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61.
Koichi Negayama Takako Negayama Kiyomi Kondo 《International journal of primatology》1986,7(4):365-378
Parturitional behavior in 12 caged Macaca fuscatawas analyzed. Wild-caught mothers showed adequate maternal behaviors immediately following the neonate’s expulsion. Parity
differences existed in the behaviors; primiparae were more idiosyncratic than were multiparae. Among multiparae, those with
two or more offspring were uniformly adequate, but those with a single birth experience varied in the adequacy of the maternal
care they provided at parturition. Mothers embraced and licked their neonates and had ventroventral contact with them frequently
immediately after parturition but decreased these behaviors after expulsion of the placenta. In contrast, mothers showed allogrooming
after consuming the placenta. Placentophagy was correlated with the level of orality represented by maternal licking behaviors.
An isolation-reared primipara reacted to her newborn in a basically negative manner, although she showed little actual aggression.
She showed a rapid shift in her negative behavior during the immediate postpartum period. This mother’s newborn sought contact
with her, indicating the neonate’s active role in establishing a stable mother-neonate bond. 相似文献
62.
William J. Matthews Mary E. Power Arthur J. Stewart 《Environmental Biology of Fishes》1986,17(4):291-297
Synopsis
Campostoma spp., widespread and abundant herbivorous minnows of eastern North America, produce distinctive grazing scars when feeding on algae attached to natural substrates in streams. These scars are particularly prominent upon the low growth forms of blue-green algae that dominate the attached algal flora of many upland streams. In one stream pool in the Ozark uplands of Oklahoma, numbers and sizes of grazing scars coincided with numbers and sizes of individual Campostoma that occurred across a depth gradient, demonstrating that the information contained in the scars can provide quantification of microhabitat use and grazing intensity of these important herbivores. The results also support the hypothesis that in environments free of aquatic predators, larger fish use deeper parts of available stream habitats, particularly if threats from terrestrial or avian predators exist. 相似文献
63.
Recently we noted the effects of experimental diets on microscopic dental wear in the American opossum and concluded that it might prove difficult to distinguish the microwear produced by an insectivorous diet from that produced by some kinds of herbivorous ones. We also noted that wear caused by gritty diets and those containing plant opal, although they might be confused with one another, are easily distinguished from other sorts of dietary wear. Our conclusions have been challenged on the basis that possibly we did not allow sufficient time in the experiments for diagnostic wear patterns to emerge. Additional data reported here show that this is not so. Even in our n “control” animals, fed a relatively soft unabrasive diet, enough time elapsed to produce significant dental wear. A new technique is described which for the first time allows the study of changing patterns of microscopic wear in a living animal over a period of time, thus allowing each animal to serve as its own control. A solution containing a broad-spectrum proteolytic enzyme when applied to the teeth of an anesthetized animal removes the proteinaceous coat (pellicle) which will otherwise obscure wear scratches. Precision dental impressions can then be made which reveal the details of the pattern of microwear on the teeth. 相似文献
64.
We quantified microscale pattern in vegetation and seed assemblages along a 24 m transect before and for two years following a controlled burn in chamise (Adenostoma fasciculatum) chaparral in central coastal California. Our objective was to document scale-dependent correlation between pre-burn seed assemblages, pre-burn canopy cover, microtopography, soil temperatures during burning, post-burn seed assemblages and post-burn vegetation. Scale-dependent correlations among pre- and post-burn seed densities, maximum soil temperatures during burning, microtopography and post-burn vegetation were measured based on two-term local covariance analysis.Seed distribution varied among species prior to fire, with seeds of some annual species concentrated in gap areas. Maximum soil temperatures during burning ranged from less than 50 °C to 225 °C, and were generally lowest in gaps in the pre-burn canopy. These gaps were associated with local topographic depressions. After burning, readily germinable seeds were concentrated in or near gaps in the pre-burn canopy. Germination of different species was variously enhanced, diminished or unchanged by the passage of fire. Post-burn vegetation was very patchy, with some areas nearly devoid of seedlings and other areas, especially pre-burn canopy gaps, supporting numerous seedlings. Seedling recruitment patterns in the second year were generally highly correlated with patterns in pre-burn seed banks and first year vegetation. Although many species exhibited similar recruitment patterns, several different mechanisms may have been responsible for the origin of those patterns. 相似文献
65.
黑卷尾繁殖期领域性的初步研究 总被引:2,自引:0,他引:2
鸟类的领域性是鸟类行为生态学研究的一个重要内容。在这方面国外进展很快,但国内工作较少,专文报道除三宝鸟之外,其它颇为罕见。1987年夏季,我们在太原市南郊对该地区的夏候鸟黑卷尾(Dicrurus macrocercus)的领域行为进行了观测。现将资料整理分析如下。一、工作区与工作方法太原盆地的自然环境和鸟类群落状况已有报道,在此不再赘述。工作区选在小马—加节两村之间约190ha的区域内(图1)。其 相似文献
66.
