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1.
Recent climate change is known to affect the distribution of a number of insect species, resulting in a modification of their range boundaries. In newly colonized areas, novel interactions become apparent between expanding and endemic species sharing the same host. The pine processionary moth is a highly damaging pine defoliator, extending its range northwards and upwards in response to winter warming. Its expansion in the Alps has resulted in an invasion into the range of the Spanish moon moth, a red listed species developing on Scots pine. Pine processionary moth larvae develop during winter, preceding those of the moon moth, which hatch in late spring. Using pine trees planted in a clonal design, we experimentally tested the effect of previous winter defoliation by pine processionary moth larvae upon the survival and development of moon moth larvae. Feeding on foliage of heavily defoliated trees (>50%) resulted in a significant increase in the development time of moon moth larvae and a decrease in relative growth rate compared to feeding on foliage of undefoliated trees. Dry weight of pupae also decreased when larvae were fed with foliage of defoliated trees, and might, therefore, affect imago performances. However, lower defoliation degrees did not result in significant differences in larval performances compared to the control. Because a high degree of defoliation by pine processionary moth is to be expected during the colonization phase, its arrival in subalpine pine stands might affect the populations of the endangered moon moth. 相似文献
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Picloram‐potassium and various mixtures of picloram with 2,4‐D amine, 2,4,5‐T ester or amine, or 2,4,5‐T ester alone were injected into incisions made in the cambium of standing Brachystegia spiciformis and Julbernardia globiflora trees. Each arboricide was tested at a range of application rates, at different times of the year and at three different sites for each species. Picloram‐potassium and 2,4,5‐T ester were also tested on Terminalia sericea trees. Glyphosate, MCPA, mixtures of mecoprop and 2,4,5‐T amine and different mixtures of 2,4‐D ester with 2,4,5‐T ester, cacodylic acid and Tandex were tested on B. spiciformis and J. globiflora trees at one site and only in January. Aboricides containing picloram, with or without the addition of 2,4‐D or 2,4,5‐T, were the most effective chemicals for the control of trees. Higher application rates were required to kill B. spiciformis and J. globiflora between May and October when they were not actively growing. T. sericea trees were susceptible to arboricide treatment throughout the year. The response of individual trees to treatment with arboricides appears to be related to size. 相似文献
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《African Zoology》2013,48(1):94-106
The African wild silk moth (Gonometa postica) exhibits large inter-annual population size fluctuations in the Kalahari region of southern Africa. Spent cocoons from this species are currently being utilized in a local silk industry. An understanding of the recolonization dynamics of a particular harvested site, and of the population genetic effects of such dispersal, are crucial for designing a scientifically-based harvesting strategy. I link morphological estimates of flying ability to microsatellite genotyping in the determination of dispersal ability of this species. Morphological results suggest that the moth is a poor disperser with high wing loadings and males are better fliers than females. There is a significant effect of isolation-by-distance. Spatial population genetic analyses of microsatellite data further indicate lower and upper bounds on dispersal of 90 m and 50 km. The combined evidence suggests male-biased dispersal over several dozen kilometers with females that do not disperse over large distances. I discuss the potential influences of large population size fluctuations on patterns of genetic diversity and the implications for the inference of dispersal in my study species. 相似文献
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A 6-month-old male neutered Domestic Shorthair cat was assessed for a 24-h history of anorexia, lethargy, depressed mentation, mild abdominal pain and persistent bradycardia. Abdominal ultrasound revealed marked thickening of the gastric wall, gastric distension, free abdominal fluid, distension and corrugation of the small intestine. Full-thickness histopathological biopsy of the gastric wall demonstrated intralesional chitinous structures whose morphology (size and presence of obvious barbs) supports these structures being urticating hairs (setae). A processionary caterpillar is considered most likely as these are the most common urticating caterpillars in Australia. This is the first case of suspected severe gastroenteritis associated with the ingestion of caterpillar setae fragments in a cat. 相似文献
