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111.
Modifications in a zoo exhibit were made to increase the arboreality of an aged female diana monkey, and to increase her use of the central portion of the exhibit where a new food shelf had been added. Branches, which formed ramps to this shelf, also were added. Following these changes, the aged female's arboreality increased slightly, and her use of the central portion of the exhibit increased significantly. Changes in habitat use following these modifications also were noted in the other two diana monkeys in the group. These results suggest that zoo habitats can be made more usable for individuals whose behavioral capabilities might be limited due to age or physical disability. 相似文献
112.
Newly emerged Atlantic salmon (Salmo salar) were observed from May to August 1981 at six isolated redds in Washington County, Maine, USA. Territorial size and distribution were measured. At the end of the emergence period (12 to 28 May), fish maintained positions (stations) at redds where water velocity did not exceed 52 cm s–1 By 12 June, most salmon (80–96%) had moved off the redds of origin and had established territories 1 to 5 m from the redd. The area defended increased substantially after mid-June, but territorial aggression diminished by 15 July, and the fry dispersed downstream. All fish observed were territorial, and the percentage of time during which stations were held decreased from 89 in mid-May to as low as 40% in mid-June.Cooperators are the Maine Department of Inland Fisheries and Wildlife, University of Maine, U.S. Fish and Wildlife Service, and the Wildlife Management Institute 相似文献
113.
C. Planchon J. Fesquet 《TAG. Theoretical and applied genetics. Theoretische und angewandte Genetik》1982,61(4):359-365
Summary Photosynthesis and transpiration in wheats and in their progenitors were analyzed in relation to their genome, ploidy and selection. The values of these parameters markedly depend on a specific effect of the D genome and on leaf enlargement in the course of evolution in wheats. Leaf enlargement has had a marked effect on photosynthesis in the genotypes that are devoid of the D genome; in addition, their photosynthetic capacity is greater in forms with lower leaf area. The increase in the mesophyll resistance rm to CO2 transfer is in relation to the increase in leaf area and is mainly responsible for the decrease in photosynthesis rate.Owing to its stomatal regulation, Triticum aestivum L. is characterized by good water use efficiency in spite of its large leaves and of its low net photosynthesis. On the basis of the photosynthesis rate, the large leaf factor does not appear to be a good selection criterion for the Triticum durum genotypes that are devoid of the D genome. 相似文献
114.
JOSEPH HELLER MICHAL VOLOKITA 《Biological journal of the Linnean Society. Linnean Society of London》1981,16(4):279-284
Along the coastal plain of Israel, shell darkness of the polymorphic land snail Xeropicta vestalis is positively related to the extent of perennial vegetation. It is not related to rain, temperature, geographic position or darkness of the ground.
White shells reflect more radiation than dark ones do, and therefore in Israel's coastal plain, where solar radiation is very strong, they are favoured. Perennial vegetation, where it occurs, shields the snails from the sun by absorbing radiation, so that snails amongst them can afford to be darker, and thus more cryptic. Hence, the more perennial vegetation in the habitat, the darker the shells.
Also during the Pleistocene, when temperatures were 5–10°C lower than today, the shells of the coastal plain were as pale as recent ones are. The distribution of a snail-predator, Gerbillus allenbyi , which is restricted to sandy biotopes where perennial bushes occur, and which was absent from Israel during the Pleistocene, could perhaps explain the distribution of X. vestalis morphs, both today and in the past. 相似文献
White shells reflect more radiation than dark ones do, and therefore in Israel's coastal plain, where solar radiation is very strong, they are favoured. Perennial vegetation, where it occurs, shields the snails from the sun by absorbing radiation, so that snails amongst them can afford to be darker, and thus more cryptic. Hence, the more perennial vegetation in the habitat, the darker the shells.
Also during the Pleistocene, when temperatures were 5–10°C lower than today, the shells of the coastal plain were as pale as recent ones are. The distribution of a snail-predator, Gerbillus allenbyi , which is restricted to sandy biotopes where perennial bushes occur, and which was absent from Israel during the Pleistocene, could perhaps explain the distribution of X. vestalis morphs, both today and in the past. 相似文献
115.
Summary Differences in the productivity of establishedP. radiata plantations on pasture and forest soils were found to be reproducible withP. radiata seedlings in a glasshouse environment. The growth of seedlings on pasture soil exceeded that of seedlings on native forest
soil (the ‘primary pasture effect’). After a history of pine on both native and pasture soils a residual effect of pasture
on seedling growth was evident (the ‘secondary pasture effect’). However, the effect of a history of pine plantation (the
‘pine effect’) was to decrease the productivity of both native and pasture soil as assessed by seedling growth. These effects
were not related to changes due to land management in mycorrhizal infection or in soil structure. The analysis of seedling
growth leads to the conclusion that soil fertility, particularly the availability of nitrogen and phosphorus, has changed. 相似文献
116.
