Age-Sex Analysis of Activity Budget,Diet, and Positional Behavior in <Emphasis Type="Italic">Alouatta caraya</Emphasis> in an Orchard Forest

Howlers (Alouatta spp.) spend more than half of the daytime resting and their diet consists predominantly of leaves. Associated with a general strategy of energy conservation, their positional behavior is characterized by quadrupedalism as the major locomotor mode, and sitting as the most common resting and feeding posture. However, researchers have sparse information on the degree to which age-sex classes fit the generic trends and the influence of habitat structure on them. We compare the activity budget, dietary composition, and positional behavior by age-sex or age classes in a group of black-and-gold howlers (Alouatta caraya) in a small orchard forest. We collected 26,474 behavioral records via instantaneous scan sampling over 1 yr. The main activity was resting (56%) and the diet comprised mainly leaves (82%); sitting was the most adopted feeding (61%) and resting (52%) posture, and walking was the most prevalent locomotor mode (38%). There are age-sex differences for all major behaviors. Whereas resting tended to increase with body size, moving decreased. We observed no difference in the consumption of major plant parts. There were ontogenetic differences in most positional behaviors. Sitting increased from infants to adults during feeding, whereas the opposite occurred for bridging and hanging. During resting, infants curled more and lay less than the other classes did, whereas adults engaged in more sitting. Adults and subadults walked more than individuals of other ages did; infants climbed and bridged more than others did; and, there were opposing trends in leaping and descending. Habitat structure is a partial explanation of the locomotor behavior of black-and-gold howlers.     

Aerodynamic advantages of upside down take-off for aerial dispersal in <Emphasis Type="Italic">Tetranychus</Emphasis> spider mites

Aerial dispersal may be important for redistribution of spider mites into new habitats. Evidence for behavioral control of aerial take-off has been well documented for Tetranychus urticae Koch. Before aerial dispersal they exhibit the aerial take-off posture that involves lifting the forelegs upright and raising the forebody. However, whether the aerial take-off posture functions to increase drag has remained unclear. The objectives of this study were to clarify: (i) aerodynamic effects of the aerial take-off posture; and (ii) actual aerial take-off behavior in T. urticae. To evaluate the aerodynamic forces experienced by grounded spider mites in different postures, we constructed three-dimensional models of T. urticae, exhibiting the aerial take-off posture and the normal posture, using computer graphics. We found that the aerial take-off posture was effective in receiving greater rearward forces from wind rather than upward forces. As a result, aerial take-off from a horizontal platform is unlikely. Instead, inverted departure surfaces, e.g., lower leaf surfaces, with inclines are likely to be effective sites for take-off. Laboratory experiments and field observations indicated that the mites preferentially adopted such a position for orientation and take-off. Our findings provided a rationale for the take-off behavior of Tetranychus spider mites.     

Cicada acoustic communication: potential sound partitioning in a multispecies community from Mexico (Hemiptera: Cicadomorpha: Cicadidae)

Multispecies cicada communities in neotropical rainforests produce a complex and intense acoustic environment. In a fragment of a Mexican rainforest (Veracruz, Mexico), a cicada community at the end of the dry season consisted of nine species ( Daza montezuma; Pacarina schumanni; Miranha imbellis; Dorisiana sutori; Fidicinoides picea; Fidicinoides pronoe; Quesada gigas; one species of the genus Neocicada and one uncaught canopy species). Seven of the nine species formed dense choruses at dawn and at dusk. Each species showed preferences in the height of calling sites. Males of the species were solitary or gregarious, and followed a 'call-fly' or a 'call-stay' calling strategy. Acoustic signals of each species had particular time and frequency patterns. All these specific features appear to separate the nine species acoustically and lead to a partitioning of the acoustic environment. The acoustic partitioning might decrease the risk of heterospecific courting and mating.© 2002 The Linnean Society of London, Biological Journal of the Linnean Society , 2002, 75 , 379–394.     

