Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of birds.Understanding these effects is crucial for bird conserv...Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of birds.Understanding these effects is crucial for bird conservation.Reeves’ s Pheasant(Syrmaticus reevesii) is a threatened species endemic to China,which is characterized by female-only incubation.However,there is a lack of information regarding the impact of weather conditions on clutch size and incubation behavior in this species.Using satellite tracking,we tracked 27 wild female Reeves’ s Pheasants from 2020 to 2023 in Hubei Province,China.We explored their clutch size and incubation behavior,as well as their responses to ambient temperature and precipitation.Clutch size averaged 7.75 ±1.36,had an association with average ambient temperature and average daily precipitation during the egglaying period,and was potentially linked to female breeding attempts.Throughout the incubation period,females took an average of 0.73 ±0.46 recesses every 24 h,with an average recess duration of 100.80 ±73.37 min and an average nest attendance of 92.98 ±5.27%.They showed a unimodal recess pattern in which nest departures peaked primarily between 13:00 and 16:00.Furthermore,females rarely left nests when daily precipitation was high.Recess duration and nest attendance were influenced by the interaction between daily mean ambient temperature and daily precipitation,as well as day of incubation.Additionally,there was a positive correlation between clutch size and recess duration.These results contribute valuable insights into the lifehistory features of this endangered species.展开更多
To explore the nest survival rate of Reeves＇ s pheasant（Syrmaticus reevesii） and the nest-site factors that affect it, we conducted artificial nest experiments with reference to natural nests at Dongzhai National N...To explore the nest survival rate of Reeves＇ s pheasant（Syrmaticus reevesii） and the nest-site factors that affect it, we conducted artificial nest experiments with reference to natural nests at Dongzhai National Nature Reserve（DNNR）, Henan Province and Pingjingguan, Hubei Province from April to June 2014 simulating the situation in its early and later breeding season. We also determined distance characteristics of the nest sites by Arc GIS 10.0. Nest survival models were constructed in Program MARK for data analysis. Results indicated that in the early breeding season, the apparent survival rate（ASR） in DNNR（52.4%） was significantly greater than that in Pingjingguan（13.5%）, and the ASR in the later breeding season in DNNR（26.7%） was not indistinctively correlated with Pingjingguan（3.2%）. The daily survival rate（DSR） in the later breeding season was 93.8% in DNNR and 92.0% in Pingjingguan, respectively. The DSRs were both negatively correlated with nest distance to forest edges and settlements. The DSR in Pingjingguan was positively correlated with nest distance to paths and negatively correlated with nest distance to water sources. However, the DSR in DNNR was negatively correlated with nest distance to paths but positively correlated with nest distance to water sources.展开更多
Temperature-dependent sex determination（TSD） is a type of environmental sex determination in which the sex of the embryos depends on the ambient temperature; however,the molecular mechanisms governing this process r...Temperature-dependent sex determination（TSD） is a type of environmental sex determination in which the sex of the embryos depends on the ambient temperature; however,the molecular mechanisms governing this process remain unknown.Aromatase,encoded by the cyp19a1 gene,which converts androgens into estrogens in animals,was considered to be the key gene for TSD.In this study,the 5＇-flanking region of the cyp19a1 gene in Reeves＇ turtle（Mauremys reevesii） was cloned,and the promoter region was identified using the luciferase reporter assay.Then the eggs of Reeves＇ turtle were incubated at different temperatures（26°C： male-biased temperature; 29°C： non-sex-biased temperature and 32°C： female-biased temperature）.During the thermosensitive period,the adrenal kidney gonad complexes（AKG） were sampled.DNA methylation analysis of the AKG samples showed that the promoter region of the cyp19a1 gene was significantly de-methylated in the female-biased temperature regime（P＆lt;0.01）.Quantitative analysis of the cyp19a1 gene and estrogen by q PCR and Elisa assay showed that the expression level of the cyp19a1 gene and estrogen content were both upregulated significantly at the female-biased temperature（P＆lt;0.01）.These results indicated that the de-methylation response of the cyp19a1 gene to incubation temperature,especially at the female-biased temperature,could lead to temperature-specific expression of aromatase and increased estrogen levels,which may further determine gonadal development in Reeves＇ turtle.These findings provide insights into the genetic mechanisms underlying TSD.展开更多
We recorded locomotor performance of Reeves＇ butterfly lizards（Leiolepis reevesii） on a racetrack and to describe hindlimb kinematic patterns and to evaluate the effect of speed on hindlimb kinematics. The studied ...We recorded locomotor performance of Reeves＇ butterfly lizards（Leiolepis reevesii） on a racetrack and to describe hindlimb kinematic patterns and to evaluate the effect of speed on hindlimb kinematics. The studied lizards predominantly used quadrupedal locomotion at relatively low speeds, but ran bipedally with a digitigrade posture at high speeds. Speed was positively correlated with both stride length and stride frequency, and was negatively correlated with duty factor. Lizards modulated speed probably by a combination of changing frequency and amplitude of limb movements. Within the range of standardized speeds from 50 to 150 cm/s, speed effects on 28 out of a total of 56 kinematic variables were significant. The hip height at footfall increased as speed increased, whereas the amplitude of vertical oscillations of the hip did not vary with speed. The total longitudinal and dorsoventral movements relative to the hip varied with speed for all parts of the limb that were distal to the knee, whereas the lateral movements did not. The knee and ankle angle at footfall varied with speed, but did not at the end of stance. The degree of pelvis rotation during the entire stride cycle did not vary with speed. Our results suggest that pelvic rotation and femoral protraction/retraction have a minor role in modulating speed in L. reevesii.展开更多