67.
Yaushisa Henmi 《Ecological Research》1989,4(3):261-269
Mortality of eggs during incubation was estimated for three ocypodid crabs,Scopimera globosa, Ilyoplax pusillus andMacrophthalmus japonicus, and the influence of incubation sites was discussed. These crabs all lived in isolated burrows and fed on sediments during
day time low tide.S. globosa andI. pusillus inhabited the upper intertidal sandflats, whereasM. japonicus inhabited the lower intertidal mudflats. Females of bothS. globosa andI. pusillus remained in their plugged burrows without feeding throughout incubation and the mortality of eggs was low despite large broods
relative to body size. On the other hand, females ofM. japonicus fed actively on surface mud during incubation and the mortality of eggs was high despiite small broods relative to body size.
InS. globosa andI. pusillus, the ovaries of ovigerous females were small until egg-hatching, whereas inM. japonicus, the ovaries grew rapidly during incubation and females were able to produce consecutive broods. I conclude that incubation
of eggs in burrows may be advantageous in species which inhabit the upper interidal sandflats, even though the crabs cannot
forage during incubation, since otherwise their eggs would be exposed to strong heat stress and desication during the summer.
Furthermore, such species may produce few large broods because of less frequent interruption of feeding than that associated
with production of many small broods. 相似文献
68.
Phillip S. Lobel 《Environmental Biology of Fishes》1989,25(1-3):125-130
Synopsis Spawning by the banded butterflyfish,Chaetodon multicinctus (Chaetodontidae) was observed on coral reefs off Kona, Hawaii. These fish occurred in male-female pairs during normal daytime
activities, a behavior which is typical for the family. Courtship is also a paired male-female activity. During spawning,
however, other individuals (males?) may intrude on the spawning pair. Spawning typically takes place at least a meter or two
above the bottom. The spawning position consists of the male below and behind the female with his snout against the female's
ventral flank or anal fin area. Intruding individuals may join in when the pair is in position and about to spawn. Intruders
line-up against the male in the same position as he is against his female. Underwater photographs are included to illustrate
these behaviors. 相似文献
69.
Nine accessions ofVicia narbonensis, considered to be the wild progenitor of faba bean (Vicia faba), were investigated to ascertain the nature and extent of intraspecific karyotypic polymorphism. The chromosome complements resolved into four distinct types (A, B, C, D), and the meiotic data of F1 hybrids (A × B, B × C, A × C) revealed that alteration in chromosome morphology is the result of segmental interchanges. The interchange complexes indicate that the parents differ from each other by 1 to 2 interchanges. It is also evident that karyotype B, and not A as previously reported, is the normal karyotype of the species, and A and C are single homozygotes for unequal interchange. The comparative karyomorphology of the parents and the hybrids, and of two interchange heterozygotes of four chromosomes each in F1 hybrids of A × C shows that the chromosomes involved in the single interchange homozygotes (A, C) are not common and the breaks in both interchanges occurred in short and long arms of the involved chromosomes. Identification of the interchanged chromosomes in the complements and the frequency of ring and chain quadrivalents in the heterozygotes enabled location of the breakpoints. The present results provide probably the first example indicating that interchange homozygosity (A) is not only firmly established but also has enabled the species to spread further by adapting to a wide range of habitats. — The genetic relationships between A and D are very different. All seven chromosome pairs in D could be distinguished from A, and for that matter, B and C as well. From the meiotic pairing properties it is also amply clear that genome D is well differentiated from A and possibly B, and C, and deserves special status. 相似文献
70.
Copulatory behavior unrelated to conception is sometimes observed in some non-human primates including the Japanese monkey.
In the present study, the authors examined whether a mature follicle or a newly formed fresh corpus luteum was observed in
the ovaries of female Japanese monkeys which displayed the copulatory behavior unrelated to conception.
Post-conception copulatory behaviors were observed in three out of four females usually kept in individual cages in an air-conditioned
room, and in two out of three females without infants kept in an outdoor group cage. However, neither a mature Graafian follicle
nor a fresh corpus luteum formed newly after conception was observed in any of these females by laparoscopic examinations
conducted immediately after termination of the copulatory behavior. In females with infants born in the preceding birth season,
copulatory behaviors were observed in three out of four females kept in the outdoor group cage, and in two out of four females
in a free-ranging troop. Ovulation was confirmed in one case out of the three kept in the outdoor group cage, but neither
a mature follicle nor a newly formed corpus luteum was observed in the remaining four females.
These findings suggest that copulatory behavior in the Japanese monkey is not always controlled by the development of a follicle
or ovulation in the ovary. 相似文献