共查询到20条相似文献,搜索用时 15 毫秒
1.
《Biodemography and social biology》2013,59(3-4):239-252
Abstract Comparisons were made between members of Missouri Citizens for Life (MCL) and of the Abortion Rights Alliance (ARA) of Missouri. ARA members were more educated, urbanized, and had fewer children. MCL members were predominantly Catholic, and compared to ARA members, highly religious. ARA members were more inclined to favor equality of the sexes, especially in their approval of the ERA. ARA members were politically more liberal and more committed to free speech for social deviants. MCL members were much more committed to a conservative approach to matters of personal morality. MCL members regarded suicide and euthanasia as more objectionable than did their ARA counterparts, but they were also more militaristic. 相似文献
2.
《Ethology and sociobiology》1991,12(2):119-145
This study compared structural and contextual features of playful [rough-and tumble play (r/t)] and aggressive fighting based on direct playground observations of two classes of 8 and two classes of 11 year old children. Most bouts of r/t and aggressive fighting were dyadic, but significantly more bouts of the former involved three or more participants than the latter. Rough-and-tumble play was found to contain more individual action patterns than aggressive fighting, but the latter was more varied in form than some earlier studies had shown. Both wrestling and chasing were seen more in r/t than aggressive fighting, but restraint in bouts of chasing was not more common in playful chasing than aggressive chasing. Positive and neutral facial expressions were more characteristic of r/t, and negative facial expressions were more characteristic of aggressive fighting. Rough-and-tumble initiations were more likely to receive an r/t response and less likely to receive an aggressive response than were aggressive initiations. Participants in r/t were more likely to have been together than to have been apart prior to the encounter, but this tendency was strongly mediated by sex. In three out of the four classes, children were more likely to have been together prior to same sex r/t interactions and to have been apart prior to mixed sex r/t interactions. Participants in r/t were not significantly more likely to have been together beforehand than participants in aggressive fighting. Finally, while most bouts of r/t led to the participants remaining together, the proportion that did so was not significantly greater than was the case for bouts of aggressive fighting. Possible reasons why r/t and aggressive fighting did or did not differ in these ways are discussed. 相似文献
3.
The resistance of vegetative cells and of microcysts of Myxococcus xanthus to several destructive agents was compared. Fruiting-body microcysts were 300 times more resistant to 60 C, 5.4 times more resistant to ultraviolet light, and 19.3 times more resistant to sonic vibration than were vegetative cells. Whereas resistance to sonic vibration developed during the conversion of rods to refractile spheres, resistance to heat did not appear until after the conversion was complete. Both vegetative cells and microcysts of the yellow variant of this strain were more resistant to ultraviolet irradiation than was the tan variant. 相似文献
4.
The social grooming of captive female rhesus monkeys: Effects of the births of their infants 总被引:1,自引:0,他引:1
Frances L. Martel Claire M. Nevison F. David G. Rayment Michael J. A. Simpson 《International journal of primatology》1994,15(4):555-572
We observed the grooming interactions of 13 female rhesus monkeys (Macaca mulatta)before and for 12 weeks after the births of their infants. Mothers groomed for similar amounts of time before and after the
birth of their infants, but after the birth, the grooming they directed to their infants may have been at the expense of that
directed to other partners. Lactating females did not receive more grooming from other females but were approached more often,
suggesting that they were more attractive. Mothers that groomed their infants most groomed others least, as if grooming time
was limited for each mother or as if she was trying to compensate for avoiding interactions with other partners. Mothers of
male infants groomed others more than mothers with female infants did, which might be due to mothers with daughters receiving
more aggression and therefore avoiding interaction. Experienced and high-ranking mothers groomed their newborn infants considerably
more than primiparous mothers did in the 24 hr following birth. Grooming was preferentially directed at close kin before the
births of the infants. Mothers tended to groom higher-ranked partners more than they were groomed by them, and they tended
to receive more grooming from lower-ranked partners than they gave, as suggested in models of rank attractiveness. 相似文献
5.
David Zeigler 《Evolution》2012,5(4):585-588
One of the characteristics of science is its cumulative nature. As more discoveries are made and more is learned, we progressively come to a more and more complete understanding of the physical universe. Evolutionary biology serves as an excellent example of this progressive trend in knowledge, since we now understand significantly more about the mechanisms and details of the evolutionary process than we did in decades past. It is important to comprehend these progressive changes and communicate them effectively to students of evolutionary biology. 相似文献
6.
