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101.
Phylogeography of a northeast Asian spruce, Picea jezoensis, inferred from genetic variation observed in organelle DNA markers 总被引:1,自引:0,他引:1
Aizawa M Yoshimaru H Saito H Katsuki T Kawahara T Kitamura K Shi F Kaji M 《Molecular ecology》2007,16(16):3393-3405
Range-wide genetic variation of the widespread cold-temperate spruce Picea jezoensis was studied throughout northeast Asia using maternally inherited mitochondrial DNA and paternally inherited chloroplast DNA markers. This study assessed 33 natural populations including three varieties of the species in Japan, Russia, China, and South Korea. We depicted sharp suture zones in straits around Japan in the geographical distribution pattern of mitochondrial haplotypes (GST=0.901; NST=0.934). In contrast, we detected possible extensive pollen flow without seed flow across the straits around Japan during the past population history in the distribution pattern of chloroplast haplotypes (GST=0.233; NST=0.333). The analysis of isolation by distance of the species implied that by acting as a barrier for the movement of seeds and pollen, the sharp suture zones contributed considerably to the level of genetic differentiation between populations. Constructed networks of mitochondrial haplotypes allowed inference of the phylogeographical history of the species. We deduced that the disjunction with Kamchatka populations reflects range expansion and contraction to the north of the current distribution. Within Japan, we detected phylogeographically different types of P. jezoensis between Hokkaido and Honshu islands; P. jezoensis in Honshu Island may have colonized this region from the Asian continent via the Korean peninsula and the species in Hokkaido Island is likely to have spread from the Asian continent via Sakhalin through land bridges. Japanese endemism of mitochondrial haplotypes in Hokkaido and Honshu islands might have been promoted by separation of these islands from each other and from the Asian continent by the straits during the late Quaternary. 相似文献
102.
Paired male and female eastern whipbirds, Psophodes olivaceus,sing precisely coordinated, male-led duets. Four broad explanationshave been proposed for the function of duets: 1) cooperativeresource defense, 2) prevention of partner usurpation, 3) defenseof an individual's own position within the partnership, or 4)mate identification and localization. These 4 hypotheses makedifferent predictions about how male and female residents shouldrespond to simulated intrusion by other pairs or individuals.We compared the behavioral and vocal responses of 20 pairs ofeastern whipbirds to simulated territorial intrusions by: 1)a solitary singing male, 2) a solitary singing female, and 3)a duetting pair. Males and females did not coordinate theirapproach to the playback speaker and showed sex-specific responsesto playback. Males did not respond differently to duetting versussolo singing intruders. By contrast, females approached moreclosely during solo female song than during solo male song orduet playback. Females also produced specific vocalizationsonly in response to duet and solo female playback. Both sexesapproached the speaker more closely and quickly during playbackof same-sex solo songs than opposite-sex solo songs. Finally,females answered more of their mate's songs during simulatedintrusion by a lone female than during simulated intrusion bya lone male. Our results suggest that duets in this speciesprimarily function to allow females to defend their exclusiveposition in a partnership. Mate defense by females is unusualin birds but may be promoted in eastern whipbirds by a female-biasedsex ratio and the need for exclusive access to male care. Thus,duets result from independent and conflicting strategies ofmate and territory defense in males and females. 相似文献
103.
