Anti-predation does not fully explain grouping in the Chinese water deer (Hydropotes Inermis)

The grouping behavior of the Chinese water deer (Hydropotes inermis) was studied at Poyang Lake National Nature Reserve, Jiangxi, China. I made three predictions to test the hypothesis that grouping is an anti-predatory strategy: (1) group size is negatively related to vegetation cover, (2) animals in groups have more time to feed than solitary animals, and (3) animals spend less time in vigilance when they are in groups than when they are alone. Results showed that group size was largest in the mating season and smallest in the parturition season. Deer tended to form larger groups when they were in short grass areas than in tall grass areas. Hence, the first prediction is supported. However, solitary deer and deer in groups did not differ in time allocated to feeding or vigilance. Therefore, predictions 2 and 3 are not supported. Time budget analysis revealed that females with young allocated less time to feeding, but more time to walking during the non-mating season. During the mating season, females grouped with males spent less time feeding than solitary females, and solitary males spent more time looking for females than did males grouped with females during the mating season. In light of the complications found in the grouping behavior of the water deer, the anti-predatory hypothesis seems to be insufficient as the only reason for the deer to group. Other socio-ecological factors are also important in determining the grouping behavior of this species

Blood is not always thicker than water: The limited effect of kin selection on human kinship in the traditional Chinese family

To examine the importance of kin selection in shaping human societies, this study analyzed the kinship system practiced in traditional China for two millennia and teased apart its underlying genetic and other, presumably cultural, components. The results demonstrate that, in the traditional patrilineal Chinese family, both genetic relatedness and the cultural factor of generation were important in determining kinship status for male agnates (genetically related relatives). For female agnates, however, only genetic relatedness was important. Another surprising finding was that the influence of gender was not as important as genetic relatedness. The most interesting finding in this study, however, was that kin selection and culture (i.e., seniority in generation and age) played vastly different roles in different lineages in the Chinese family: for collateral (indirect) agnates, genetic relatedness was the most important factor in determining their kinship status, but for lineal (direct) agnates, its importance was overridden by seniority in generation and age, a cultural factor. Several other bio-cultural factors also explained a considerable amount of variance in kinship status. Since kinship profoundly affected, and was often the foundation of, the legal and social systems in dynastic China, kin selection, while its strength may differ remarkably between lineal and collateral relatives, could act as a selective force in Chinese families

Passing Pains: Revenge, Retaliation, and Redirected Aggression in a New Light

A review of David P. Barash and Judith Eve Lipton, Payback: Why We Retaliate, Redirect Aggression, and Take Revenge, Oxford University Press: New York, 2011, 209 pp., US$24.95, ISBN 019539514X (hardcover)

Use of anal gland secretion to distinguish the two beaver species Castor canadensis and C. fiber

Introduced North American beavers Castor canadensis pose a potential threat to the continuing recovery of Eurasian beaver C. fiber populations in several European countries. For management purposes, it is necessary to be able to identify and distinguish the two species. This, however, is difficult because the two species are morphologically, ecologically and behaviorally similar. To find a method for species identification, we examined the possibility of using anal gland secretion (AGS) collected from the two beaver species. We asked 20 inexperienced volunteers to inspect the color and viscosity of the AGS. When we provided the volunteers with the sex of each beaver and descriptions of the color and viscosity of AGS from males and females of the two species, all volunteers could 100% correctly identify the two species. We therefore conclude that the color and viscosity of the AGS can be used for a quick and easy identification of the two beaver species

