bluuebunny/crossref_metadata_2025_split huggingface dataset:
Carotenoid concentration and coloration of American Kestrels (Falco sparverius) disrupted by experimental exposure to PCBs
Authors: Bortolotti Gary R. , Fernie Kimberly J. , Smits Judit E. 
Published: October 2003

Summary

Bright coloration in birds is typically a sexually selected trait. Expression of such traits is sensitive to environmental factors, so they can function as bioindicators of environmental contamination. Of particular value may be carotenoid‐based coloration because it is commonly used as a social signal and these pigments have important health functions.
American Kestrels (Falco sparverius) in captivity were exposed to dietary PCBs in March. Colour and plasma carotenoids of exposed and control birds were evaluated at pairing and courtship in April, and in winter in December. Juveniles produced by these birds (exposed to PCBs only in ovo) were examined at fledging and in winter.
The brightly coloured ceres and lores were evaluated by comparison to colour charts and quantified using digital photographs, and plasma carotenoid concentrations were quantified by spectrophotometry.
During breeding, PCB‐exposed kestrels differed from controls for both colour and carotenoids, although the nature of effects was sex‐specific. Carotenoids of juveniles were not related to treatment at fledging.
In winter, PCB‐exposure resulted in patterns of colour/carotenoid variation opposite to controls; exposed adult males were duller, and juveniles of both sexes were brighter, than controls. PCB juveniles had higher plasma levels of carotenoids. Sexual dimorphism was apparent in colour and carotenoids of control adults, but not for PCB‐exposed birds.
Our results are consistent with endocrine disruption. Modulation of both colour and carotenoids may have serious consequences to social behaviour and health.
Gender differences in lifespan and mortality rates in two seed beetle species
Authors: Fox C. W. , Dublin L. , Pollitt S. J. 
Published: October 2003

Summary

In most animals, females live longer than males, and large individuals live longer than small individuals. We examine both gender and body size effects on adult lifespan in two species of seed beetles (Callosobruchus maculatus and Stator limbatus), and test whether body size differences between males and females can explain gender‐differences in mortality rates and lifespan.
In both species, the effect of age on mortality rate was best described by a logistic mortality curve. C. maculatus females have a higher initial mortality rate than males, while males have a much higher rate of increase of the mortality rate with increasing age. In contrast, S. limbatus males had a higher initial mortality rate (opposite to the pattern seen in C. maculatus) but males and females did not differ in the rate of increase of mortality with increasing age.
Body size was positively correlated with lifespan in both species, but it explained very little of the variance in lifespan (R2 < 0·09 for both species) and did not explain the gender difference.
Lifespan was heritable for both genders of both populations (h2 between 0·19 and 0·55), and the shape of the mortality curves varied among families within both species.
Distribution, status and ecology of the mainland slender‐tailed treeshrew Dendrogale murina
Authors: TIMMINS R. J. , DUCKWORTH J. W. , ROBSON C. R. , WALSTON J. L. 
Published: October 2003

ABSTRACT 1. The few historical records of Dendrogale murina are from southern Vietnam, South‐east Thailand and probably Cambodia. Recent records extend its range considerably further north in Vietnam, into Laos, and provide the first certain Cambodian localities. Its occurrence within its range is patchy, and while in some areas (Cat Tien National Park, Vietnam, and a part of Mondulkiri Province, Cambodia) it is clearly common, elsewhere records are infrequent. Dendrogale murina seems to be relatively easy to observe, so the documented range for Laos, Vietnam and Thailand probably approximates to the real range. Cambodia has not been surveyed extensively enough to propose a provisional distribution. 2. There is no obvious ecological correlate of species occurrence: most sites have extensive bamboo, but various other similar sites surveyed within its range lack records. Most records come from evergreen forest (at varying stages of degradation) but D. murina has also been found in mixed deciduous forest, extensive secondary bamboo lacking any dicotyledonous canopy, and in streamside tangles amid rocky savannah. Records range from the plains up to 1500 m altitude. 3. The species mainly uses the under‐ and mid‐storeys, but also enters the canopy. It is active at least throughout the daylight hours; nocturnal activity has not been assessed. Although the ecological needs are poorly understood, there is no reason to believe that D. murina is at any special risk and it is unlikely to meet any IUCN global threat criteria.
Field metabolic rate and body water turnover of the red fox Vulpes vulpes in Australia
Authors: WINSTANLEY ROY K. , BUTTEMER WILLIAM A. , SAUNDERS GLEN 
Published: October 2003