J M Tuladhar 《Journal of biosocial science》1985,17(2):185-193
This 1981 study is the 1st of its kind in Nepal. Analysis using a logit-linear model showed that contraceptive use in Nepal depends on many factors. Women aged 35-49 are 3 times more likely than women aged 15-24 to use contraceptives. Women with 4 or more children are 8 times more likely to use contraceptives than women with 1 or no children, and 2.5 times more likely than women with 2 or 3 children. The use of contraceptives is greatest among women whose offspring includes more sons than daughters, and least among women whose offspring are all daughters. Women who desire no more children are 5 to 6 times more likely to use contraceptives than women who desire more children. Women who have discussed desired family size with their husbands are more than 4 times more likely to use contraceptives than women lacking this type of communication. Women with some schooling are twice as likely to use contraceptives as women with no schooling. Contraceptive use is higher among women who do nonfarm work than farm work, and higher still among women who do not work. Urban women were almost twice as likely to use contraceptives as rural women. Women with less than 1 hour access to a family planning service outlet were 2 to 3 times more likely to use contraceptives than women whose access to these facilities was greater than 1 hour. The number of previous child losses per woman had no significant effect in contraceptive use. Conclusions are based on analysis of data from the Nepal Contraceptive Prevalence Survey, 1981. 相似文献
7.
The relationships of 42 rhesus monkey mother-infant dyads were examined to investigate the effects of the mothers' parity.
Primiparous mothers were found to be younger, more excitable and less confident than the multiparous mothers. They also received
more aggression from other adult females living in their social group and were more anxious about their infants, approaching
and leaving them more frequently. The primiparous mothers protected their daughters more than the multiparous mothers and
their daughters correspondingly spent more time in the ventro-ventral position and more time on the nipple. Their sons however
spent less time in contact with their mothers than did the sons of the multiparous mothers. Although the primiparous mothers
protected their daughters more than their sons, for the multiparous mothers the converse was true and sons received more maternal
protection. It is suggested that the greater protectiveness of the multiparous mothers towards male infants may be a consequence
of the interest siblings have in males, whereas the greater protectiveness of primiparous mothers to daughters may stem from
their greater vulnerability to attacks from adult females. The importance of mother-mediated sibling influences may explain
the lack of strong parity differences in previous studies. 相似文献
8.
Genkai-Kato M Yamamura N 《Proceedings. Biological sciences / The Royal Society》2000,267(1460):2397-2401
Theoretical and empirical evidence in a one-predator two-prey system consistently indicates a regular trend that the less profitable (therefore, less vulnerable) prey increases in abundance with enrichment. The response in the abundance of the more profitable (more vulnerable) prey to enrichment has, however, remained unclear. Previous theoretical models have assumed the less profitable prey as inedible, though its actual profitability is unknown. Here, relaxing this assumption, we show that the response of the more profitable prey abundance to enrichment depends critically on the profitability of the less profitable prey. Specifically, the more profitable prey increases in abundance with enrichment if the profitability of the less profitable prey is lower than a critical value so that it cannot support the predator population by itself even at high densities (in this case, the prey is referred to as 'unpalatable') and decreases otherwise. This establishes a more general rule which unifies the previous works and resolves the indeterminacy on the response of the more profitable prey. 相似文献
9.
Ruud van den Bos Tjard de Cock Buning 《Ethology : formerly Zeitschrift fur Tierpsychologie》1994,98(1):14-37
The behaviour of a group of female domestic cats (n = 10) under laboratory conditions is described. Behavioural observations were made on a total of 20 days during a 3-month period; only frequencies were recorded. Analysis of the winner/loser matrix revealed a linear rank order. This rank order correlated with several variables. The higher the rank, the more offensive threats a cat emitted overall, and the more defensive threats it received overall; within a pair, the higher-ranking cat displayed more offensive threats, whereas the lower-ranking cat displayed more defensive threats. The higher a rank, the more bouts of social licking a cat emitted overall, and the more bouts of social sniffing and social rubbing it received overall; within a pair, the higher-ranking cat tended to show more social licking, whereas the lower-ranking cat showed more social sniffing. The higher the rank, the more time a cat tended to spend on the floor, and the less time it spent in a 16-compartment complex; the further animals were apart in rank, the smaller were the proximity scores between them. Finally, higher-ranking cats tended to gain weight, whereas lower-ranking cats tended to lose weight. These data suggest that the concept of dominance may be applied to this group of cats. It is discussed whether the observed rank order is specific for indoor conditions under which the cats were living. The role of social licking is also discussed. 相似文献
10.