Haliotis diversicolor Reeve is one of the most important mollusks cultured in South China. Preliminary genetic linkage maps were constructed with amplified fragment length polymorphism (AFLP) markers. A total of 2 596...Haliotis diversicolor Reeve is one of the most important mollusks cultured in South China. Preliminary genetic linkage maps were constructed with amplified fragment length polymorphism (AFLP) markers. A total of 2 596 AFLP markers were obtained from 28 primer combinations in two parents and 78 offsprings. Among them, 412 markers (15.9%) were polymorphic and segregated in the mapping family. Chi-square tests showed that 151 (84.4%) markers segregated according to the expected 1:1 Mendelian ratio (P<0.05) in the female parent, and 200 (85.8%) in the male parent. For the female map, 179 markers were used for linkage analysis and 90 markers were assigned to 17 linkage groups with an average interval length of 25.7 cm. For the male map, 233 markers were used and 94 were mapped into 18 linkage groups, with an average interval of 25.0 cm. The estimated genome length was 2 773.0 cm for the female and 2 817.1 cm for the male map. The observed length of the linkage map was 1 875.2 cm and 1 896.5 cm for the female and male maps, respectively. When doublets were considered, the map length increased to 2 152.8 cm for the female and 2 032.7 cm for the male map, corresponding to genome coverage of 77.6% and 72.2%, respectively.展开更多
As concrns fletcher-Reeues algorithm,Powell showed its convergence in the case of ex- act linear search.In 1985,Al-Baali proved its conver gence when a parameter b2belangs to (0,1/ 2)for inexact linear search.and an o...As concrns fletcher-Reeues algorithm,Powell showed its convergence in the case of ex- act linear search.In 1985,Al-Baali proved its conver gence when a parameter b2belangs to (0,1/ 2)for inexact linear search.and an open problem was presented for b2 [1/2,1).recently,Lin et al(1993)proved the case if b2=1/2,In this paper,the open problem is solved.展开更多
基金supported by the National Natural Science Foundation of China (grant number 31872240)。
文摘Weather conditions play a pivotal role in embryo development and parental incubation costs,potentially impacting the clutch size and incubation behavior of birds.Understanding these effects is crucial for bird conservation.Reeves’ s Pheasant(Syrmaticus reevesii) is a threatened species endemic to China,which is characterized by female-only incubation.However,there is a lack of information regarding the impact of weather conditions on clutch size and incubation behavior in this species.Using satellite tracking,we tracked 27 wild female Reeves’ s Pheasants from 2020 to 2023 in Hubei Province,China.We explored their clutch size and incubation behavior,as well as their responses to ambient temperature and precipitation.Clutch size averaged 7.75 ±1.36,had an association with average ambient temperature and average daily precipitation during the egglaying period,and was potentially linked to female breeding attempts.Throughout the incubation period,females took an average of 0.73 ±0.46 recesses every 24 h,with an average recess duration of 100.80 ±73.37 min and an average nest attendance of 92.98 ±5.27%.They showed a unimodal recess pattern in which nest departures peaked primarily between 13:00 and 16:00.Furthermore,females rarely left nests when daily precipitation was high.Recess duration and nest attendance were influenced by the interaction between daily mean ambient temperature and daily precipitation,as well as day of incubation.Additionally,there was a positive correlation between clutch size and recess duration.These results contribute valuable insights into the lifehistory features of this endangered species.
基金supported by the Forestry Commonweal Program(201404422)the National Natural Science Foundation of China(31172115)
文摘To explore the nest survival rate of Reeves＇ s pheasant（Syrmaticus reevesii） and the nest-site factors that affect it, we conducted artificial nest experiments with reference to natural nests at Dongzhai National Nature Reserve（DNNR）, Henan Province and Pingjingguan, Hubei Province from April to June 2014 simulating the situation in its early and later breeding season. We also determined distance characteristics of the nest sites by Arc GIS 10.0. Nest survival models were constructed in Program MARK for data analysis. Results indicated that in the early breeding season, the apparent survival rate（ASR） in DNNR（52.4%） was significantly greater than that in Pingjingguan（13.5%）, and the ASR in the later breeding season in DNNR（26.7%） was not indistinctively correlated with Pingjingguan（3.2%）. The daily survival rate（DSR） in the later breeding season was 93.8% in DNNR and 92.0% in Pingjingguan, respectively. The DSRs were both negatively correlated with nest distance to forest edges and settlements. The DSR in Pingjingguan was positively correlated with nest distance to paths and negatively correlated with nest distance to water sources. However, the DSR in DNNR was negatively correlated with nest distance to paths but positively correlated with nest distance to water sources.