Freshwater finfish species richness and level of endemism in East, and South and South‐East Asia that included 17 nations were studied using available databases, and included nation‐wise distribution, habitat types, and conservation status. The number of endemic finfish species in the region was 559, belonging to 47 families. Families Cyprinidae and Balitoridae accounted for 43.5% and 16.2% of the total number of endemic species in the region, respectively, followed by Sisoridae (25), Gobiidae (20), Melanotaeniidae (19), and Bagridae (16), and the other 41 families had at least one endemic species. Nation‐wise the most number of endemic freshwater finfish species occur in India (191), followed by China (88), Indonesia (84), and Myanmar (60). In India, the endemic species accounted for 26.4% of the native freshwater fish fauna, followed by South Korea (16.9%), the Philippines, (16.3%) and Myanmar (15.7%). Statistically significant relationships discerned between the number of indigenous and endemic species richness to land area (Xla in 103 km2) of the nations in the region were, Yin = 218.961 Ln(Xla) – 843.1 (R2 = 0.735; P < 0.001) and Ye = 28.445 Ln Xla?134.47 (R2 = 0.534; P < 0.01), respectively, and between indigenous and endemic species richness was Ye = 0.079Xn? 1.558 (R2 = 0.235; P < 0.05). The overall conservation status of endemic finfish in Asia was satisfactory in that only 92 species were in some state of vulnerability, of which 37 species (6.6%) are endangered or critically endangered. However, the bulk of these species (83.7%) were cave‐ and or lake‐dwelling fish. However, nation‐wise, the endemic freshwater finfish fauna of the Philippines and Sri Lanka, based on the imperilment index, were found to be in a highly vulnerable state. Among river basins, the Mekong Basin had the highest number of endemic species (31.3%). The discrepancies between databases are highlighted and the need to consolidate information among databases is discussed. It is suggested that the Mekong Basin be considered as a biodiversity hotspot, and appropriate management strategies be introduced in this regard. 相似文献
104.
105.
Frank R. Thompson III Melissa C. Roach Thomas W. Bonnot 《The Journal of wildlife management》2022,86(2):e22170
Chuck-will's-widow (Antrostomus carolinensis) and eastern whip-poor-will (Antrostomus vociferus) are nightjars in eastern North America that have declined 69% and 67%, respectively, in abundance since 1966, resulting in conservation concerns for these species. We investigated relationships between nightjar abundance and landscape composition, forest structure, and application of tree thinning and prescribed fire because of regional interest in woodland restoration and nightjar conservation. We conducted nocturnal nightjar surveys at 385 points in southern Missouri, USA, in 2014 and 2015 and related counts to pine (Pinus spp.) and hardwood basal area, canopy closure, percent forest cover, and percent of area thinned or burned within 500 m of survey points. We modeled abundance of chuck-will's-widow and eastern whip-poor-will using time-removal models that included a detection process and an abundance process within a hierarchical Bayesian framework. We detected 534 eastern whip-poor-will and 186 chuck-will's-widow during surveys. Our data supported global models that included all 6 vegetation and management variables for both species. Chuck-will's-widow abundance was negatively related to hardwood basal area and peaked at intermediate values of percent area burned and percent forest cover. Eastern whip-poor-will abundance was negatively related to hardwood basal area and canopy cover, positively related to percent forest cover and percent of area burned, and peaked at low to moderate levels of percent of area thinned. Relationships to forest structure and management activities generally supported the conclusion that woodland restoration benefits nightjars and that chuck-will's-widow select landscapes with less forest cover than eastern whip-poor-will. 相似文献
106.
【目的】本研究旨在确定四川达州白背飞虱Sogatella furcifera(Horváth)迁入虫源地及其降落机制,以期为川东地区白背飞虱预警和有效防控提供依据。【方法】运用大气质点轨迹分析平台HYSPLIT4.8对1991-2013年达州灯下白背飞虱主要迁入高峰日进行轨迹模拟,并运用气象图形处理软件Grads对主要迁入高峰日进行气象背景分析。【结果】达州白背飞虱主要在6-7月迁入,7月份是迁入高峰期。6月虫源主要来自广西西北、中部地区;7月虫源主要来自贵州中西部、北部,广西西北部和云南东北部也可提供部分虫源。【结论】四川达州白背飞虱迁入虫源主要来自贵州大部,部分来自云南东北部和广西西北部。由于气候条件和地形胁迫引起的降水、垂直气流和风向切变是白背飞虱大规模集中降落的主要原因。 相似文献
107.
Patrilineal populations show more male transmission of reproductive success than cognatic populations in Central Asia,which reduces their genetic diversity
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108.