Reimut Wette 《Bulletin of mathematical biology》1953,15(3):251-260
A critical examination of the “classical” theories of photoreception in view of more recent experimental findings yields the
result that these theories do not possess the property to describe all the more significant phenomena of photoreception correctly,
and to some extent suffer the lack of more general applicability. The basis for a new and presumably more general theory of
photoreception based on dynamical aspects is laid out. Emphasis is put on the time course of afferent and efferent excitation
in the photoreception model, consisting of a receptor element, an afferent and an efferent neuron of the one-factor Rashevsky-type,
and an effector organ. 相似文献
11.
The use of psychiatric services by patients with a suicidal history was examined to see if they placed a greater long-term burden on these services than other types of patient. Suicidal patients spent significantly more days in hospital and made more outpatient attendances; suicide attemptors in particular not only needed more emergency consultations but also spent more days in hospital. A more economical yet more effective treatment policy for the suicidal patient is needed. 相似文献
12.
恢复措施对退化草地羊草种群有性生殖数量特征的影响 总被引:8,自引:2,他引:8
在封育和翻耙处理的退化羊草草地上,对羊草种群有性生殖的数量特征进行了比较研究.结果表明,翻耙样地羊草种群密度下降显著,生殖蘖密度变化不显著,生殖蘖穗长、节间长、生殖生长比率、穗节数、小穗数、小花数、饱满籽实数和结实率都有显著增长,籽实产量、净籽实重和千粒重分别是封育样地的2.68、3.49和1.3倍.在翻耙样地中,羊草种群发育有复小穗的生殖蘖比封育样地多16%,生殖蘖上复小穗的数量也显著增加,生殖蘖以相对少的小穗,生产了较多的小花和更多的籽实来提高种群的籽实产量.两个样地中羊草种群的生物量生殖分配在种群对生殖蘖RA1、生殖蘖对穗序RA4、穗序对籽实RA6 3个层次上无显著差异,而种群对穗序RA2、生殖蘖对籽实RA5的生殖分配差异显著,种群对籽实RA3的生殖分配差异极显著. 相似文献
13.
The enzyme from leaves of cold-hardened rye plants was: (1) more stable between pH 7.75 and 8.3 (2) more stable at ?25°C (3) less sensitive to SDS and (4) more sensitive to urea than the same enzyme from unhardened plants. The molecular weights of the purified enzymes from the two sources were the same but their charges differed. 相似文献
14.
Mario A. Fares Orla M. Keane Christina Toft Lorenzo Carretero-Paulet Gary W. Jones 《PLoS genetics》2013,9(1)
Researchers have long been enthralled with the idea that gene duplication can generate novel functions, crediting this process with great evolutionary importance. Empirical data shows that whole-genome duplications (WGDs) are more likely to be retained than small-scale duplications (SSDs), though their relative contribution to the functional fate of duplicates remains unexplored. Using the map of genetic interactions and the re-sequencing of 27 Saccharomyces cerevisiae genomes evolving for 2,200 generations we show that SSD-duplicates lead to neo-functionalization while WGD-duplicates partition ancestral functions. This conclusion is supported by: (a) SSD-duplicates establish more genetic interactions than singletons and WGD-duplicates; (b) SSD-duplicates copies share more interaction-partners than WGD-duplicates copies; (c) WGD-duplicates interaction partners are more functionally related than SSD-duplicates partners; (d) SSD-duplicates gene copies are more functionally divergent from one another, while keeping more overlapping functions, and diverge in their sub-cellular locations more than WGD-duplicates copies; and (e) SSD-duplicates complement their functions to a greater extent than WGD–duplicates. We propose a novel model that uncovers the complexity of evolution after gene duplication. 相似文献
15.
