Animal vectors of Arceuthobiumamericanum seed in Manitoba

1989 ◽  
Vol 19 (7) ◽  
pp. 865-869 ◽  
Author(s):  
David Punter ◽  
Jeannie Gilbert

Long-distance dispersal of Arceuthobiumamericanum Nutt. ex Engelm. seed by animals was investigated in Grand Beach Provincial Park, Manitoba, where passerine migration routes traverse stands of dwarf mistletoe infected Pinusbanksiana Lamb. Small mammals appear to be insignificant as vectors in Manitoba as no seeds were found on any of the 193 individuals trapped. In contrast, 5.5% of 146 birds netted in 1986 and 5.1% of 59 netted in 1987 carried seed. Three species are reported carrying seed for the first time: brown creeper (Certhiaamericana), Swainson's thrush (Catharusustulatus), and red-breasted nuthatch (Sittacanadensis). Seeds were also found on five gray jays (Perisoreuscanadensis) and three dark-eyed juncos (Juncohyemalis), species for which numerous records of dwarf mistletoe seed transport already exist. Swainson's thrushes and dark-eyed juncos are potential disseminators of A. americanum seed into jack pine stands in northern Ontario and the Great Lakes States during years when seed discharge and migration overlap.

PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4353 ◽  
Author(s):  
Xin Wang ◽  
Lei Cao ◽  
Inga Bysykatova ◽  
Zhenggang Xu ◽  
Sonia Rozenfeld ◽  
...  

The degree of inhospitable terrain encountered by migrating birds can dramatically affect migration strategies and their evolution as well as influence the way we develop our contemporary flyway conservation responses to protect them. We used telemetry data from 44 tagged individuals of four large-bodied, Arctic breeding waterbird species (two geese, a swan and one crane species) to show for the first time that these birds fly non-stop over the Far East taiga forest, despite their differing ecologies and migration routes. This implies a lack of suitable taiga refuelling habitats for these long-distance migrants. These results underline the extreme importance of northeast China spring staging habitats and of Arctic areas prior to departure in autumn to enable birds to clear this inhospitable biome, confirming the need for adequate site safeguard to protect these populations throughout their annual cycle.


PeerJ ◽  
2018 ◽  
Vol 6 ◽  
pp. e4304 ◽  
Author(s):  
Dongping Liu ◽  
Guogang Zhang ◽  
Hongxing Jiang ◽  
Jun Lu

Migratory birds often follow detours when confronted with ecological barriers, and understanding the extent and the underlying drivers of such detours can provide important insights into the associated cost to the annual energy budget and the migration strategies. The Qinghai-Tibetan Plateau is the most daunting geographical barrier for migratory birds because the partial pressure of oxygen is dramatically reduced and flight costs greatly increase. We analyzed the repeated migration detours and habitat associations of four Pallas’s Gulls Larus ichthyaetus across the Qinghai-Tibetan Plateau over 22 migration seasons. Gulls exhibited notable detours, with the maximum distance being more than double that of the expected shortest route, that extended rather than reduced the passage across the plateau. The extent of longitudinal detours significantly increased with latitude, and detours were longer in autumn than in spring. Compared with the expected shortest routes, proximity to water bodies increased along autumn migration routes, but detour-habitat associations were weak along spring migration routes. Thus, habitat availability was likely one, but not the only, factor shaping the extent of detours, and migration routes were determined by different mechanisms between seasons. Significant between-individual variation but high individual consistency in migration timing and routes were revealed in both seasons, indicating a stronger influence of endogenous schedules than local environmental conditions. Gulls may benefit from repeated use of familiar routes and stopover sites, which may be particularly significant in the challenging environment of the Qinghai-Tibetan Plateau.


Botanical interest in the islands of the southern ocean has centred largely on the geographical relationships of their floras, problems of long-distance dispersal, and on the larger questions which their floras raise concerning the past distribution of land and sea in the southern hemisphere and the origins and migration-routes of the continental floras (references in Turrill 1953, pp. 184-88). This paper will deal with the vegetation types of the southern islands. The major types of native vegetation on the islands are compared with one another, and with similar types on the southern continents, and some of the ecological consequences of their insularity are discussed. Geographically, the islands considered all lie between the Tropic of Capricorn and the Antarctic Circle (figure 10). With the exception of the mid-Atlantic and mid-Indian Ocean groups, all he within about a thousand kilometres of the nearest continental shelves. Most of them consist wholly or partly of volcanic material. Islands of both continental and oceanic origin (Wallace 1895) are included. Their climates are all extremely oceanic, with small temperature ranges, evenly distributed rainfall, constantly high humidities, and strong westerly winds. Air temperatures at sea level closely follow those of the surrounding seas (figure 11).


2019 ◽  
Vol 104 (1) ◽  
pp. 33-48 ◽  
Author(s):  
Alejandro Zuluaga ◽  
Martin Llano ◽  
Ken Cameron