ABSTRACTWe measured the daily energy expenditure of free‐living red foxes Vulpes vulpes occupying a temperate region of New South Wales, Australia. Field metabolic rate (FMR) and body water turnover were estimated using doubly labelled water. In autumn, male body mass ranged from 5 to 6.1 kg (mean 5.6 kg) and their FMRs averaged 2328 kJ/day. Female body mass in autumn ranged from 4.9 to 6.6 kg (mean 5.4 kg) and their FMRs averaged 1681 kJ/day. Body water influx for males and females was 314 and 251 mL/day, respectively. Body composition of each fox was analysed after the field measurements and revealed a significant correlation between body water content, as estimated from tritiated water space, and body lipids (r2 = 0.72). This supports the use of body water determination as a potentially non‐destructive method to gauge body condition.
Eavesdropping on the echolocation and social calls of bats
Authors: FENTON M. B. 
Published: October 2003

ABSTRACT 1. Comparisons of original calls and their echoes allow echolocating microchiropteran bats to collect information about their surroundings. Echolocation calls are also a source of information for other animals. A spectacular example is the hearing‐based defence of many species of insects that use echolocation calls to detect marauding bats. The role of echolocation calls remains unknown for bats that eat other bats. 2. Other eavesdroppers, biologists, regularly monitor echolocation calls to collect information about the distribution and patterns of habitat use of echolocating bats. People monitoring echolocation calls have discovered cryptic species of bats. 3. Vocal communication in bats involves social calls that serve only in communication, as well as echolocation calls that influence the behaviour of conspecifics and others. There is evidence of individual‐ and colony‐specific social and echolocation calls. 4. The long age‐spans of bats and the propensity of some species to roost in groups combine with conspicuousness of echolocation calls to set the stage for the discovery of more behavioural interactions mediated by individual‐specific echolocation calls. In the echolocation of microchiropteran bats, signals can serve multiple functions, both for producers and listeners.
Burrowing rodents as ecosystem engineers: the ecology and management of plateau zokors Myospalax fontanierii in alpine meadow ecosystems on the Tibetan Plateau
Authors: ZHANG YANMING , ZHANG ZHIBIN , LIU JIKE 
Published: October 2003

ABSTRACT 1. Plateau zokors, Myospalax fontanierii, are the only subterranean herbivores on the Tibetan plateau of China. Although the population biology of plateau zokors has been studied for many years, the interactions between zokors and plants, especially for the maintenance and structure of ecological communities, have been poorly recognized. In the past, plateau zokors have been traditionally viewed as pests, competitors with cattle, and agents of soil erosion, thus eradication programmes have been carried out by local governments and farmers. Zokors are also widely and heavily exploited for their use in traditional Chinese medicine. 2. Like other fossorial animals, such as pocket gophers Geomys spp. and prairie dogs Cynomys spp. in similar ecosystems, zokors may act to increase local environmental heterogeneity at the landscape level, aid in the formation, aeration and mixing of soil, and enhance infiltration of water into the soil thus curtailing erosion. The changes that zokors cause in the physical environment, vegetation and soil clearly affect the herbivore food web. Equally, plateau zokors also provide a significant food source for many avian and mammalian predators on the plateau. Zokor control leading to depletion of prey and secondary poisoning may therefore present problems for populations of numerous other animals. 3. We highlight the important role plateau zokors play in the Tibetan plateau ecosystem. Plateau zokors should be managed in concert with other comprehensive rangeland treatments to ensure the ecological equilibrium and preservation of native biodiversity, as well as the long‐term sustainable use of pastureland by domestic livestock.
Temperature and humidity in badger Meles meles setts
Authors: MOORE JUDE A. H. , ROPER TIMOTHY J. 
Published: October 2003