Behavioral and reproductive effects of ultrasound on the Indian meal moth, Plodia interpunctella

The daily activity patterns of adult movement, female calling, and mating of the Indian meal moth, Plodia interpunctella (Hübner) (Lepidoptera: Pyralidae), were examined both in the absence and presence of ultrasound. Moths were exposed to ultrasound from a commercial ultrasonic device (Cix 0600) that produces constant sound patterns, and from a device developed at Kansas State University (KSU device) that produces random sound patterns. Daily activity patterns of adult movement, female calling, and mating followed a similar trend in the absence or presence of ultrasound. Female calling and mating, both in the absence and presence of ultrasound, primarily occurred during scotophase (21.00–07.00 hours). Ultrasound from the two devices significantly reduced the frequency of female calling and mating relative to unexposed moths. Consequently, the number of spermatophores transferred by males to females and egg production were lower in females exposed to ultrasound compared with unexposed females. In the absence of ultrasound, female P. interpunctella mated 2.9 times, resulting in 2.8 spermatophores/female. In the presence of ultrasound from the Cix 0600 device, a female mated 2.1 times and had 1.7 spermatophores. Corresponding values for the KSU device were 1.9 and 1.4, respectively. In the absence of ultrasound, 78% of the matings lasted 30–90 min, whereas in the presence of ultrasound 45–58% of the matings lasted either less than 30 min or more than 90 min. Moths exposed to ultrasound laid 96–130 eggs female^?1 compared with 229 eggs female^?1 for unexposed moths. Ultrasound did not affect the pre‐oviposition period and adult longevity of P. interpunctella.     

An intelligent system for estimating frog community calling activity and species richness

Over the past decade, dramatic declines in frog populations have been noticed worldwide. To examine this decline, monitoring frogs is becoming increasingly important. Compared to traditional field survey methods, recent advances in acoustic sensor technology have greatly extended spatial and temporal scales for monitoring animal populations. In this paper, we examine the problem of monitoring frog populations by analysing acoustic sensor data, where the population is reflected by community calling activity and species richness. Specifically, a novel acoustic event detection (AED) algorithm is first proposed to filter out those recordings without frog calls. Then, multi-label learning is used to classify each individual recording with six acoustic features: linear predictive coding coefficients, Mel-frequency cepstral coefficients, linear-frequency cepstral coefficients, acoustic complexity index, acoustic diversity index, and acoustic evenness index. Next, frog community calling activity and species richness are estimated by accumulating the results of AED and multi-label learning, respectively. Finally, ordinary least squares regression (OLS) is conducted to reveal the relationship between frog populations (frog calling activity and species richness) and weather variables (maximum temperature and rainfall). Experimental results demonstrate that our proposed intelligent system can significantly facilitate the effort to estimate frog community calling activity and species richness with comparable accuracies. The statistical results of OLS indicate that rainfall pattern has a lagged impact on frog community calling activity (significant in the first day after rainy day) and species richness (significant in the fourth day after rainy day). Temperature is shown to affect species richness but is less likely to change calling activity.     

A finite element evaluation of the moment arm hypothesis for altered vertebral shear failure force

The mechanism of vertebral shear failure is likely a bending moment generated about the pars interarticularis by facet contact, and the moment arm length (MAL) between the centroid of facet contact and the location of pars interarticularis failure has been hypothesised to be an influential modulator of shear failure force. To quantitatively evaluate this hypothesis, anterior shear of C3 over C4 was simulated in a finite element model of the porcine C3–C4 vertebral joint with each combination of five compressive force magnitudes (0–60% of estimated compressive failure force) and three postures (flexed, neutral and extended). Bilateral locations of peak stress within C3's pars interarticularis were identified along with the centroids of contact force on the inferior facets. These measurements were used to calculate the MAL of facet contact force. Changes in MAL were also related to shear failure forces measured from similar in vitro tests. Flexed and extended vertebral postures respectively increased and decreased the MAL by 6.6% and 4.8%. The MAL decreased by only 2.6% from the smallest to the largest compressive force. Furthermore, altered MAL explained 70% of the variance in measured shear failure force from comparable in vitro testing with larger MALs being associated with lower shear failure forces. Our results confirmed that the MAL is indeed a significant modulator of vertebral shear failure force. Considering spine flexion is necessary when assessing low-back shear injury potential because of the association between altered facet articulation and lower vertebral shear failure tolerance.     

