Formant dispersion, the average spacing, in Hz, between the resonant frequencies of a vocalization, has been predicted to provide honest information about signaler body size. Previous descriptions of ...black and white colobus monkey (Colobus guereza, “guereza”) roars, however, suggest a formant dispersion that is far lower than expected for an animal its size, and could effectively exaggerate its body size. Nonetheless, recent research on red deer shows that even when the formant positions of vocalizations effectively exaggerate body size, they may still provide honest cues within a species. We investigate whether the frequency bands observed in the spectrograms of guereza roars represent formants, and whether roar formant dispersion and/or individual formants provide honest information about body size (specifically, body mass) relative to conspecifics, although perhaps not relative to other species. We document coordinated vertical movements in the frequency bands of guereza roars and show that these bands move independently of fundamental frequency, indicating that they represent formants. We show, for captive adult male guerezas, that signaler body mass significantly predicts roar formant dispersion, even for randomly selected calls. Body mass also predicts formants 2 and 3, but the relationships are not as strong as with formant dispersion. Our roar formant dispersion calculations predict a vocal tract length of approx. 29 cm, but anatomically determined guereza vocal tract length is much smaller: approx. 7–8 cm. Videotaped roars revealed no laryngeal movement during roars, but rather inflation of the subhyoid air sac. We measured the volume of this air sac (approx. 10 cm3) and speculate that it may function in roars to exaggerate body size, relative to other species.
Understanding the effects of variation in resource availability and habitat disturbance on the ecology of mammals is vital for successful conservation management. In this study, we examined how human ...disturbances, resource availability and elevation gradients influence mammal assemblages in both managed coffee forest and natural forest of the Belete-Gera National Forest Priority Area, southwestern Ethiopia. We surveyed mammals using motion-detecting infrared camera traps in 90 locations for a total of 4142 camera days. We measured distance from main roads and settlements as disturbance factors, and distance from water sources, key grazing sites, and forest edges and woody plant diversity as resource variables. We assessed the mammal assemblages in coffee forest and natural forests using generalized linear models. Further, we used linear modelling to compare the relationships of mammal detection rates by feeding guilds and body size to resource variables. In total, we recorded 8815 videos identifying 23 different mammal species. The mammal assemblages in coffee forests were negatively associated with increasing distances from key grazing sites, water sources, and elevation. In contrast, the association with increasing distance from the road and woody plant diversity was positive. In addition, herbivores and large (25–200 kg) and very large (≥200 kg) mammals, were all negatively associated with increasing distance from the natural forest edges. With the conversion of natural forest to coffee forest and the intensification of coffee forest management, sustainable management of key grazing sites, water sources, and diverse woody plant species will be essential to the conservation of mammals. In addition, to ensure mammal conservation, adjacent natural forests around coffee forests should also be protected.
Primates have adapted to numerous environments and lifestyles but very few species are native to high elevations. Here we investigated high-altitude adaptations in the gelada (Theropithecus gelada), ...a monkey endemic to the Ethiopian Plateau. We examined genome-wide variation in conjunction with measurements of haematological and morphological traits. Our new gelada reference genome is highly intact and assembled at chromosome-length levels. Unexpectedly, we identified a chromosomal polymorphism in geladas that could potentially contribute to reproductive barriers between populations. Compared with baboons at low altitude, we found that high-altitude geladas exhibit significantly expanded chest circumferences, potentially allowing for greater lung surface area for increased oxygen diffusion. We identified gelada-specific amino acid substitutions in the alpha-chain subunit of adult haemoglobin but found that gelada haemoglobin does not exhibit markedly altered oxygenation properties compared with lowland primates. We also found that geladas at high altitude do not exhibit elevated blood haemoglobin concentrations, in contrast to the normal acclimatization response to hypoxia in lowland primates. The absence of altitude-related polycythaemia suggests that geladas are able to sustain adequate tissue-oxygen delivery despite environmental hypoxia. Finally, we identified numerous genes and genomic regions exhibiting accelerated rates of evolution, as well as gene families exhibiting expansions in the gelada lineage, potentially reflecting altitude-related selection. Our findings lend insight into putative mechanisms of high-altitude adaptation while suggesting promising avenues for functional hypoxia research.