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Food samples were collected from 49 blue petrels Halobaena caerulea at Marion Island in the sub-Antarctic region. These were analysed and the results compared with previously published data collected at other islands. Crustaceans formed the major prey by mass (59,5%) and frequency (100%), with Euphausia vallentini being of particular importance (56,6% by mass of Crustacea). Other prey included fish, cephalopods and two species of insects, a moth (Noctuidae) and an assassin bug Nabis. 相似文献
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Since 1991 the urticating hairs of the oak processionary caterpillar (Thaumetopoea processionea L.) have caused a lot of nuisance to the population and animals in a growing number of provinces in the Netherlands from June to August. Favourable climatic and nutritional factors may contribute to the mass gradation of this caterpillar. Larvae develop their urticating hairs from the third larval stage. The poisonous hairs serve as a defence mechanism against predators such as birds and small rodents. Human contact with these hairs (setae) induces dermatitis, strong cutaneous reactions (weal and flare reaction), ocular lesions and upper respiratory tract reactions by a mechanic and toxic mechanism (lepidopterism). When animals, like dogs and horses, are in direct contact with the urticating hairs due to ingestion and inhalation, the most important complaints are labial angiooedema, ptyalism, sloughing, tongue swelling, stomatitis, conjunctivitis and respiratory distress. This article describes three cases, in which animals are possibly exposed to the urticating hairs of the oak processionary caterpillar. 相似文献
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The morphology of feeding appendages of the coexisting estuarine copepods, Pseudodiaptomus hessei and Acartia longipatetla, and mysids, Rhopalophthalmus terranatalis and Mesopodopsis wooldridgei. were examined and compared as an aid in elucidating dietary differences. The robust mandibles of P. hessei copepodids compared to the more pointed and slender teeth with no molar region, of A. longipatella suggest that the latter species relies on more fragile food particles. Mandible edge indices indicate, however, omnivorous feeding by both species. No clear dietary differences could be deduced from the dimensions of the second maxillae of these copepods. Mandible edge indices calculated for the mysid species suggest a more herbivorous feeding mode in M. wooldridgei and a more carnivorous one in R. terranatalis, supporting previous studies on their diets. No interspecific differences between the mysid size classes were evident from edge indices. Significant increments in setae and setule lengths and spacing with increasing mysid size class were evident, reflecting differences in food particle sizes utilized. The morphological differences in the feeding apparatus could reflect differences in the diets between species and indicate differences in food particle sizes utilized by the various developmental stages within species. These differences in diet should reduce inter- and intraspecific competition. 相似文献
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Xiang HOU Bo ZHANG Michael A. STEELE Ning HAN Tuo FENG Jing WANG Xiaoning CHEN Xiaolei AN Gang CHANG 《Integrative zoology》2021,16(6):939-954
Animal-mediated seed dispersal is an important ecological process in which a strong mutualism between animals and plants can arise. However, few studies have examined how a community of potential seed dispersers interacts with sympatric seed trees. We employed a series of experiments in the Qinling Mountains in both semi-natural enclosure and the field to assess the interactions among 3 sympatric rodent species and 3 Fagaceae tree seeds. Seed traits all showed similar tannin levels but markedly different physical traits and nutritional contents. We found that seeds with heavy weight, thick coat, and high nutritional contents were less likely to be eaten in situ but more often to be eaten after dispersal or hoarded by rodents. These results support both the handling time hypothesis and the high nutrition hypothesis. Surprisingly, we also found that rodents, maybe, preferred to consume seeds with low levels of crude fiber in situ, and to harvest and hoard those with high levels of crude fiber for later consumption. The sympatric rodent species, Cansumys canus, the largest rodent in our study, harvested and hoarded more Quercus variabilis seeds with high physical and nutritional traits, while Apodemus draco, the smallest rodent, harvested more Q. serrata seeds with low physical and nutritional traits, and Niviventer confucianus harvested and hoarded more Q. aliena seeds with medium physical and nutritional traits. Our study demonstrates that different seed traits play different roles in influencing the seed fate and the shaping of mutualism and predation interactions within a community of rodent species. 相似文献
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Ning LI Zheng WANG Shuai ZHANG Chuan YAN Xinhai LI Changhu LU 《Integrative zoology》2019,14(5):470-478