ABSTRACT 1. Temperature and relative humidity were measured within 12 badger Meles meles setts over periods ranging from 24 hours to 1 year. 2. Relative humidity was 100% within all setts at all times of year. Mean daily, monthly and annual within‐sett temperature ranges were 0.37°C, 1.5°C and 10.7°C, respectively, and were significantly less than the corresponding ambient temperature ranges of 8.9°C, 19.0°C and 24.1°C. 3. There was no evidence that the temperature regime of main setts differed from that of outlier setts. Within a single large main sett, temperatures taken simultaneously at different sampling points differed by up to 2.5°C. The temperature of nest chambers that were occupied by a badger was, on average, 2.4°C higher than in unoccupied chambers. 4. We conclude that: (i) variation in within‐sett temperature and humidity is not sufficient to explain the complex way in which badgers use the setts available to them; and (ii) the environmental conditions within badger setts are such as would be expected to favour the survival of bovine tuberculosis Mycobacterium bovis bacilli.
Mixed species groups in mammals
Authors: STENSLAND EVA , ANGERBJÖRN ANDERS , BERGGREN PER 
Published: October 2003

ABSTRACT1. Mixed species groups have long been noted in birds, but they also occur among different species of mammals ranging from closely related species to species from different orders. Mixed species groups of mammals occur in many different habitats, e.g. ungulates on the savannah, primates in various types of forests and cetaceans in the oceans. Mixed species groups are very different in their duration, frequency, predominant activity and structure depending on the species interacting and the habitat they occur in.2. Functional explanations for mixed species groups usually fall within two categories: foraging advantages and predator avoidance. However, there could also be other social and reproductive advantages of mixed species groups that could contribute to their formation and stability. The advantages do not have to be equally distributed between the participating species and can also vary according to season and the presence of predators.3. It is important that all investigators of mixed species groups take their studies one step further after the naturalistic description and test the function and benefits of mixed species groups in order to give more strength to their conclusions. In this paper we review and discuss the function of mixed species groups in mammals and suggest an approach on how to investigate the function of such groups.
Ecology, status and conservation of short‐beaked common dolphinsDelphinus delphisin the Mediterranean Sea
Authors: BEARZI GIOVANNI , REEVES RANDALL R. , NOTARBARTOLO‐DI‐SCIARA GIUSEPPE , POLITI ELENA , CAÑADAS ANA , FRANTZIS ALEXANDROS , MUSSI BARBARA 
Published: October 2003

ABSTRACT1. The recent decline in the Mediterranean population of short‐beaked common dolphinsDelphinus  delphis  has  been  the  subject of scientific controversy  and  political  indifference. Research on these animals has been very limited and there has been no large‐scale, systematic effort to assess and monitor their abundance and distribution. The consequent lack of data has prevented a good understanding of historical and ongoing trends.2. Nonetheless, literature and osteological collections confirm that common dolphins were widespread and abundant in much of the Mediterranean Sea until the late 1960s and that their decline occurred relatively quickly. Today, common dolphins remain relatively abundant only in the westernmost portion of the basin (Alboràn Sea), with sparse records off Algeria and Tunisia, concentrations around the Maltese islands and in parts of the Aegean Sea, and relict groups in the south‐eastern Tyrrhenian and eastern Ionian Seas. Otherwise, these dolphins are rare in, or completely absent from, Mediterranean areas where information is available.3. Circumstantial evidence and qualitative judgements by the authors suggest that the following factors may have contributed to the decline of common dolphins: reduced availability of prey caused by overfishing and habitat degradation; contamination by xenobiotic chemicals resulting in immunosuppression and reproductive impairment; environmental changes such as increased water temperatures affecting ecosystem dynamics; and incidental mortality in fishing gear, especially gillnets. The cumulative importance of these factors is poorly understood, and as a result, few conservation measures have been implemented.4. This paper reviews current knowledge and suggests priorities for action aimed at identifying and mitigating the main threats to common dolphins in the Mediterranean, with the ultimate goal of restoring the species’ favourable conservation status in the region.
Distribution of the Clymene dolphin Stenella clymene
Authors: FERTL DAGMAR , JEFFERSON THOMAS A. , MORENO IGNACIO B. , ZERBINI ALEXANDRE N. , MULLIN KEITH D. 
Published: October 2003