Evolution of bilaterally asymmetrical larvae in freshwater mussels (Bivalvia: Unionoida: Unionidae)
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Bilaterally asymmetrical glochidia (i.e. bivalved parasitic larvae bearing a large marginal appendage on a single valve) have been reported from five Asian freshwater mussel genera belonging to two separate subfamilies, the Gonideinae (i.e. Pseudodon, Solenaia, and Physunio) and Rectidentinae (i.e. Contradens and Trapezoideus). This classification requires that the bilaterally asymmetrical glochidium‐bearing mussels are not monophyletic, and suggests that this atypical larval morphology evolved twice in the same geographic region. Although homoplastic glochidium characters are known (e.g. marginal appendages and size), we hypothesized that bilaterally asymmetrical glochidia represent a novel morphological synapomorphy. We tested the monophyly of the mussels bearing bilaterally asymmetrical glochidia using a molecular matrix consisting of representatives from all six freshwater mussel families and three molecular markers (28S, 16S, and COI). Bayesian inference, maximum likelihood, and ancestral state reconstruction were employed to estimate the phylogeny and larval trait transformations. The reconstructed phylogeny rejects the monophyly of the asymmetrical glochidium‐bearing mussels and resolves two putative origins of asymmetrical glochidia; however, ancestral state reconstruction supports asymmetrical glochidia as a synapomorphy of only one supraspecific taxon of the Rectidentinae. In the Gonideinae, asymmetrical glochidia were autapomorphic of Pseudodon cambodjensis (Petit, 1865). That is, no other taxa resolved among the Gonideinae had bilaterally asymmetrical glochidia, including other Pseudodon species. We describe how the alleged intrageneric glochidial variation in Pseudodon, and in the other genera of the Gonideinae reported to have asymmetrical glochidia (i.e. Solenaia and Physunio), challenge the resolved convergence of asymmetrical glochidia. Our results are discussed in the context of freshwater mussel larval evolution, patterns in life‐history traits, and the classification of freshwater mussels generally. © 2015 The Linnean Society of London 相似文献
109.
Muricea is an amphi-American genus. Verrill proposed dividing the species from the Pacific Ocean into three genera and established the genus Eumuricea for five eastern Pacific species with tubular calyces. Eumuricea is basically characterized by colonies with elongate, cylindrical calyces with truncate margins and star-like opercula, and the occurrence of unilateral spinous spindles. According to these characteristics, Eumuricea does not show enough difference from Muricea to be treated as a separate genus. Original type material of Eumuricea was morphologically analysed and illustrated using optical and scanning electron microscopy. We conclude that the eastern Pacific species should be placed in the genus Muricea and form a group characterised by tubular calyces that comprises four species at present, Muricea
acervata, Muricea
hispida, Muricea
squarrosa, and Muricea
tubigera and a dubious species Muricea
horrida. Lectotypes were designated for Muricea
squarrosa and Muricea
hispida to establish their taxonomic status. The genus Eumuricea has also been misunderstood by former authors who erroneously assigned species to it. For these species we propose new combinations: Swiftia
pusilla, Astrogorgia
splendens and Astrogorgia
ramosa. 相似文献
110.
Two new taxa of Achnanthidium and Encyonema (Bacillariophyceae) from the Yom River,Thailand, with special reference to the areolae occlusions implying ontogenetic relationship
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We discovered two new taxa of Achnanthidium and Encyonema occurring with high abundance in the upstream of the Yom River, which is one of four major rivers in Northern Thailand. Achnanthidium pseudoconspicuum var. yomensis var. nov. closely resembles Achnanthidium pseudoconspicuum var. pseudoconspicuum in scanning electron microscopy (SEM), but has clearly different valve morphometry under the light microscopy (LM). Achnanthidium pseudoconspicuum var. yomensis is also similar to A. japonicum in valve morphology under LM, but differs to this species based on SEM observation. Encyonema yuwadeeanum sp. nov. shows similarities to Encyonema leei and Encyonema subkukenanum, but differs in valve shape and/or polar fissure shape. We discuss the possible valve ontogenetic relationship between Achnanthidium and Cymbellales based on the detailed areolae structures of these two new taxa. 相似文献