June, and the adult female birth rate is 0.58 per annum. Mortality appears relatively low in all age classes until old age. Group size ranges from 12 to 59 individuals, with a median value of 24. Home-range sizes vary between 3 and 9 km², with a mean of 7.2 km². Home-range overlap is approximately 80%. On the basis of macaque density, conifer density, and herding competition from domestic animals, the Ghomaran environment can be considered “marginal” compared to the Moyen Atlas. Despite the marginal habitat of the Ghomaran population, it is surprisingly similar in demographic characteristics to a Barbary macaque population in the Moyen Atlas. Two characteristics of the population dynamics in the Ghomara differentiate it from the former. (1) The mean home range is five times larger in the Ghomara, roughly inversely proportional to the sixfold decrease in macaque density, confirming Caldecott’s (1986) principle that, in macaque species, range size adjustments are a primary proximate response to poor-quality habitat. (2) Smaller groups in the marginal habitat of the Ghomara appear to have better rates of growth than small groups in prime habitat. This may result from an overall decreased home-range defensibility in marginal habitat (larger home ranges), resulting in an ecological and demographic release of small groups from the levels of intergroup competition they would normally experience in prime habitat.     

The social position of male Barbary macaques (Macaca sylvanus) in a semifree-ranging population

A study was carried out on the social position of 12 subadult males of a semifreeranging Barbary macaque population during the non-mating season. The social position was measured in terms of spatial as well as interactive parameters. The subadult males had social contacts to members of nearly all other age-sex classes but showed clear preferences for same-sexed partners. Besides this differences were found between 5- and 6-year-old males with respect to their interaction profiles and the preference for special classes of interaction partners. The terms “peripheral-central” is discussed with reference to the social structures of macaque societies. The data of the present study indicate that the social position of subadult male Barbary macaques can not be described by one of these terms exclusively. The results are compared to other studies on Barbary macaques and other macaque species. It is concluded that in macaque societies subadult males are not obligatorily forced to live at the periphery or to abide. It is proposed not to postulate stiff social structures but to put more emphasis on the range of variation among macaque species.     

Male intergroup mobility in a wild population of the Barbary macaque (Macaca sylvanus), Ghomaran rif mountains,Morocco

In this two-year study of a Barbary macaque population (n = 162) in the Ghomaran region of Morocco, 13 cases of males separated from their assumed natal groups were observed (nine visits of nonresident males to groups, two males isolated from groups as much as one day and one night, and two sets of snow tracks indicating males travel +7 km as isolates). Males left their assumed natal groups primarily in the mating season (12 cases), focused their interactions on estrous females of other groups, and were observed to copulate with these females in two cases. All males leaving their assumed natal groups were estimated to be between 5 and 8 years of age, with one exception (+ 15 years). It could not be determined whether males younger than 5 years moved between groups, or whether any males made permanent intergroup transfers. Regardless, the data from this study indicate that male intergroup mobility (and intergroup gene flow) was higher than has been previously assumed for this species. A prior theory that Barbary macaque groups are highly inbred, and that this is causally related to the evolution of male-infant care in this species, is not supported by the data of this study.     

Female Barbary macaque (Macaca sylvanus) copulation calls do not reveal the fertile phase but influence mating outcome

In a number of primate species, females utter loud and distinctive calls during mating. Here we aim to clarify the information content and function of Barbary macaque (Macaca sylvanus) copulation calls by testing (i) whether or not copulation calls advertise the female fertile phase and (ii) whether and how copulation calls influence male ejaculatory behaviour. In order to do this, we combined hormone measurements with acoustic analysis and behavioural observations. In contrast to a previous study implying that the structure of copulation calls indicates the timing of the fertile phase, our results, using objective endocrine criteria for assessing ovulation, provide evidence that the structure of copulation calls of female Barbary macaques does not reveal the timing of the fertile phase. More importantly, females seem to influence the likelihood of ejaculation by calling versus remaining silent and by adjusting the timing of call onset. Females make use of this ability to influence mating outcome to ensure ejaculatory matings with almost all males in the group. In addition, calls given during ejaculatory copulations differ from those during non-ejaculatory copulations, providing information about mating outcome for listeners. We conclude that in this species, copulation calls apparently serve to enhance sperm competition and maximize paternity confusion.     

