1994 Vol. 15, No. 2

Display Method:
研究论文
Based on the data obtained by monthly samplings from Fuxian Lake in the duration of one year (Nov.1988 to Nov.1989),the author has investigated into the biological characters of fishes of Fuxian Lake.From the viewpoint that organisms evolve along with their environments,the adaptative significance of these characters are further explained with reference to the geological history of Fuxian Lake.It is found that a series of common characters are shared by all or many species of fishes.These common characters can be further recognized as original or derived ones according to the principle of character analysis.The original characters suggest that the extant fishes of Fuxian Lake be originated from the ichthyofauna of rivers connected to the lake.The derived characters are supposed to be evolved from adaptations of the fishes to the deepening and oligotrophic development of the lake.According to the data in living spaces,the adults of all species can be divided into three types,they are:coastal dwellers,offshore mid-upper dwellers and offshore mid-lower dwellers.However,the larvae of all species live together in coastal zone of the lake.Differentiations in adults living spaces should be a derived characters and represent their adaptation to the deepening and oligotrophic development of the lake.The habits of larvae in living spaces should be an original characters and suggest that the ancestors of extant fishes be hill-stream dwellers.This differentiation in living spaces can be shown as Fig.1.When comparing to their congeners,most fishes share a slower growth rate,a more slender body and a small body size (Table 1,2,3,4,5).The oligotrophic development of the lake must have lead food shortage to the fishes.It was the increasing food shortage that had caused the fishes to grow more slowly and to form a smaller body size.The fishes of the lake are characterized by having long spawning seasons and the existence of a regular interval between the spawning activities of any two breeding populations.These breeding habits can ensure that the limited spawning sites would be fully used and that the limited food resources would be effectively used by the larvae.Some species of fishes have relatively lower individual fecundities than their congeners.This is closely related to the oligotrophic development of the lake.Increasing food shortage can usually cause fishes to have lower individual fecundities.The sexual ratios of most species show great disparity and the females are usually dominant in a population (Table 6).It is those differentiations mentioned above that have resulted in the diverse extant fishes of Fuxian Lake.
The morphology,silverline system and infraciliature of a soil ciliate collected from South Africa,Acineria uncinata Tucolesco,1962 were reinvestigated with light and scanning electron microscopic methods.The results demonstrate that:(1) all three perioral kineties have a structure of monokinetids,of which the PK[2] extends only to the anterior 1/3 of the body length,(2) the short dorsal brush consisting of about 10 pairs of basal bodies is not connected with any other somatic ciliary rows,(3) apart from those along the cytostome,the extremely closely set extrusomes are arranged at the most anterior end of the cell and (4) the compressed oral slit are anteriorly "rolled up "and overlapping to the left side forming an oblique spoon-like excavation.The general morphology of this species shows very similar appearances to the original descriptions given by Tucolesco:it has 4-5 kineties (mostly 4!) on the right side (including the 2 perioral kineties),usually 4 (seldom 5) unciliated left kineties (including the dorsal brush and perioral kinety 1) but constant two macronucleus segments which are sometimes very closely connected together.It is still unclear yet whether the short slit-like cytostome is really restricted to the rolled up anterior end (only) as the original author reported,this character could not be confirmed in our observations.
Generally,gibbons are monogamous and territorial,mean group size is about four.But with the disputable species of black-crested gibbon (Hylobates concolor) based on recent ecological studies,the mean group size vairied from 3 to 7 or 8 according to different studies,and the mating system was considered to be monogamous or polygynous (Xu et al.,1983;Haimoff et al.,1986;Liu,1988;Lan,1989).This article mainly deals with the black-gibbons group size and composition,after a 10-month survey of black-crested gibbons in Wuliang and Ailao Reserve,Yunnan Province.We concluded from seven groups in 4 sites that mean group size is 4.3,each group has 1 adult male,1-2 adult females,and 1-3 offspring of various ages.The group size and composition is similar with that of Hainan black-crested gibbon reported by Xu et al(1983) and Liu (1988),but the results show some differences with Haimoff et al (1986) and Lan (1989).The group size and compositioon are quite correlated with the habitat,e.g.,GC1 group and GD group live in the less disturbed area,each maintians a group of six or seven individuals including two adult females respectively,and GG group only has one adult female and one subadult male because of heavy hunting presure and forest cutting in their habitat,althouth they live in more than 200 hm[2].