Do different cultures hold different views of intentionality? In four studies, participants read scenarios in which the actor’s distal intent (a focus on a broader goal) and proximal intent (a focus on the mechanics of the act) were manipulated. In Studies 1–2, when distal intent was more prominent in the actor’s mind, North Americans rated the actor more responsible than did Chinese and South Asian participants. When proximal intent was more prominent, Chinese and South Asian participants, if anything, rated the actor more responsible. In Studies 3–4, when distal intent was more prominent, male Americans rated the actor more responsible than did female Americans. When proximal intent was more prominent, females rated the actor more responsible. The authors discuss these findings in relation to the literatures on moral reasoning and cultural psychology. 相似文献
16.
《Anthrozo?s》2013,26(1):26-42
AbstractWe examined the attitudes, perceptions and behaviors of both pet-abusing and non-pet-abusing perpetrators of family violence. Using data collected from victims residing at domestic violence shelters, results indicated that relative to their non-pet-abusing counterparts, pet-abusing batterers tend to less often show affection toward their pets, more often communicate with their pets only through commands and threats, more often view companion animals as property, are more likely to scapegoat their pets, and are more likely to have unrealistic expectations about their pets, more frequently punish their pets, and are more sensitive to stressful life events—particularly those perceived to be caused by the pet. We also queried respondents about batterers' past history with pets, the frequency and type of abuse inflicted on animals, the number of batterers who hunt, the frequency with which children witnessed abuse of the family pet, the impact of animal guardianship on decisions to remain with or return to the batterer, and where companion animals ended up when victims fled the batterer. 相似文献
17.
18.
不同基因型小麦花药培养过程中药壁变化的研究 总被引:3,自引:0,他引:3
在相同的培养条件下 ,比较了不同基因型小麦花药培养过程中药壁变化的差异。组织切片观察表明 :易诱导材料花药培养过程中 ,药壁细胞发育充实 ,活力强 ,降解衰退较难诱导材料有所延缓 ;两种材料的花药刚离体时绒毡层就存在着明显的差异 相似文献
19.
Differences in the base composition of genomes can occur because of GC pressure, purine-loading pressure (AG pressure) and RNY pressure, for which there are possible functional explanations, and because of the more abstract pressures exerted by individual bases. The graphical approach of Muto and Osawa was used to analyse how bacteriophages and bacteria balance potentially conflicting pressures on their genomes. Phages generally respond to AG pressure by increasing A while keeping T constant, and by decreasing C while keeping G constant. In contrast, bacteria generally increase both A and T, the former more so, and decrease both G and C, the latter more so. These differences largely occur at third codon positions, which are more responsive than first and second codon positions to AG pressure and GC pressure. Phages respond to AG pressure more in the third codon position than bacteria, whereas bacteria respond more in the first codon position than phages. Conversely, bacteria respond to GC pressure more in the third codon position than phages, whereas phages respond more in the first codon position than bacteria. As GC pressure increases, A is traded for C and AG pressure decreases; first and second codon positions, having more A than T, are most responsive to this negative effect of increased GC pressure; third positions either do not respond (phages) or respond weakly (bacteria). In a set of 48 phage-host pairs, degrees of purine loading were less correlated between phage and host than were GC percentages. These results suggest that pressures on conventional and genome phenotypes operate differentially in phages and bacteria, generating both general differences in base composition and specific differences characteristic of particular phage-host pairs. The reciprocal relationship between GC pressure and AG pressure implies that effects attributed to GC pressure may actually be due to AG pressure, and vice versa. 相似文献
20.
三种笼养灵长类活动时间分配的比较研究 总被引:2,自引:1,他引:1
采用焦点动物法和连续记录法对3种笼养灵长类活动时间分配进行比较研究。结果表明,川金丝猴Rhi-nopithecus roxellanae和熊猴Macaca assamensis用于休息的时间多于猕猴Macaca mulatta,移动时间则相反;川金丝猴和猕猴用于理毛的时间多于熊猴。不同性别年龄组之间的活动时间分配有差异,主要表现在川金丝猴母亲用于理毛的时间明显多于成年儿子,用于玩耍的时间则相反;猕猴成年雄性的移动时间和理毛时间多于成年雌性,玩耍时间则少于成年雌性;熊猴成年雌性的移动时间多于成年雄性,与成年个体相比,幼体花更多的时间用于玩耍,而相应的减少了其休息时间。 相似文献