Disruption of the odour-mediated mating behaviour of Plodia interpunctella using high-frequency sound

Abstract Indian meal moths, Plodia interpunctella Hübner (Lepidoptera: Pyralidae), have ears which are sensitive to high‐frequency calls produced by echolocating, insectivorous bats. The influence of artificially generated, high‐intensity, ultrasound signals (25 kHz, 106 dB SPL at 1 m distance) on different parameters involved in the odour‐mediated mating behaviour of this species and its potential use in population control was investigated. All moths flying towards olfactory cues in flight tunnel experiments reacted strongly to a 1 s ultrasound pulse by cessation of flight and falling out of the odour plume. The source contact proportion of both male moths orienting towards the female‐produced sex pheromone and of mated female moths orienting towards an oviposition cue was reduced by 40%, compared to unexposed moths. Calling females responded to the sound by retraction of the ovipositor or by falling to the ground. Long‐term exposure to repetitive pulses of ultrasound suppressed female calling by up to 27%. Furthermore, mating in plastic tents was disrupted by up to 58% in ultrasound‐treated tents using different sound regimens, compared to control tents. The results are discussed in relation to the potential use of ultrasound technology for the population control of pyralid stored product pests.     

Temporal distribution of PBAN‐like immunoreactivity in the hemolymph of Mamestra brassicae females in relation to sex pheromone production and calling behavior

A direct enzyme‐linked immunosorbent assay has been developed and applied to the analysis of PBAN immunoreactivity in female hemolymph of the cabbage armyworm, Mamestra brassicae. PBAN‐IR determinations have been carried out with third scotophase insects at different times of the photoperiod. The rhythm of calling and the pattern of pheromone production by third scotophase females at different times of the photoperiod have also been determined. PBAN‐IR and calling are well correlated. However, whereas pheromone titers decrease, both PBAN‐IR levels and percentage of calling females remain high in the last hours of the scotophase. These results are discussed in the context of the regulation of sex pheromone biosynthesis in M. brassicae. Arch. Insect Biochem. Physiol. 40:80–87, 1999. © 1999 Wiley‐Liss, Inc.     

Kinematic data on primate head and neck posture: Implications for the evolution of basicranial flexion and an evaluation of registration planes used in paleoanthropology

Kinematic data on primate head and neck posture were collected by filming 29 primate species during locomotion. These were used to test whether head and neck posture are significant influences on basicranial flexion and whether the Frankfurt plane can legitimately be employed in paleoanthropological studies. Three kinematic measurements were recorded as angles relative to the gravity vector, the inclination of the orbital plane, the inclination of the neck, and the inclination of the Frankfurt plane. A fourth kinematic measurement was calculated as the angle between the neck and the orbital plane (the head-neck angle [HNA]). The functional relationships of basicranial flexion were examined by calculating the correlations and partial correlations between HNA and craniometric measurements representing basicranial flexion, orbital kyphosis, and relative brain size (Ross and Ravosa [1993] Am. J. Phys. Anthropol. 91:305–324). Significant partial correlations were observed between relative brain size and basicranial flexion and between HNA and orbital kyphosis. This indicates that brain size, rather than head and neck posture, is the primary influence on flexion, while the degree of orbital kyphosis may act to reorient the visual field in response to variation in head and neck posture. Regarding registration planes, the Frankfurt plane was found to be horizontal in humans but inclined in all nonhuman primates. In contrast, nearly all primates (including humans) oriented their orbits such that they faced anteriorly and slightly inferiorly. These results suggest that for certain functional craniometric studies, the orbital plane may be a more suitable registration plane than Frankfurt “Horizontal.” Am J Phys Anthropol 108:205–222, 1999. © 1999 Wiley-Liss, Inc.