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151.
Factors influencing family rupture and parent-offspring conflict in the Black Kite Milvus migrans 总被引:2,自引:0,他引:2
Juvenile and adult behaviour was studied at eight nests of Black Kites Milvus migrans within the Doñana Biological Reserve, Spain. Parental investment in vigilance and defence of offspring progressively decreased during the post-fledging dependence period. The number of feeds was also slightly reduced towards the end of the period. However, this does not seem to be the main factor which leads to juvenile independence. The fact that the family rupture is sudden and that the post-fledging dependence period tends to shorten as the season progresses suggests that juvenile and adult migratory urgency may be as important a factor as reduced parental investment in breaking the family ties. 相似文献
152.
153.
FERNANDO CÉSAR WEBER ROSAS 《Mammal Review》1994,24(2):49-59
The Amazonian Manatee Trichechus inunguis (Natterer, 1883) is the only exclusively freshwater sirenian and the smallest of the living species. Its inability to reduce peripheral heat loss limits its distribution to tropical waters. The species is endemic to the Amazonian region, being distributed throughout the Amazon basin, occurring mainly in calm waters and lakes. The species has been commercially exploited since 1542, with the meat and hide being the main products extracted. This commercial exploitation, combined with their very low reproductive rate, has seriously reduced the manatee population. Therefore the Amazonian Manatee is now considered an endangered species. Although it is protected by most of the countries where it occurs, there is no law enforcement, and the species is still captured throughout the Amazon. Data on general biology, physiology and management of the Amazonian Manatee, as well as its status and recommendations for its conservation, are presented. 相似文献
154.
ALEJANDRO BOTELLO FERNANDO ALVAREZ 《Biological journal of the Linnean Society. Linnean Society of London》2010,99(2):315-325
The karstic nature of the Yucatan Peninsula promotes the formation of submerged caves and sinkholes that are inhabited by an endemic subterranean water fauna. By contrast with most other micro‐endemic stygobitic species, the freshwater palaemonid shrimp Creaseria morleyi is widely distributed across the northern part of the peninsula. In the present study, we investigated the phylogeographic structure of C. morleyi using two mitochondrial genes as markers, and explored hypotheses related to its evolution in the peninsula. DNA from 14 localities was extracted, and the 16S rRNA and cytochrome oxidase subunit I (COI) genes were amplified and sequenced. The different haplotypes were identified to construct a haplotype network and perform a nested clade analysis. Five haplotypes of the 16S gene were obtained, with a maximum divergence of 0.5%. One of these haplotypes is widely distributed and the most divergent is located in the north‐western section of the peninsula. Twelve haplotypes for the COI gene were found with a maximum divergence of 2%, showing the same spatial pattern. The analysis revealed two significantly different clades corresponding to populations in the centre and south‐east of the peninsula as a consequence of restricted genetic flow with isolation‐by‐distance. The divergence time of these two clades was 40–120 thousand years. The genetic variation in C. morleyi, the relationship between haplotypes and their geographic distribution, along with the geological history of the Yucatan Peninsula, may indicate that this variation is a relict of an ancient marked genetic structure reduced by changes in sea level that resulted in a series of bottlenecks. © 2010 The Linnean Society of London, Biological Journal of the Linnean Society, 2010, 99 , 315–325. 相似文献
155.
The genus Ilyodromus Sars, 1895 is recorded for the first time in the Oriental Region. Ilyodromus lanaoensis sp. n. is described from Mindanao, the Philippines and compared with the other species of the genus for differential diagnosis. 相似文献
156.
Osmotic shock with sequential 30 min treatments in ice-coldsaline solutions and distilled water inhibited both the subsequentuptake of orthophosphate (Pi) and its transport into the xylemof excised corn (Zea mays L.) roots. Measurements of Pi fluxeswith 32P indicated that the decrease in net Pi uptake over a24 h period caused by osmotic shock was due primarily to delayedrecovery of Pi influx rather than to increasing efflux. Despitecomplete recovery of Pi absorption within 26 h aftershocking with 150200 mM NaCl, transport to the xylemduring the subsequent 24 h only partially recovered. Leucineuptake and incorporation into protein was also markedly inhibitedby osmotic shock but both almost completely resumed controlrates within 24 h after shocking with up to 150 mM NaCl. Tetracyclineinhibited recovery of Pi uptake after NaCl treatment whereaspuromycin did not. These results with corn roots are consistentwith the hypothesis that recovery of Pi uptake activity aftermoderate osmotic shock requires de novo synthesis of membraneproteins. Incomplete recovery of Pi transport to the xylem suggeststhat osmotic shock may damage plasmodesmata. Key words: Corn, Ion uptake, Leucine uptake, NaCl, Puromycin, Tetracycline 相似文献
157.
S. MITHTHAPALA J. SEIDENSTICKER L. G. PHILLIPS S. B. U. FERNANDO J. A. SMALLWOOD 《Journal of Zoology》1989,218(4):527-536
Twenty-one captive leopards (Panthera pardus kotiya) at the National Zoological Gardens in Sri Lanka were individually identified using spot pattern variation, Based on an identification method established for lions ( Panthera leo ), a code was devised examining 23 variable characters, each of which had one to three values. These characters ranged from number and spacing of muzzle spots to forehead and eye patterns. Correlation among characters to be used for identification was minimized using principal component cluster analysis. The most variable character was chosen from each of eight non-overlapping clusters, and frequencies were calculated for each character value. The probability of occurrence of a given spot pattern was calculated as the sum of the frequencies of each character value. From this probability of occurrence, the information content, in bits, was computed for each pattern. The number of bits per character was also calculated. Using the binomial theorem, the reliability of identification was estimated as the sum of the probabilities of zero or one individual having an identical combination of character values. These binomial probabilities exceeded 0.99 for 15 out of 21 animals, and 0.95 for all but two. In these two animals, the information content was low (5.99 and 5.50 bits, respectively) compared to the others, in which information content ranged from 6.87–10.86. Although the mean number of bits (8.5) was theoretically sufficient for a 99% reliable identification, it was concluded that supplementation with an additional character would be worthwhile for identification of individual leopards. 相似文献
158.
Freshwater ostracods (Crustacea: Ostracoda) of the subfamily Dolerocypridinae Triebel, 1961 from Southeast Asia 总被引:1,自引:0,他引:1
The systematics of the freshwater ostracods of the subfamily Dolerocypridinae in Southeast Asia is reviewed: A total of five species are known and they are assigned to three genera. Astenocypris papyracea (Sars) 1903 and Dolerocypris sinensis Sars, 1903 are redescribed. Dolerocypris fasciata (Müller) 1776, from Indonesia is figured and the hitherto observed variations are discussed. Dolerocypris pellucida Klie, 1932 is transferred to the genus Tanycypris Triebel, 1959. 相似文献
159.
160.
ROBERTO DOCAMPO FERNANDO S. CRUZ WILSON LEON GABRIEL A. SCHMUNIS 《The Journal of eukaryotic microbiology》1979,26(2):301-303
Bloodstream forms of Trypanosoma cruzi had a substantial increase in respiration in the presence of acetate. Oxidation of acetate took place via the tricarboxylic acid cycle and involved an antimycin A-sensitive respiratory pathway. Oxygen uptake in the presence of acetate was as sensitive to antimycin A inhibition as was CO2 production. There was a 6–7% residual O2 uptake which was not inhibited by high antimycin concentrations. Human anti-T. cruzi sera had no effect on oxygen uptake. 相似文献