Group fission in a semifree-ranging population of Barbary macaques (Macaca sylvanus)

During a 16-month study of semifree-ranging Barbary macaques (Macaca sylvanus) the group under observation divided into two groups. Observations were carried out in 1987–1988, at «La Montagne des Singes,” Kintzheim, France. A subgroup of monkeys, which was already cohesive at the beginning of the study, became progressively autonomous in relation to the rest of the main group, during the mating season. Overt aggression between the males of the two groups during this period brought about the fission. Only low-ranking genealogies left their group of origin. Dominance relations between females remained identical in both groups except for one lineage. The alpha male and the alpha female of the subgroup had a close relationship before the fission occurred. The sequence of agonistic intergroup relations is described and analyzed in relation to male sexual competition and female alliance power. The results suggest that: (1) the males of the subgroup instigated the fission because it was the best strategy for them to counter sexual competition; and (2) the females followed the males in order to maintain their alliance network, necessary to insure their dominance status over subordinate females.     

Sexual behavior of wild Barbary macaque males (Macaca sylvanus)

Recent assertions that the Barbary macaque (Macaca sylvanus) is a multiple-or serial-mounting species are incorrect. Data are presented from over 300 copulations observed among wild Moroccan Barbary macaques which establish empirically that males of this macaque species are single mounters. The average length of an ejaculatory copulation was 8.7 sec, with a range of 6 to 14 sec. Ejaculation occurred an average of 6.3 sec after mounting, with an average of nine pelvic thrusts per ejaculation. Males appeared capable of ejaculating twice within 16 min, and three consecutive times within 37 min. Characteristically, only one mount and ejaculation occurred during a sexual association between an estrous female and each of her consorting males. Schemes of macaque evolution which incorrectly classify Barbary macaques as a multiple-mounting species should be viewed cautiously.     

Maternal discrimination of offspring vocalizations in Barbary macaques (Macaca sylvanus)

The response of Barbary macaque (Macaca sylvanus) females to vocalizations of their offspring was studied in a semi-free ranging population. The results of both facal observations and playback experiments demonstrated that mothers preferentially turned to their offspring's vocalizations over those of other young, providing evidence that mothers are able to recognize their offspring by acoustic signals alone. We assume that they may use this ability to monitor their infants' activities.     

Male Migration in Barbary Macaques (Macaca sylvanus) at Affenberg Salem

We analyzed male migration during a 20-year period in the free-ranging Barbary macaque population of Affenberg Salem. Most natal migrations occurred around puberty, but only one third of all males left the natal group. Secondary group transfers were rare. All males immediately transferred to other bisexual groups. Migration rates were highest during periods with high adult female/male ratios within social groups. Immigrants highly preferred groups with fewer males of their own age than in the natal group, and many males immigrated into groups that had no male their own age. These groups originated from a skewed distribution of resident males during group fissions. A comparison of emigrants with their natal peers supports the inbreeding avoidance hypothesis as cause of emigration rather than the male competition avoidance hypothesis. Emigrants had no lower individual rank position and did not come from lower-ranking matrilines. Emigrants had more female maternal relatives, especially sisters. Males without female relatives almost never emigrated. Conversely, there is virtually no indication that emigrants were evicted from the natal group. Emigrants had no increased mortality. Paternity data revealed that the reproductive success of emigrants and natal males is similar, indicating that emigration had no reproductive cost. Many similarities between emigrants and natal males that separated from female maternal kin during group fissions suggest that inner migration during fissions is an alternative way to avoid maternal inbreeding. The mating system resulted in a genetic structure within social groups that largely diminished the chances for paternal inbreeding even without recognizing paternal kin.     

Patterns of anogenital swelling size and their endocrine correlates during ovulatory cycles and early pregnancy in free-ranging barbary macaques (Macaca sylvanus) of Gibraltar