From March 1997 to February 1998, I investigated the activity patterns of 2 groups and the ranging patterns of 5 groups of eastern black-and-white colobus (Colobus guereza), aka guerezas, in the ...Kakamega Forest, Kenya. Guerezas at Kakamega spent more of their time resting than any other population of colobine monkeys studied to date. In addition, I recorded not one instance of intragroup aggression in 16,710 activity scan samples, providing preliminary evidence that intragroup contest competition may be rare or absent among guerezas at Kakamega. Mean daily path lengths ranged from 450 to 734 m, and home range area ranged from 12 to 20 ha, though home range area may have been underestimated for several of the study groups. Home range overlap was extensive with 49-83% of each group's range overlapped by the ranges of other groups. Despite the high level of home range overlap, the frequently entered areas (quadrats entered on ≥30% of a group's total study days) of any one group were not frequently entered by any other study group. Mean daily path length is not significantly correlated with levels of availability or consumption of any plant part item. Mean daily path length is also not significantly correlated with group size, though the largest group did have the longest mean daily path length. This finding suggests that intragroup scramble competition may have been rare or absent among guerezas at Kakamega except perhaps in the largest group, which was unusually large.PUBLICATION ABSTRACT
Bryobia abyssiniae Fashing & Ueckermann, a recently discovered species, is described using DNA-barcoding as well as morphological features of the adult female and all post-embryonic instars. The ...species is characterized by remarkable propodosomal lobe variation. A lack of variation in molecular markers indicates that the several forms observed reflect intraspecific variability in this apparently all-female species. Its host plant, a giant lobelia (Lobelia rhynchopetalum Hemsl.; Campanulaceae), is endemic to the Ethiopian highlands. A discussion of climate at the collection locality, the host plant, and notes on biology are also included. Additionally, we suggest that a minimum of 5% sequence difference in the mitochondrial cytochrome c oxidase subunit I region will be needed to differentiate Bryobia species.
Objectives
The birth process has been studied extensively in many human societies, yet little is known about this essential life history event in other primates. Here, we provide the most detailed ...account of behaviors surrounding birth for any wild nonhuman primate to date.
Materials and Methods
Over a recent ∼10‐year period, we directly observed 15 diurnal births (13 live births and 2 stillbirths) among geladas (Theropithecus gelada) at Guassa, Ethiopia. During each birth, we recorded the occurrence (or absence) of 16 periparturitional events, chosen for their potential to provide comparative evolutionary insights into the factors that shaped birth behaviors in humans and other primates.
Results
We found that several events (e.g., adopting standing crouched positions, delivering infants headfirst) occurred during all births, while other events (e.g., aiding the infant from the birth canal, licking infants following delivery, placentophagy) occurred during, or immediately after, most births. Moreover, multiparas (n = 9) were more likely than primiparas (n = 6) to (a) give birth later in the day, (b) isolate themselves from nearby conspecifics while giving birth, (c) aid the infant from the birth canal, and (d) consume the placenta.
Discussion
Our results suggest that prior maternal experience may contribute to greater competence or efficiency during the birth process. Moreover, face presentations (in which infants are born with their neck extended and their face appearing first, facing the mother) appear to be the norm for geladas. Lastly, malpresentations (in which infants are born in the occiput anterior position more typical of human infants) may be associated with increased mortality in this species. We compare the birth process in geladas to those in other primates (including humans) and discuss several key implications of our study for advancing understanding of obstetrics and the mechanism of labor in humans and nonhuman primates.
Compassionate behavior towards dying, diseased, or disabled individuals is often regarded as a uniquely human trait, though recent reports of reactions to death and dying in nonhuman animals ...highlight the value of adopting a comparative evolutionary approach toward these behaviors. Here, we review recent studies of animal behavior toward the dying, diseased, or disabled which may be of interest to paleopathologists and bioarchaeologists studying compassionate behavior in humans and their extinct ancestors. 'Compassionate' behavior toward the enfeebled and dying has now been reported in several non-primate mammals (e.g., wild African elephants and river otters) and nonhuman primates (primarily captive chimpanzees). In addition, a number of recent reports have documented wide variation in nonhuman primates' reactions to recently deceased group mates (or offspring) both across species, as well as across individuals belonging to the same social group. We suggest there is considerable potential for collaboration among paleopathologists and primatologists in examining the causes of illness and disability in animals and its impact on their lives.