Habitat fragmentation is globally one of the most important drivers of change in biodiversity. Seed dispersal by birds is crucial for tree regeneration in remnant patchy forests, yet how bird traits affect seed dispersal pattern is still poorly understood. We studied the extent to which bird traits affect seed‐removal networks and whether these traits affect seed deposition and seedling recruitment for 3 co‐fruiting tree species (Taxus chinensis, Cinnamomum bodinieri and Machilus thunbergii) in a patchy forest. A total of 17, 18 and 10 bird species were recorded foraging for seeds of T. chinensis, M. thunbergii and C. bodinieri, respectively. Frequency of bird visitation increased with tail length, wing length and body length. Furthermore, bird body length, bill length, body weight and wing length were important in the strength of the seed removal network. During foraging, 6 bird species exhibited different patterns of microhabitat utilization and their perching frequency increased with bird weight and tarsus length. As a consequence, frequency of habitat use, bird length and tarsus length were important in determining the number of deposited seeds. For seedling recruitment, seedling number increased with bird tarsus length and weight, but decreased with wing length. Overall, our results showed that various bird traits not only affected seed removal, but also influenced the subsequent processes of seed deposition and seedling distribution in a patchy forest. These results thus highlight the importance of large‐bodied birds for plant recruitment and point out the need to prioritize the protection and conservation of these birds in remnant patchy forests. 相似文献
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《African Journal of Range and Forage Science》2013,30(2):113-122
We examined the competitive ability and response to light (shaded or unshaded), nutrients (50% Hoaglands solution or tap water), water (frequent or infrequent watering) and cutting (cut or uncut) of four grass species that differ in their traits, habitat preferences and responses to management practices in KwaZulu-Natal. All species produced the greatest biomass in high-nutrient high-water treatments. Short to medium-height grass species, such as Themeda triandra and Aristida junciformis, produced nearly double the biomass of taller species such as Hyparrhenia hirta and Eragrostis curvula in the low-nutrient treatments, with the reverse being true in the high-nutrient treatments. Themeda triandra and A. junciformis produced the greatest root biomass both in the low- and high-nutrient treatments. The shorter species produced relatively greater root than shoot mass, with the reverse being true of the taller species. Tall species did not produce relatively less, when cut, or relatively more, when shaded, than the shorter species. However, A. junciformis and E. curvula were more shade-tolerant than the other species, suggesting that their increase in abundance with infrequent fire is due to the shading by litter in unburnt grassland. The competitive hierarchy among species reversed between low- and high-nutrient treatments, with A. junciformis and H. hirta having the greatest competitive effect on T. triandra in low- and high-nutrient treatments, respectively. These results contribute to an understanding of species distributions on fertility and burning gradients. 相似文献
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Trait allometries generate super‐honesty in Anolis dewlaps and may underlie sexual dimorphism 
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下载免费PDF全文 Whether or not sexually selected traits consistently exhibit positive allometry (i.e. are disproportionately large in larger individuals) is an ongoing debate. Multiple models and exceptions to this rule suggest that the underlying drivers of sexual trait allometry are nuanced. Here, we compare allometries of sexual and non‐sexual traits of a species (Anolis aquaticus) within a well‐studied lizard genus to test the competing hypotheses that sexual traits are, or are not, defined by positive allometry. We further consider the relationships of trait functions, which are relatively well understood in the genus Anolis, and allometry to identify potential drivers of allometric patterns. In particular, we explore how trait allometries interact to influence total organism function and generate sexual dimorphism. We quantified size (of targeted traits) and color of a sexual signal (the dewlap) in Anolis aquaticus in the field. The dewlap conveyed information relevant to intra‐sexual combat and exhibited positive allometry. Overall, our results suggest that using single‐trait allometries as indicators of past selection provides only an incomplete understanding of trait evolution. Although the function of positive allometry in some individual sexual signals (e.g. those conveying “super‐honest” information) may be straightforward, we illustrate how scaling relationships interact synergistically to influence the function of phenotypes and propose avenues for future research. 相似文献
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Cultivated walnut trees showed earlier but not final advantage over its wild relatives in competing for seed dispersers 下载免费PDF全文