Mechanical Properties of Carbon Nanotubes-Polymer Composites

Carbon nanotubes (CNTs), as a one-dimensional material, have outstanding mechanical properties such as extreme tensile strength and Young’s modulus. At present, to prepare pure CNTs materials is quite difficult and the mechanical properties of the materials are limited in a low level. Because of their extraordinary mechanical properties and high aspect ratio, CNTs are considered to be ideal candidates for polymer reinforcement. In addition, CNTs/polymer composite materials are much easier to prepare than pure CNTs materials, so they have been paid much attention by researchers recently. However, challenges must be faced to prepare the CNTs/polymer composite with ultimate mechanical properties. So in this chapter, the main concerns are how to disperse CNTs in polymer matrix to prepare homogenous composite dispersions, how to prepare homogenous CNTs/polymer composite using possible fabricating processes based on the homogenous dispersions, how to increase the fiber mechanical properties especially through the enhancing interaction between polymer and CNTs, controlling the amount of CNTs and enhancing their orientation in the matrix

Heritability of kinship pheromone in the beaver: How is information about relatedness coded?

We attempted to estimate the narrow-sense heritability of single compounds and whole profile of the anal gland secretion (AGS) with the regression method using several sets of relatives in the beaver (Castor canadensis). We used GC (gas chromatography) and GC-MS (mass spectrometry) to characterize and quantify chemical compounds in beaver AGS. We found that the heritability of single compounds seemed to be low, whereas the heritability of AGS profile appeared to be moderate. We conclude that many compounds might be involved in the coding of genetic relatedness, which was through a combination of analog and digital coding using many compounds

Influence of male surgical sterilization on the copulatory behavior and reproduction of Brandt\u27s vole

The influence of sterilized male on the copulatory behavior and reproduction of Brandt′s vole was studied by using the method of surgical sterilization. Male surgical sterilization did not influence the copulatory behavior of Brandt\u27s vole. Mating times with intact mates and litter size of female Brandt′s voles in male sterilized groups decreased compared with the control groups. The results supported the hypothesis of competitively reproductive interference of sterilized males. Thus, sterilization can be a viable method to control voles

Influence of increasing number of mating partners on mating behaviour and reproduction in Brandt’s voles

The influence of increasing number of mating partners on the copulatory behavior and reproduction in Brandt’s voles (Microtus brandti) was studied. Compared with the control group of 1 ♂ + 1 ♀, our results showed when increasing only female partners, the mating opportunity was increased in males while decreased in female in the treatment group of 1 ♂ + 2 ♀♀; the mating opportunity of male and female were both decreased significantly in the treatment group of 1 ♂ + 3 ♀♀. When increasing only male partners, male mating opportunity in treatment groups 2 ♂♂ + 1 ♀ and 3 ♂♂+ 1 ♀ decreased significantly while no change was significant in females in both treatment groups. When increasing the number of male and female partners simultaneously in the treatment group of 2 ♂♂ + 2 ♀♀, the mating opportunity for both males and females was decreased significantly. Comparing with the control, the mean litter size in all five-treatment groups lessened significantly and female pregnancy rate dropped significantly if they copulated less than five times. From these results, we have demonstrated a significant reproductive interference due to mate competition in Brandt’s voles and thus, competitively reproductive interference may be an important behavioral mechanism in regulating population density in this rodent species. However, due to possible laboratory artifacts, we still need further study, especially in the field, to validate our results

The effect of male competition on female choice in Brandt’s vole, Lasiopodomys brandti

The effect of male competition on female choice in the Brandt’s vole (Lasiopodomys brandti) was studied in the laboratory. Using a two-way choice test, we showed that when males did not compete, estrous females preferred and mated with the dominant males, but non-estrous females preferred subordinate males. However, when males competed, all dominant males gained the priority to mate, and the amicable behaviour between males, regardless of their dominant status, and between non-estrous females increased, compared with the behaviour between males and the estrous females. These results showed that interactions among Brandt’s voles were not only influenced by male competition but also by reproductive status of female voles

The Behavioral Ecology of the Tibetan Macaque

This open access book summarizes the multi-disciplinary results of one of China’s main primatological research projects on the endemic Tibetan macaque (Macaca thibetana), which had continued for over 30 years, but which had never been reported on systematically. Dedicated to this exceptional Old World monkey, this book makes the work of Chinese primatologists on the social behavior, cooperation, culture, cognition, group dynamics, and emerging technologies in primate research accessible to the international scientific community