Summary The influence of continuous cropping and soil test based fertilizer use on the organic nitrogen fractions in the plough layer
has been studied in a Typic Ustochrept soil. Seven years of multiple cropping without manuring caused marked depletion in
all the hydrolysable fractions except unidentified hydrolysable N namely, hexosamine (48.8%), hydrolysable ammonium (23.9%)
and amino acid (7.3%) as compared to an adjacent fallow. Fertilizer nitrogen application maintained the levels of various
forms of N as in the fallow plots and nitrogen in conjunction with phosphorus raised the status of amino acid N. Phosphate
improved the contents of hydrolyzable ammonium and total hydrolyzable N whereas farmyard manure enhanced the latter only.
The system of intensive cropping followed with appreciably high doses of fertilizers favoured greater immobilization of N
in hydrolyzable ammonium and total hydrolyzable fractions.
Original not seen 相似文献
117.
LYNNE R. PARENTI 《Biological journal of the Linnean Society. Linnean Society of London》1980,13(3):225-242
Phylogenetic systematics (cladistics) is a theory of phylogeny reconstruction and classification widely used in zoology. Taxa are grouped hierarchically by the sharing of derived (advanced) characters. The information is expressed in a cladogram, a best estimate of a phylogeny. Plant systematists generally use a phenetic system, grouping taxa on overall similarity which results in many groups being formed, at least in part, on the basis of shared primitive characters.
The methods of phylogenetic systematics are used to create a preliminary cladogram of land plants. The current classification of land plants is criticized for its inclusion of many groups which are not monophyletic.
Objections to the use of phylogenetic systematics in botany, apparent convergences within major groups and frequent hybridization, are shown to be invalid. It is concluded that cladistic analysis presents the best estimate of die natural hierarchy of organisms, and should be adopted by plant systematists in their assessment of plant interrelationships. 相似文献
The methods of phylogenetic systematics are used to create a preliminary cladogram of land plants. The current classification of land plants is criticized for its inclusion of many groups which are not monophyletic.
Objections to the use of phylogenetic systematics in botany, apparent convergences within major groups and frequent hybridization, are shown to be invalid. It is concluded that cladistic analysis presents the best estimate of die natural hierarchy of organisms, and should be adopted by plant systematists in their assessment of plant interrelationships. 相似文献
118.
Takashi Torigoe 《Primates; journal of primatology》1985,26(2):182-194
Seventy-four primates species (24 genera of six families) were presented with a nylon rope and a wooden cube, and their subsequent
manipulations were recorded in detail. Five hundreds and six manipulation patterns were distinguished on the basis of the
actions performed, body-parts used and relations to other objects. Inter-specific comparisons revealed three groups: (1) lemurs,
marmosets, spider monkeys and leaf-eaters; (2) Old World monkeys except leaf-eaters; and (3) cebus monkeys and apes. The first
group had the smallest repertoire of manipulations, in which only a few types of actions and body-parts were involved. The
second and third groups had more varied modes of manipulation. Actions such as Roll, Rub and Slide, and use of fingers characterized
these groups. Except for the lesser ape, their manipulations were frequently related with other objects. Moreover, actions
such as Drape, Drop, Strike, Swing and Throw were typical of the third group. The factors producing such inter-specific differences
in manipulations and the relations to tool use are discussed. 相似文献
119.
120.
《Saudi Journal of Biological Sciences》2022,29(6):103307
Malathion (MAL) is an organophosphate insecticide that disrupts the body's antioxidant system; it is one of the earliest organophosphate insecticides extensively used as dust, emulsion, and vapor control a wide variety of insect pests under different conditions. This experimentation aims to evaluate the influence of Arabica coffee oil and olive oil on MAL-induced nephrotoxicity in male rat. 6 sets bearing the same number of animals were applied to this experiment. Each set comprised 10 rats. The first set of rats was used as the control group; rats in the second set were exposed to MAL measured at 100 mg/kg body weight for 7 weeks. Animals in the third and fourth set were treated with 400 mg/kg body weight of Arabica coffee oil and olive oil, and 100 mg/kg body weight of MAL. The fifth, together with the sixth set, were fed with a similar proportion of Arabica coffee oil and olive oil as administered to the third set of rats. After the experimental duration, rats of group 2 showed severe biochemical alterations, including significant increases of creatinine, uric acids, and urea nitrogen (BUN), resulting in marked decreases in serum albumin values and total protein (TP). Severe histopathological and immunohistochemical alterations of kidney tissues were observed in exposed MAL-intoxicated rats. Administration of these oils reduced the detected biochemical, histopathological modifications caused by MAL intoxication. Two active ingredients in Arabica coffee oil (oleic acid) and olive oil (hydroxytyrosol) showed good cyclooxygenase-2 (COX 2) interaction. Moreover, oleic acid from coffee oil and olive oil exhibited impressive association with xanthine oxidase (XO). The current finding showed that coffee oil and olive oil could be appraised as possible and a likely deterrence component against nephrotoxicity brought about by MAL. 相似文献