下载免费PDF全文 Little is known about seeding regeneration of cultivated trees compared to wild relatives in areas where seed dispersers are shared. Here, we investigated the differences in seed fates of cultivated walnut (Juglans regia) and wild Manchurian walnut (Juglans mandshurica) trees under rodent predation and dispersal. J. regia seeds have higher nutritional value (large size, mass and kernel mass) and lower mechanical defensiveness (thin endocarp) than J. mandshurica seeds. We tracked seeds of J. regia and J. mandshurica under both enclosure and field conditions to assess differences in competing for seed dispersers of the two co‐occurring tree species of the same genus. We found that rodents preferred to harvest, eat and scatter‐hoard seeds of J. regia as compared to those of J. mandshurica. Seeds of J. regia were removed and scatter‐hoarded faster than those of J. mandshurica. Caches of J. regia were more likely to be rediscovered by rodents than those of J. mandshurica. These results suggest that J. regia showed earlier dispersal fitness but not the ultimate dispersal fitness over J. mandshurica in seeding regeneration under rodent mediation, implying that J. regia has little effect on seeding regeneration of J. mandshurica in the field. The effects of seed traits on seed dispersal fitness may vary at different dispersal stages under animal mediation. 相似文献
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Onur Yilmaz Mehmet Kizilaslan Yunus Arzik Sedat Behrem Nezih Ata Orhan Karaca Cengiz Elmaci Ibrahim Cemal 《Zeitschrift für Tierzüchtung und Züchtungsbiologie》2022,139(1):26-39
Sheep are considered as a major contributor of global food security. Moreover, sheep preweaning growth traits as well as in vivo carcass composition traits such as ultrasonic measurements of Longissimus dorsi muscle depth (UMD) and back-fat thickness (UFD) are crucially important indicators of meat yield and hot carcass composition. Despite their relative importance for productivity and profitability of a sheep production system, detected QTL for these traits are quite scarce. Therefore, we implemented GWAS for these traits using animal mixed model-based association approach provided by GenABEL in Esme sheep. Three genome-wide and 14 individual chromosome-wide associated SNPs were discovered. As a result, ESRP1, LOC105613082, ZNF641, DUSP5, TEAD1, SMOX, PTPRT, RALYL, POM121C, PHIP, LOC101106051, ZIM3, PEG3, TRPC7, FBXL4, LOC105610397, LOC105616489 and DNAAF2 were suggested as candidates. Some of the discovered genes and involved pathways were already annotated to contribute growth and development in various species including human, mice and cattle. All in all, the results of this study are expected to strongly contribute to shed a light on the underlying molecular mechanisms behind growth and carcass composition traits, with potential implications on studies aiming faster genetic improvement, targeted low-resolution SNP panel designs and genome-editing studies. 相似文献
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Elena GANGENOVA Mariano I. GIOMBINI Gustavo A. ZURITA Federico MARANGONI 《Integrative zoology》2020,15(5):428-440
Species loss by habitat replacement operating as an ecological filter is a well‐known consequence of modern human activities. In contrast, the ecological and evolutionary response of species overcoming those filters in converted habitats has not been thoroughly explored. Species that persist are subject to novel and potentially stressful conditions that may induce certain morphological changes. We evaluated changes in the functional morphology of three anuran species persisting after the conversion of areas of the Atlantic Forest into pine plantations. We specifically evaluated differences in body size and body condition indices, head width, and hind legs’ length between adult individuals from both habitats and sexes. Habitat conversion and sexual dimorphism affected the morphology of the three anurans, with varying effects upon species and traits. Regarding the effect of habitat conversion, Elachistocleis bicolor increased body condition in plantations with no changes in the other traits, Physalaemus cuvieri showed only a marginal increment in residual body mass in plantations, and Odontophrynus americanus exhibited a substantial increment in body size while maintaining its body condition in plantations. Remarkably, none of the results suggested these persistent anurans were stressed by forest conversion. This study shows that habitat conversion may induce intraspecific morphological changes in ecologically relevant traits of persistent species, and that disturbed areas do not necessarily imply stressful, low quality habitats affecting all persistent native species negatively. 相似文献
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Petra FRÝDLOVÁ Jan HNÍZDO Lenka CHYLÍKOVÁ Olga ŠIMKOVÁ Veronika CIKÁNOVÁ Petr VELENSKÝ Daniel FRYNTA 《Integrative zoology》2013,8(Z1):39-45
