皱纹盘鲍肾脏的组织化学和超微结构

以组织学、组织化学和透射电镜观察等方法研究了皱纹盘鲍（Haliotis discus hannai)的肾脏。肾脏由无数肾小管和集合管组成。肾小管上皮细胞游离面有明显的刷状缘,并有少量纤毛,细胞顶端存在大量直径为0.8-1.8μm的折光小体,组化研究显示小体内含铁。基底端质膜高度内折,并呈碱性磷酸酶活性。上皮细胞与血窦仅有基底膜相隔,细胞内最具特征性的结构是“膜囊体”,光镜下它呈嗜酸性团块,组化研究显示含丰富的蛋白质,电镜下观察它由双层单位膜围成的众多的小管及扁囊构成,小管的直径或扁囊的高度为30－80nm,某一局部的小管或扁囊的形状及排列很有规律性。“膜囊体”的性质尚不清楚。除纤毛数量增加和“膜囊体”较小一局部的小管或扁囊的形状主排列很有规律性。“膜囊体”的性质尚不清楚。除纤毛数量增加和“膜囊体”较小外,集合管上皮细胞的组织化学和超微结构类似于肾小管上皮细胞。在集合管和腔上皮还存在少量的粘液细胞。     

THE SYSTEMATIC POSITION OF THE SOUTH AFRICAN GANNET

Summary

Randall, R. M., Randall, B. M., Cooper, J. &; Frost, P. G. H. 1986: A new census method for penguins tested on Jackass Penguins Spheniscus demersus. Ostrich 57: 211–215

A census method for Jackass Penguins based on their moulting cycle is described. Population estimates were substantially higher with this method than with total counts, but were not dissimilar to maximum estimates obtained from strip counts. The moult method estimates the size of the entire population and is independent of the breeding cycle and breeding status of both individuals and population. It is not plagued by the problem of absenteeism encountered during most phases of the penguin annual cycle and is independent on their diel activity. The drawbacks to the method are that it is laborious and protracted, that it does not differentiate between the breeding population and the whole population, and is unsuited to some species and some habitats.     

4. THE SOUTH AFRICAN CLIFF SWALLOW

Short, L.L. &; Horne, J. F. M. 1980, Vocal and other behaviour of the Green Barbet in Kenya. Ostrich 51:219–229.

Brief field studies of the Green Barbet Stactolaema olivacea in coastal Kenya, with emphasis on vocalizations, document its social behaviour, including communal roosting of four birds in a cavity. Green Barbets are aggressive, interacting strongly with a number of species. Erecting of the crown feathers, cocking of the tail, and woodpeckerlike swinging movements characterize displays. Wing Flutters and audible Bill Wiping are visual-auditory displays. Vocalizations include the Grating Call, Kek Call, Chuk Call and Chowp Call. These are agonistic and agonistic-reproductive in function. The Chowp Call comprises the song, used in simultaneous singing and duetting.     

NOTES ON THE SOUTH AFRICAN SPECIES OF CORVUS

Winterbottom, J. M. 1975. Notes on the South African spscies of Corvus. Ostrich 46:236-250. The three indigenous species of Corvus in South Africa are compared in respect of geographical and ecological distribution, status, breeding, food, economic importance and general habits. Apart from the limitation of range in albicollis by its nesting requirements, it is extremely difficult to pin-point any factors in which the species so differ as to explain the paradoxes of their distribution.     

ON THE SOUTH AFRICAN RACE OF THE LITTLE SPOTTED WOODPECKER

Discriminant analysis functions have previously been determined for sexing Mediterranean Yellow-legged Gulls Larus michahellis michahellis from the western Mediterranean basin. However, data from eastern Mediterranean populations are lacking. In this work, we used morphometric data from a sample of 81 Mediterranean Yellow-legged Gulls (39 males and 42 females) breeding in the Gulf of Gabès in south-eastern Tunisia to (1) determine a discriminant function useful for sex discrimination, and (2) assess the accuracy of previously published functions in sexing Mediterranean Yellow-legged Gulls from our study area. Our results showed marked sexual differences in all morphological measurements, with males being significantly larger than females. The best discriminant function included head length, bill depth and wing length, and accurately classified 93% of sampled birds. We also found that Mediterranean Yellow-legged Gulls from the Gulf of Gabès could accurately be sexed using discriminant functions determined for another North African population, but not with a function determined for a South European population, although distances between sites are almost the same.     