基金supported financially by the National Natural Science Foundation of China(Nos.31401053 and 31471966)Guangdong Provincial Natural Science Foundation of China(No.2015A030313903)+1 种基金GDAS Special Project of Science and Technology Development(2017GDASCX-0107)the Funds for Environment Construction and Capacity Building of GDAS’Research Platform(2016GDASPT-0107)
文摘Temperature-dependent sex determination（TSD） is a type of environmental sex determination in which the sex of the embryos depends on the ambient temperature; however,the molecular mechanisms governing this process remain unknown.Aromatase,encoded by the cyp19a1 gene,which converts androgens into estrogens in animals,was considered to be the key gene for TSD.In this study,the 5＇-flanking region of the cyp19a1 gene in Reeves＇ turtle（Mauremys reevesii） was cloned,and the promoter region was identified using the luciferase reporter assay.Then the eggs of Reeves＇ turtle were incubated at different temperatures（26°C： male-biased temperature; 29°C： non-sex-biased temperature and 32°C： female-biased temperature）.During the thermosensitive period,the adrenal kidney gonad complexes（AKG） were sampled.DNA methylation analysis of the AKG samples showed that the promoter region of the cyp19a1 gene was significantly de-methylated in the female-biased temperature regime（P＆lt;0.01）.Quantitative analysis of the cyp19a1 gene and estrogen by q PCR and Elisa assay showed that the expression level of the cyp19a1 gene and estrogen content were both upregulated significantly at the female-biased temperature（P＆lt;0.01）.These results indicated that the de-methylation response of the cyp19a1 gene to incubation temperature,especially at the female-biased temperature,could lead to temperature-specific expression of aromatase and increased estrogen levels,which may further determine gonadal development in Reeves＇ turtle.These findings provide insights into the genetic mechanisms underlying TSD.
基金supported by grants from the National Natural Science Foundation of China (project no. 30860046)Nanjing Normal University
文摘We recorded locomotor performance of Reeves＇ butterfly lizards（Leiolepis reevesii） on a racetrack and to describe hindlimb kinematic patterns and to evaluate the effect of speed on hindlimb kinematics. The studied lizards predominantly used quadrupedal locomotion at relatively low speeds, but ran bipedally with a digitigrade posture at high speeds. Speed was positively correlated with both stride length and stride frequency, and was negatively correlated with duty factor. Lizards modulated speed probably by a combination of changing frequency and amplitude of limb movements. Within the range of standardized speeds from 50 to 150 cm/s, speed effects on 28 out of a total of 56 kinematic variables were significant. The hip height at footfall increased as speed increased, whereas the amplitude of vertical oscillations of the hip did not vary with speed. The total longitudinal and dorsoventral movements relative to the hip varied with speed for all parts of the limb that were distal to the knee, whereas the lateral movements did not. The knee and ankle angle at footfall varied with speed, but did not at the end of stance. The degree of pelvis rotation during the entire stride cycle did not vary with speed. Our results suggest that pelvic rotation and femoral protraction/retraction have a minor role in modulating speed in L. reevesii.
基金Supported by the National Basic Research Program of China (973 Program) (Nos. 2010CB126405 and 2009CB126005)the Key Project for International Science and Technology Cooperation, Ministry of Science and Technology of China (No. 2004DFA07200)+2 种基金the Great Science and Technique Program of Hainan Province (No. 06120)the Hainan Key Laboratory of Tropical Hydrobiological Technology (No. shkyjj0810)supported by the Rutgers University
文摘Haliotis diversicolor Reeve is one of the most important mollusks cultured in South China. Preliminary genetic linkage maps were constructed with amplified fragment length polymorphism (AFLP) markers. A total of 2 596 AFLP markers were obtained from 28 primer combinations in two parents and 78 offsprings. Among them, 412 markers (15.9%) were polymorphic and segregated in the mapping family. Chi-square tests showed that 151 (84.4%) markers segregated according to the expected 1:1 Mendelian ratio (P<0.05) in the female parent, and 200 (85.8%) in the male parent. For the female map, 179 markers were used for linkage analysis and 90 markers were assigned to 17 linkage groups with an average interval length of 25.7 cm. For the male map, 233 markers were used and 94 were mapped into 18 linkage groups, with an average interval of 25.0 cm. The estimated genome length was 2 773.0 cm for the female and 2 817.1 cm for the male map. The observed length of the linkage map was 1 875.2 cm and 1 896.5 cm for the female and male maps, respectively. When doublets were considered, the map length increased to 2 152.8 cm for the female and 2 032.7 cm for the male map, corresponding to genome coverage of 77.6% and 72.2%, respectively.
文摘As concrns fletcher-Reeues algorithm,Powell showed its convergence in the case of ex- act linear search.In 1985,Al-Baali proved its conver gence when a parameter b2belangs to (0,1/ 2)for inexact linear search.and an open problem was presented for b2 [1/2,1).recently,Lin et al(1993)proved the case if b2=1/2,In this paper,the open problem is solved.