Blood cell morphology and count are not uniform across species. Recently, between‐species comparisons revealed that the size of red blood cells is associated with body size in some lizard taxa, and this finding was interpreted in the context of the metabolic theory. In the present study, we examined the numbers and the size of blood cells in 2 species of monitor lizards, the mangrove‐dwelling monitor (Varanus indicus) and the savannah monitor (V. exanthematicus), and we compared these traits in individuals of different body size. The results revealed that during the course of ontogeny, the size of red blood cells increases with body mass. Because the mass‐specific metabolic rate decreases with body size and the cell volume‐to‐surface ratio decreases with the cell size, changes in the erythrocyte size might be the result of oxygen transport adjustment. 相似文献
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By tracking the fate of individual seeds from 6 frugivore‐dispersed plants with contrasting seed traits in a fragmented subtropical forest in Southwest China, we explored how rodent seed predation and hoarding were influenced by seed traits such as seed size, seed coat hardness and seed profitability. Post‐dispersal seed fates varied significantly among the 6 seed species and 3 patterns were witnessed: large‐seeded species with a hard seed coat (i.e. Choerospoadias axillaries and Diospyros kaki var. silvestris) had more seeds removed, cached and then surviving at caches, and they also had fewer seeds predated but a higher proportion of seeds surviving at the source; medium‐sized species with higher profitability and thinner seed coat (i.e. Phoebe zhennan and Padus braohypoda) were first harvested and had the lowest probability of seeds surviving either at the source or at caches due to higher predation before or after removal; and small‐seeded species with lower profitability (i.e. Elaeocarpus japonicas and Cornus controversa) had the highest probability of seeds surviving at the source but the lowest probability of seeds surviving at caches due to lower predation at the source and lower hoarding at caches. Our study indicates that patterns of seed predation, dispersal and survival among frugivore‐dispersed plants are highly determined by seed traits such as seed size, seed defense and seed profitability due to selective predation and hoarding by seed‐eating rodents. Therefore, trait‐mediated seed predation, dispersal and survival via seed‐eating rodents can largely affect population and community dynamics of frugivore‐dispersed plants in fragmented forests. 相似文献
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Kensuke HIROSE Mariko NAKAMURA Tatsuya TAKIZAWA Kazuo FUKAWA Tetsuya ITO Masayuki UEDA Takashi SASAKI Kazuaki TANAKA 《Animal Science Journal》2009,80(6):624-630
An insertion/deletion variant of a thymine base (T5 and T6) in exon 2 of porcine beta 3‐adrenergic receptor (ADRB3) gene has been described. In the current study, we made an association study between the ADRB3 polymorphisms and production traits in 735 Duroc pigs. The allele frequencies for the T5 and T6 alleles in our study population were 0.433 and 0.567, respectively. Any associations between ADRB3 genotype and average daily weight gain during test period, or backfat thickness and intramuscular fat content were not detected in either sex. However the size of the loin eye muscle area (EMA) was significantly associated with ADRB3 genotypes in gilts. T6‐homozygous gilts had a higher mean of EMA (40.6 ± 0.6 cm2) than T5‐homozygous (38.1 ± 0.4 cm2, P = 0.002) and heterozygous (38.8 ± 0.3 cm2, P = 0.034) gilts. This association was not detected in males. In addition, a multiple traits animal model best linear unbiased predictor (BLUP) analysis revealed that the T6‐homozygous genotype had positive effects on breeding value of EMA. Accordingly, we suggest that ADRB3 polymorphism has the potential to be an important genetic marker for prediction of EMA in Duroc pigs. 相似文献
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Kensuke HIROSE Tatsuya TAKIZAWA Kazuo FUKAWA Tetsuya ITO Masayuki UEDA Yoichi HAYASHI Kazuaki TANAKA 《Animal Science Journal》2011,82(1):46-51
A C?T single nucleotide polymorphism (SNP) on exon 24 of the porcine class 3 phosphoinositide‐3‐kinase (PIK3C3) gene is considered a possible genetic marker for selecting backfat (BF) thickness and carcass fat, although only one study has published results on its effects by performing experiments on a single resource family. We analyzed the association of this PIK3C3 polymorphism with production traits in 739 Duroc pigs. The C allele frequency was 67.9% in our study population. PIK3C3 polymorphism showed significant effects on average daily weight gain (ADG), BF thickness, intermuscular fat content (IMF), and the size of the loin eye muscle area (EMA). The C alleles increased ADG, BF and IMF, and decreased EMA. The predicted differences in traits between the homozygous pigs of the C and T alleles were 40 g/day for DG, 1.2 mm for BF, 0.44% for IMF, and 1.6 cm2 for EMA. Furthermore, the statistical models for estimating the breeding values of each trait had lower Akaike's information criterion values when adding PIK3C3 genotype information. We therefore confirmed that the polymorphism in PIK3C3 (C2604T) has the potential to be a genetic marker for production traits in Duroc pigs. 相似文献