TOPIARY PRUNING AND WEIGHTING REINFORCE AN AFRICAN ORIGIN FOR THE HUMAN MITOCHONDRIAL DNA TREE

A method is presented for removing recent homoplastic events from a phylogenetic tree. This “topiary pruning” method produces a series of progressively modified duplicates of the original set of data, from which more and more of the most recent substitutions have been removed. The edited sets of data have increased amounts of information per remaining taxon, while similar but randomized data sets subjected to topiary pruning do not. The ability of topiary pruning to “unscramble” artificial data sets that have high levels of homoplasy is demonstrated, and is shown to be similar in its effects to the weighting method of Kluge and Farris (1969), although with the additional advantage of reducing the number of taxa to the point where bootstrapping is feasible. Pruning and weighting used together produce closer approximations to the “true” tree than either method used separately. It is further shown that in these artificial data sets midpoint rooting is more likely to be accurate than outgroup rooting. When pruning and weighting are applied to the extensive sets of mitochondrial DNA data of Cann et al. (1987) and Vigilant et al. (1991), trees result that have deep branch points, some of which lead to entirely African branches. In the case of the Vigilant et al. data, the three African branches have bootstrap values between 0.94 and 1.0, and the consensus and bootstrap midpoint roots also have high bootstrap values and occur on these African branches near their junction. An African origin of the human mitochondrial tree is not proved by this approach, particularly since sequences from non-African groups are underrepresented in current data sets, but it is rendered more likely.     

AGE CRITERIA FOR THE AFRICAN ELEPHANT

1. The paper is based on a collection of 385 lower jaws of the African elephant (Loxodonta a. africana Blumenbach) from western Uganda. 2. Thirty age groups are described and illustrated, which are related to the progress of eruption and wear of the six teeth in each side of the lower jaw. 3. Correct identification of individual teeth in the series is essential and several checks are described. Thus, when length is plotted against width for the six teeth the points fall into six well - defined groups. Frequency distributions of laminary indices and lamella numbers support the belief that teeth have been correctly identified, but overlapping, distributions preclude identification on these characters alone. 4. The presence of abnormal seventh molars in four jaws is described. 5. Chronological ages have been assigned to the relative age groups. Information on age and growth of captive animals has been considered and the general form of the growth curve established. Arbitrary estimates of the intervals between successive age groups were made and subsequently checked against growth and seasonal ridges on the roots. These indicate an upper age limit of about 60 years, which is compatible with fuller information on Indian elephants. 6. Growth curves support the validity of the ages assigned. Asymptotic heights at shoulder (∞) are respectively 317 cm and 298 cm for males from Murchison Falls and Queen Elizabeth National Parks. For females no distinction is made (because the sample from the latter area is small) and ∞ is 272 cm. 7. Growth in weight has also been established but shows no significant differences between the two populations. The mean maximum weight of females is 2766 kg (6100 lb), and of males 5450 kg (12000 lb). Growth apparently continues throughout life. 8. Tusk growth is analysed. There is a linear increase in weight of female tusks from eruption at 1–3 years up to the oldest group, with an indicated mean combined weight of 17.7 kg (39 lb) at 60 years. Male tusks show an increasing rate of growth throughout life to a mean combined weight of about 109 kg (240 lb) at 60 years. Big tusks are generally the result of prolonged growth; extremely big tusks probably result from prolonged and above average rate of growth. 9. Seasonal and annual incremental layers on the root 3 of the teeth are briefly described; these give an objective estimate of the chronological intervals between the relative age groups. 10. Field age criteria are presented which are derived from these growth curves. 11. The age at puberty in the female elephant is discussed and compared with earlier conclusions. There is evidence of a retardation in recent years in the Murchison Falls National Park (South bank) population and of a lengthening of the mean calving interval. This considerable depression of the reproductive rate, which is almost certainly density dependent, agrees with the observed lower recruitment in this population. 12. Survivorship curves constructed from material representing 325 natural deaths are presented for the two populations. If estimates of the age at puberty and the reproductive rate are taken into account, the expected differences in recruitment are found. 13. The calculated mean expectation of life is less than 15 years. 14. Mean individual weight is estimated at about 3800 lb.     