ABSTRACT 1. The Clymene dolphin Stenella clymene is found in tropical and warm temperate waters of both the North and South Atlantic Oceans. Confusion surrounding the identifying characteristics of this species has contributed to a general lack of knowledge of this species. 2. We collected and verified a total of 195 records (109 sightings, 67 strandings, and 19 captures) of Clymene dolphins. Twenty‐five per cent (n = 49) of these records were previously unpublished. Rejected records are discussed in order to clarify the literature. 3. The northernmost locations for the Clymene dolphin are 39°17′N, 74°35′W (NJ, USA) and 19°1.9′N, 16°13.5′W (113 km north of Nouakchott, Mauritania). The southernmost locations are 29°58′S, 50°07′W (Tramandaí, Rio Grande do Sul, Brazil) and 3°40′S, 18°5′W (off Ascension Island). 4. Clymene dolphins were found in waters with bottom depths ranging from 44 to 4500 m (mean = 1870 m; SE = 110 m; median = 1675 m; n = 94). A single sighting reported at a location with a bottom depth of 44 m is considered to be atypical, as this species has an otherwise exclusively oceanic distribution. 5. Group sizes ranged from at least one individual in a mixed‐species school of spinner dolphins Stenella longirostris to a group of an estimated 1000 animals (mean = 76.1; SE = 11; median = 47; n = 105). Stranding group size ranged from 1 to 46 individuals (n = 67), with single individuals being most common (n = 60). There is information available for seven mass strandings, all of which occurred in the south‐eastern USA.
Inheritance of resistance to the ‘Kanpur’ race of Phytophthora drechsleri in pigeonpea
Authors: Singh I. P. , Chaudhary R. G. , Katiyar P. K. , Dua R. P. , Robbelen G. 
Published: October 2003

Abstract Phytophthora drechsleri causes stem blight, which is one of the most serious diseases of pigeonpea. Eight races of this fungus have been identified, but the inheritance of resistance to all these races is not clear except for race P2. This study examined the inheritance of resistance to race ‘Kanpur’ (KPR) of P. drechsleri in eight crosses involving four resistant parents, viz.‘KPBR 80‐2‐1′, ‘KPBR 80‐2‐2′, ‘Hy 3C and ‘BDN 1′, and two susceptible parents, viz.‘Bahar’ and ‘PDA 10′. The reactions of the parental lines, and their F1, F2 and backcross generations were studied in an infected plot. In the F1 generation of all crosses, a susceptible reaction was observed that indicated dominance of susceptibility over resistance. The segregation pattern in F2 indicated that two homozygous recessive genes (pdr1pdr1pdr2pdr2) were responsible for imparting resistance in the parents, ‘KPBR 80‐2‐1’ and ‘KPBR 80‐2‐2′, and that a single homozygous recessive gene (pdrpdr) was responsible for resistance in the parents ‘Hy 3C and ‘BDN 1′. Therefore, ‘KPBR 80‐2‐1’ and ‘KPBR 80‐2‐2’ with two genes for resistance are better donors because the resistance transferred from them will be more durable compared with ‘Hy3C and ‘BDN1’ with only one gene for resistance.
All hermaphrodite progeny are derived by self‐pollinating the sunrise papaya mutant
Authors: Chan‐Tai C. , Yen C.‐R. , Chang L.‐S. , Hsiao C.‐H. , Ko T.‐S. , Weber W. E. 
Published: October 2003

AbstractSelf‐pollination of a hermaphroditic cultivar normally gives a ratio of 2 : 1 hermaphrodite to female papayas with genotypes M2m and mm, respectively. Much effort has been dedicated to marking the sexual types of papaya at the seedling stage to distinguish hermaphroditic from female papayas. A hermaphroditic papaya mutant (SR*) has been obtained, derived from the ‘Sunrise’ papaya cultivar mutant. Self‐pollination of the mutant resulted in all progenies being hermaphroditic. The genotype of the female was lethal, as a result of a lethal gene being linked to the mm female gene complex in this case. However, a 3 : 1 segregation ratio was obtained from the progeny of the hermaphroditic cultivar ‘Thailand’ crossed with SR*, indicating that all genotypes survived. Homozygous genotypes (M2M2) would be lethal according to Storey's model. Randomly selected F1 plants of the ‘Thailand’ SR* combination were self‐pollinated to obtain an F2 generation. The F2 segregation ratio suggested that the SR* mutant had a different form of the M2 allele, now designated as M@, which allowed the dominant M@M2 to survive in cross combinations. Genetic study has proved that SR* has the M@ml genotype, a new mutant. It is capable of producing all hermaphroditic papaya progenies.
Random amplified polymorphic DNA variation within and among meadow bromegrass progeny types
Authors: DE Araújo M. R. A. , Coulman B. , Somers D. , Ferdinandez Y. , Rakow G. 
Published: October 2003