From April,1988 to December,1992,8 investigations on soil beetles are conducted under the vegetations of Pinus massoniana,laurilignosa and aestilignosa,Pinus taiwanensis and shrub-meadow of Jiuhua Mountains respectivcly.417 specimens were collectd,which belong to 33 families.Among them,220 individuals are larvas,which belong to 15 families;197 individuals are adults,which belong to 28 families,64 species (genera).The average density is 705 individuals/m[3].Melolonthidae (L) and Elateridae (L) are dominant genera.18 kinds are common genera,which belong to Curculionidae (L),Staphylinidae (L),Platystethus operosus (A) and Longitasus succinens (A),etc.With increase of elevation,the habitat condition emerges vertical changes obviously,which results in the difference on the community structure of soil beetles.The richness,evenness and domiance indexes of community composition are all higher under the vegetations of mixed forest and shrub-meadow,than those under the vegetations of Pinus taiwanensis and Pinus massoniana;the difference is considerable among each community composition,Jaccard similarity index is small.Species (genera) which appears in only one habitat are more,but the common species (genus) are fewer.Changes of individual number are not totally identical with genera number.The density of soil beetles under the vegetation of Pinus taiwanensis is higest,which is 1083.2 individuals/m[3] averagely,however,the density under Pinus massoniana is lowest,which is 652.8/m[3],But the seasonal changes of number in each habitat are different,the number under Pinus taiwanensis is more only in winter,and fewer in other seasons;numbers under shrub-meadow and mixed forest are steadier.As regards seasonal changes of species (genera) number and individual number of soil beetles,the general trend is winter>artumn>spring>summer.The individual number of larva is 2 times more than adults,but the individual number of adults is 2.5 times more than larvats in mixed forest.The law of vertical distribution of soil beetles in soil bed is obvious,that is,many genera and individuals centralize in A layer,and obviously decreasing downwards.Individual numbers in A layer constitute 56.8% averagely.This is not same in four seasons,the individual number of A layer is the most in summer,constitutes 67.5%;in spring is lowest,constitutes 38.3%.Families which mainly distribute in A layer are Staphylinidae(A),Curculionidae (A),Chrysomelidae (A),Leiodidae (A),Tenebrionidae (A),Monommatidae (A),Scaphidiidae,Silphidae (L) etc.Genera which only distribute in D layer are very few,only Dermestidae (A) and Hydrophilidae (L).
Comparisons of biomass time series data on 17 species populations of the desert rodents inhabiting the experimental study site in the Chihuahuan Desert are presented.Time series analysis,Shannon index of evenness and seasonality index are used for assessing allocation patterns of the total community biomass among 17 species populations and the role of dispersal in the patterns.The results suggest that two dominant species,Dipodomys merriami and D.spectabilis,played significant role in stabling the community total biomass and other non-dominant species subsidized community biomass when biomass of the dominants was low.Dispersal,one of the conspicuous traits of life history of desert rodents,contributed to the patterns and played an important role in the coexistence of 17 species.
The present paper deals with the characteritics of ovarian stages and the breeding habits of a freshwater catfish Leiocassis longirostris Gunther in the Jialing River.According to the external shape and histological featrues,development of the ovary is divided into six stages:1.oogonia;2.oocyte with follicular epithelium consisting of a single layer of follicle cells;3.oocyte with yolk vesicles;4.oocyte filled with yolk;5.complete maturation;6.degeneration of oocyte.Stage Ⅰ of ovaries can be seen one year old fishes only.The stage Ⅱ lasts about 2 years and then develops into the stage Ⅲ,Ⅳ,Ⅴ before maturation.Age at first maturity is 3 years old.Ovarian annual changes of adult fish only undergo the stages Ⅱ-Ⅵ.The spawning period is from April to June.After spawning,the ovaries quickly degenerate to the stage Ⅱ and then develop to the stage Ⅲ again.Each year the catfish has a single spawning season,in which the female is confirmed to spawn once.Many nucleoli are observed in oocytes.They can be divided into 2 types I.e.large and small.The sticky membrane of eggs is derived from the follicle cells.Degeneration of the atretic follicle and the resorption of yolk in Leiocassis longirostris is subdivided into five consecutive stages.