In macaques and other cercopithecoid primates, large anogenital swellings (AS) are generally found only in those species in which reproduction is not seasonally restricted. In this respect, the Barbary macaque is unusual because while it shows a marked degree of reproductive seasonality, it also exhibits a striking, exaggerated swelling of the circumanal region and labia. Information on the characteristics of AS in female Barbary macaques is limited in that it is largely based on semiquantitative assessments of swelling size, and there are no data on endocrine parameters associated with AS during ovulatory cycles or early pregnancy. In the present study, we combined quantitative measurements of four swelling size parameters (AS width, height, and depth, and labial width) using a video-imaging technique with fecal estrogen and progestagen determinations in free-ranging females of the Gibraltar Barbary macaque population to 1) characterize the pattern of AS throughout the mating season and early gestation, and 2) examine the relationships among changes in swelling size and endocrine parameters. The patterns of all four swelling parameters correlated significantly with one another, although measures of AS depth and labial width were difficult to obtain. Using the product of AS height and width, the data demonstrate that the occurrence of AS is highly seasonal, with pronounced cyclical changes during the mating season and early pregnancy. Furthermore, the swelling cycles are characterized by progressive size increases from the early to the late follicular phase, in association with an elevated estrogen:progestagen (E:P) ratio, with ovulation occurring during the maximum swelling phase. The results also demonstrated a conspicuous postconception increase in swelling between days 18-30 of gestation. The postconception swellings were on average 80% of the size of that of the conception cycles, and were preceded by a large increase in fecal estrogen levels and the E:P ratio. This is the first study to characterize swelling patterns and their endocrine correlates during ovarian cycles and early pregnancy in naturally reproducing female Barbary macaques. The data provide a solid basis for further studies to explore sociosexual behavioral patterns and the functional significance of AS in this species.     

A new Late Pleistocene non-anthropogenic vertebrate assemblage from the northern Iberian Peninsula: Artazu VII (Arrasate,Basque Country)

Late Pleistocene palaeontological sites without human intervention are limited in the Cantabrian region, and even more so those with a good state of preservation and rich biodiversity. A new vertebrate fossiliferous locality discovered at Kobate Quarry (Arrasate, northern Iberian Peninsula) is presented in this article. This site, in which remains of 40 different vertebrate taxa were accumulated, acted as a natural trap. The preliminary vertebrate faunal list includes five amphibian taxa, four reptiles, seven species of birds and 24 mammalian taxa. While small mammals are represented by 13 small mammal taxa (seven in the Order Rodentia, five in the Order Eulipotyphla, and one in the Order Chiroptera), the large mammal fauna comprises eleven species, including ungulates and carnivores. The palaeoecology inferred from this faunal assemblage suggests the existence of large forested areas with some grassland and a watercourse nearby, within a notably warm and humid climate. These palaeoenvironmental conditions, combined with AMS and AAR results carried out in macrofaunal bone samples, suggest that the deposit from Artazu VII would be located in the first half of the Late Pleistocene, in the Marine Isotope Stage (MIS) 5c.     

Dynamics of fission in a wild Barbary macaque group (Macaca sylvanus)

We studied the dynamics of a group of Barbary macaques (Macaca sylvanus) in Algeria from March 1983 to November 1989. Troop fission began in autumn 1987, when group size had more than doubled, to include 76 animals. We observed 11 temporary splits of this group during the mating seasons of 1987 and 1988. The process was interrupted during the 1988 birth season. In June 1989, fission resumed and ended with the formation of three independent groups that included 50, 24, and 13 individuals. Adult females played an important role in the process of fission. They initiated the rapid formation of two, and later three, coherent nuclei, distributed in two or three bisexual subgroups; on several occasions these nuclei also formed subgroups without any adult males. Adult males remained together in a single nucleus for longer periods of time than females did. However, during fission, 35% (N=20) of resident males emigrated to neighboring groups, while 11 strange males immigrated into the focal group; over 6 years, 57% of the male transfers occurred after the beginning of the process. After group fission, maternally related individuals lived together in the new groups. The majority of resident males remained with the largest of the three groups, while most of the immigrant males were in another group. The third group included a single adult male. Possible factors that induce group fission are discussed.     

First macroflora data from La Val (Late Oligocene/Early Miocene), Estadilla (Huesca,Spain)

This paper reports a previously unknown leaf-flora from the Upper Oligocene/Lower Miocene of the Ebro Basin, NE Spain, a period with a relatively poor vascular-plant fossil record in Southern Europe. The presence of Acrostichum sp. is also important. This fern is extremely significant from the point of view of palaeoecology and the depositional environment. The macroflora appears to yield sufficient morphological characteristics to be identified at genus level, and sometimes at species level, although cuticles are not preserved. This article presents the first data obtained from the new outcrop at La Val; the following families have been identified: Pteridaceae, Dennstaedtiaceae, Equisetaceae, Pinaceae, Lauraceae, Hamamelidaceae, Betulaceae, Myricaceae and Salicaceae. The fossil plant assemblage is correlated with the Cadibona floristic complex (Mai, Tertiäre Vegetationsgeschichte Europas. Methoden und Ergebnisse, Gustav Fischer, Jena, 691 pp., 1995) and suggests a subtropical-to-warm temperate climate, rainy and wet, with a short dry season. The age of the assemblage is Late Oligocene/Early Miocene.