AbstractTen meadow bromegrass genotypes tested as half‐sib (polycross, PX; open‐pollinated, OP) and selfed (S1) progenies were surveyed using random amplified polymorphic DNA. Fourteen primers, which produced 32 markers, were selected to determine the genotypes of 360 individuals from the three progeny tests. Analysis of molecular variance was performed in each progeny test, and genetic distances between genotypes and progeny types were determined. Among genotype genetic variation in half‐sib (PX and OP) progenies was similar. Genetic variation among genotypes for S1 progenies (30.5%) was about twice that found in the half‐sib progenies. Variation between individual S1 progenies ranged from 15.7% to 50.1%, while in the half‐sib progenies, the range was 6.9‐24.1%. Based on average distances between progeny types for a given genotype, OP and PX were closer to each other than to the S1. An analysis of variance of the molecular marker frequency occurrence was performed for 12 plants within each progeny type of each genotype. Marker frequencies, expressed in percentages, ranged from 10.7% to 84.3%. No significant differences were found for genotype and progeny type‐genotype interaction suggesting that all genotypes behave in a similar manner across the different progeny types.
Pleiotropic effect of the dwarfing gene d18‐k on cool tolerance at booting stage under the genetic background of an extremely cool‐tolerant line Norin‐PL8 in rice
Authors: Murai M. , KC H. B. , Gima N. , Jung C. 
Published: October 2003

AbstractNorin‐PL8 (‘PL8’) is an extremely cool‐tolerant line of rice in Japan that contains genes for cool tolerance originating from a javanica landrace. It was investigated to see whether the dwarfing gene d18‐k (kotaketamanishiki dwarf) exerts its pleiotropic effect on enhancing the cool tolerance at the booting stage in the genetic background of PL8. The d18‐k isogenic line of the recurrent parent PL8 (D8), PL8, and two commercial cultivars ‘Hayayuki’ and ‘Kirara 397’ were used. For each line/cultivar, the 12°C‐5‐day treatment was conducted at various times during the booting stage. In addition to spikelet fertility, the ratio (%) of the fertilized‐spikelet number of each treated panicle to the varietal mean of fertilized‐spikelet number per panicle in the control (FS‐T/C) was adopted to estimate cool temperature damage. For FS‐T/C, the lines‐cultivars ranked in the order of D8 > PL8 > ‘Hayayuki’ > ‘Kirara 397’, reflecting their cool tolerances. D8 exceeded PL8 in both pollen grain number per anther in the control and as an indicator of pollen fertility after the treatment, as a result of the effects of d18‐k. Consequently, d18‐k can be used to develop super‐highly cool‐tolerant cultivars for cool‐weather areas.
Inheritance and chromosomal location of Septoria passerinii resistance introgressed from Hordeum bulbosum into Hordeum vulgare
Authors: Toubia‐Rahme H. , Johnston P. A. , Pickering R. A. , Steffenson B. J. , Graner A. 
Published: October 2003

AbstractSeptoria speckled leaf blotch (SSLB), caused by Septoria passerinii, has become one of the most serious diseases of barley in the Upper Midwest region of the USA. The recombinant line 36L5 derived from a backcross of the susceptible barley cultivar ‘Emir’ and a resistant Hordeum bulbosum parent Cb2920/4/Colch was found to be resistant to S. passerinii. Two doubled haploids derived from 36L5 were backcrossed to cv.‘Emir’ to obtain two BCF2 populations for determining the inheritance of resistance to S. passerinii. BCF2 progeny and BCF2:3 families were evaluated at the seedling stage in the greenhouse for reaction to S. passerinii. BCF2 progeny and BCF2:3 families from both crosses segregated 3 : 1 (resistant : susceptible), and 1:2:1 (resistant : segregating : susceptible), respectively, indicating that the H. bulbosum‐derived SSLB resistance is conferred by a single dominant gene. The H. bulbosum introgressions were positioned on chromosome 4HL by genomic and fluorescent in situ hybridizations (GISH and FISH, respectively) and by Southern hybridization with the rye repetitive sequence pSc119.2. These findings indicate that SSLB resistance in H. bulbosum has the potential to be transferred and utilized in barley breeding programs.