In order to determine the biological role of antisperm IgA,especially secretory IgA,in immunological infertility and in the development of an antisperm contraceptive vaccine,a panel of monoclonal IgA (moIgA) antibodies to lactate dehydrogenase C4 (LDH-C4) were prepared by intraintestinal immunization,and their heterogeneous isoforms were demonstrated by Western blotting.Most moIgAs (PA1-PA5) were obtained by the combined use of intraintestinal immunization and fusion of Peyers patch cells for parent cells.In the presence of guinea pig serum complement,mouse sperm were immobilized by moIgA PA1,PA2 and PA4.Mouse sperm were agglutinated by PA4 and PA5 at high concentration.The rates of in vitro fertilization were significantly reduced by 3 of 7 moIgA tested,but moIgA (PA1,PA2 and PA5) had no significant effects on mouse in vivo fertilization by passive immunization.Purified murine bile secretory component was assembled with either purified moIgA or moIgA in ascites in vitro.The effects of moIgA on sperm immobilization,sperm agglutination and in vitro fertilization were not significantly changed following the binding of the moIgA with secretory component.These results provide direct evidence of a positive biological role of anti-LDH-C4 moIgA and secretory IgA in sperm function and in vitro fertilization.
By use of polycrylamide gel electrophoresis.The patterns of expression of LDH isozymes were investigated in six differentialed adult tissue (eye,brain,heart,kidney,liver,and muscle) and the early developmental stages (from zero to 120 h after fertilizied) of Vaicorhinus sp.The results show that:1) During the early developmetal stages LDH-A genes and LDH-B genes exhibited at the same time.Five LDH zones were found.In comparison with most other teleosts,the patternes of expression of LDH isozymes of Varicorhinus sp.have its characteristic during the early developmental stages.The gene activities are equal between A and B.2)Isozymes genes in adult Varicorhinus sp.apparently exhibit a tissue-specific expression.The LDH-C gene is only present in liver and it migrates to the cathode.Theses LDH-C4.The above results provide basic information for the biochemical genetic survey of Varicorhinus sp.populations and artificial breeding of Varicorhinus sp.
In this exploration,agarose isoelectrofocusing,SDS-Polyacrylamide gel electrophoresis and two- dimensional electrophoresis method by their combination were used for the comparative study of introspecific evolutionary relationship of the wild crucian and five varieties of goldfishes.The results as follows.(1) A great quantity of the muscle proteins of the wild crucian and the goldfishes are similar,which verifies the inference that goldfishes were evolved from the wild crucian.(2) In course of the evolution from the wild crucian to goldfishes,appeared some component parts of proteins,and some disappeared,and moreover,there is a tendency of this evolution,golden crucian being the transitional link.(3) Its shown by the results of the cluster analyses and patterns of electrophoreses that the wild crucian has evoled,first to golden crucian,second to grass goldfish.Through these two links,it has evoled to wen goldfishes,and at last,two close groups.dragon-eye goldfishes (such as red dragon-eye goldfish) and oval goldfishes (such as red-head oval goldfish) have emerged.
The karyotypes of seven species of Clupeiform and Perciform fishes have been studied from kidney and spleen cells by means of injection of colchicine,hypotonic treatment and air-dry technique.The results are as follows.According to this study and other literitures,we discussed the evolution of the karyotypes of Clupeifrom fishes and compared the karyotypes of the related fishes in the order of Perciformes.
The karyotypes of Phrynocephalus alboineatus,P.grumgrizimaloi and P.theobaldi were reported used by the method of chromosome preparation directly of marrow cells.P.theobaldi had 2 n=22I+26 m with NF=48,the others had 2 n=22I+24 m with NF=46.The karyotypes of three species were compared with those of other species in the same genus.It was speculated that there were at least two karyotype-group in Phrynocephalus,furthermore,the existence of two karyotype-group was possibly associated with the hypothesis given by Ananjeva in 1992 of two originating centers of Phrynocephalus.The species originated from "Central Asia" center mostly belong to the first karyotype-group having 2 n=46=22I+24 m with NF=46 whereas those from 2 "Middle Asia" Center belong to the second karyotype-group having 2 n=48=22I+26 m with NF=48.The tendency of karyotype evolution in Phrynocephalus was discussed.It was considered the ancients of Phrynocephalus having karyotype,2n=48,then changed and divided to two karyotype-branch,2n=46 and 2n=48.Among them,P.grumgrizimaloi,P.helioscopus,P.axillaris,P.versicolor and P.mystaceus were the derivated species.The difference between the karyotypes of the two populations in P.grumgrizimaloi was possibly revealed the geographical divergence of their genetic construction.The karyotypes of Phrynocephalus genus comparing with other genera in Agamidae proved the primitive taxonomical position in the family.