SYSTEMATIC NOTES ON EMBERIZA CABANISI IN THE SOUTH AFRICAN SUB-REGION

Dean, W. R. J. &; Skead, D. M. 1979. Moult and mass of the Redknobbed Coot. Ostrich 50: 199–202.

The Redknobbed Coot Fulica cristata has a flightless moult throughout the year at Barberspan, but mainly during April and October/November. The flightless period is about 54 days. The plumage on the upper and under parts of the body and of the tail is replaced continually. The habitat of moulting Redknobbed Coots appears to be large open lakes; flightless birds occur singly or in small groups among full winged birds well out on open water. The mean mass of 4 016 adult Redknobbed Coots was 737 g and of 741 juveniles was 579 g, with an annual peak in adult mass in March.     

INTERACTIONS BETWEEN SOUTH AFRICAN FUR SEALS and THE PURSE-SEINE FISHERY

Operational interactions occur between South African (Cape) fur seals and the purse-seine fishery in South Africa. Seals eat fish from the nets but the main concern is the activity of seals causing fish to sound, resulting in loss, or partial loss of the catch. Detectable loss occurs on approximately 5% of hauls. In addition to this, smaller quantities may be lost on each haul as seals depress the net float line while moving into and out of the net. The cost of seal interference is difficult to quantify because the mass of fish lost is not known, and the loss is essentially one of additional fishing time required to fill the total allowable catch for the fishery. An estimate of the cost is calculated as between 1.6% and 4.1% of the landed value of the fishery. Some seals are killed by fishermen when they pose a potential threat to the safety of the crew aboard, and some may drown if caught in the net or pump. Overall this is probably fewer than a thousand seals per year. It is also known that if seals are thought to be disturbing the fish, these seals near the nets may be deliberately killed by purse-seine fishermen. Overall this mortality, whether deliberate or incidental, is probably negligible in terms of the population size of South African fur seals.     

THE EFFECT OF SEAWEED DIETS ON GROWTH OF GREEN ABALONE,HALIOTIS FULGENS,FROM BAJA CALIFORNIA,MEXICO

Two abalone species: green Haliotis fulgens and yellow Halioti corrugata represent nearly 97% of the total production in the Mexican abalone fishery. It has been assumed that abalone feed on the kelp algae Macrocystis pyrifera. Regional hatcheries use this species as a main source of natural food. M. pyrifera does not occur at the southern limit of the distribution of abalone species along the Baja California Peninsula. In this study, growth rates of juveniles H. fulgens, 17.3 ± 2.2 mm shell length and 0.4 ± 0.2 g body weight, were evaluated. Juveniles were fed with common species in the benthic environments inhabited by abalone along the western coast of Baja California during 191 days. Three diets were based on algae: palm kelp, Eisenia arborea, giant kelp, M. pyrifera and Gelidium robustum, and one on seagrass, Phyllospadix torreyi. Shell length and body growth rates varied between 21.5 μm day^?1 and 2.2 mg day^?1 for E. arborea and between 45.9 μm day^?1 and 6.7 mg day^?1 for M. pyrifera. Higher specific growth rates (SGR) in length and weight were determined for M. pyrifera: 0.2% and 0.7% day^?1. Significant differences between values of juveniles fed M. pyrifera with the rest of the diets were found. The highest mortality (21%) was in juveniles fed the red algae G. robustum.