The subfamily Monsteroideae (Araceae) is the third richest clade in the family, with ca. 369 described species and ca. 700 estimated. It comprises mostly hemiepiphytic or epiphytic plants restricted to the tropics, with three intercontinental disjunctions. Using a dataset representing all 12 genera in Monsteroideae (126 taxa), and five plastid and two nuclear markers, we studied the systematics and historical biogeography of the group. We found high support for the monophyly of the three major clades (Spathiphylleae sister to Heteropsis Kunth and Rhaphidophora Hassk. clades), and for six of the genera within Monsteroideae. However, we found low rates of variation in the DNA sequences used and a lack of molecular markers suitable for species-level phylogenies in the group. We also performed ancestral state reconstruction of some morphological characters traditionally used for genera delimitation. Only seed shape and size, number of seeds, number of locules, and presence of endosperm showed utility in the classification of genera in Monsteroideae. We estimated ancestral ranges using a dispersal-extinction-cladogenesis model as implemented in the R package BioGeoBEARS and found evidence for a Gondwanan origin of the clade. One tropical disjunction (Monstera Adans. sister to Amydrium Schott–Epipremnum Schott) was found to be the product of a previous Boreotropical distribution. Two other disjunctions are more recent and likely due to long-distance dispersal: Spathiphyllum Schott (with Holochlamys Engl. nested within) represents a dispersal from South America to the Pacific Islands in Southeast Asia, and Rhaphidophora represents a dispersal from Asia to Africa. Future studies based on stronger phylogenetic reconstructions and complete morphological datasets are needed to explore the details of speciation and migration within and among areas in Asia.


2021 ◽  
pp. 1-18
Author(s):  
Wen-Yi Huang

Abstract Using received texts and excavated funerary epitaphs, this article examines the intricacies of gender and migration in early medieval China by exploring women's long-distance mobility from the fourth century to the sixth century, when what is now known as China was divided by the Northern Wei and a succession of four southern states—the Eastern Jin, Liu-Song, Southern Qi, and Liang. I focus on three types of migration in which women participated during this period: war-induced migration, family reunification, and religious journeys. Based on this analysis, I propose answers to two important questions: the connection between migration and the state, and textual representations of migrants. Though the texts under consideration are usually written in an anecdotal manner, the references to women, I argue, both reveals nuances in perceptions of womanhood at the time and elucidates the contexts within—and through—which long-distance travel became possible for women.


2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Melquizedec Luiz Silva Pinheiro ◽  
Cleusa Yoshiko Nagamachi ◽  
Talita Fernanda Augusto Ribas ◽  
Cristovam Guerreiro Diniz ◽  
Patricia Caroline Mary O´Brien ◽  
...  

Abstract Background The Scolopacidae family (Suborder Scolopaci, Charadriiformes) is composed of sandpipers and snipes; these birds are long-distance migrants that show great diversity in their behavior and habitat use. Cytogenetic studies in the Scolopacidae family show the highest diploid numbers for order Charadriiformes. This work analyzes for the first time the karyotype of Actitis macularius by classic cytogenetics and chromosome painting. Results The species has a diploid number of 92, composed mostly of telocentric pairs. This high 2n is greater than the proposed 80 for the avian ancestral putative karyotype (a common feature among Scolopaci), suggesting that fission rearrangements have formed smaller macrochromosomes and microchromosomes. Fluorescence in situ hybridization using Burhinus oedicnemus whole chromosome probes confirmed the fissions in pairs 1, 2, 3, 4 and 6 of macrochromosomes. Conclusion Comparative analysis with other species of Charadriiformes studied by chromosome painting together with the molecular phylogenies for the order allowed us to raise hypotheses about the chromosomal evolution in suborder Scolopaci. From this, we can establish a clear idea of how chromosomal evolution occurred in this suborder.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Yi Huang-Takeshi Kohda ◽  
Zhaojie Qian ◽  
Mei-Fang Chien ◽  
Keisuke Miyauchi ◽  
Ginro Endo ◽  
...  

AbstractPteris vittata is an arsenic (As) hyperaccumulator plant that accumulates a large amount of As into fronds and rhizomes (around 16,000 mg/kg in both after 16 weeks hydroponic cultivation with 30 mg/L arsenate). However, the sequence of long-distance transport of As in this hyperaccumulator plant is unclear. In this study, we used a positron-emitting tracer imaging system (PETIS) for the first time to obtain noninvasive serial images of As behavior in living plants with positron-emitting 74As-labeled tracer. We found that As kept accumulating in rhizomes as in fronds of P. vittata, whereas As was retained in roots of a non-accumulator plant Arabidopsis thaliana. Autoradiograph results of As distribution in P. vittata showed that with low As exposure, As was predominantly accumulated in young fronds and the midrib and rachis of mature fronds. Under high As exposure, As accumulation shifted from young fronds to mature fronds, especially in the margin of pinna, which resulted in necrotic symptoms, turning the marginal color to gray and then brown. Our results indicated that the function of rhizomes in P. vittata was As accumulation and the regulation of As translocation to the mature fronds to protect the young fronds under high As exposure.


The Auk ◽  
2021 ◽  
Author(s):  
Scott F Lovell ◽  
M Ross Lein ◽  
Sean M Rogers

Abstract Eastern (Vireo gilvus gilvus) and western (V. g. swainsoni) forms of the Warbling Vireo have essentially allopatric breeding ranges across north-central North America, but come into contact in central Alberta, Canada. In 1986, Jon Barlow presented preliminary morphological and song evidence suggesting that the Warbling Vireo complex might comprise more than one valid species. However, to date, Barlow’s suggestion is supported by only limited DNA evidence, demonstration of molt and migration differences between the taxa, and anecdotal accounts of differences in song, morphology, plumage, and ecology. We analyzed variation in both mitochondrial and nuclear DNA in birds from Alberta and surrounding areas to determine the levels of genetic differentiation and hybridization occurring in the contact zone, and whether the two taxa warrant recognition as separate biological species. Our analyses reveal that Warbling Vireos in Alberta and the surrounding areas are separated into two well-defined, genetically differentiated, and monophyletic clades corresponding to previously recognized taxonomic groups. The two taxa come into contact in a narrow (~85 km) zone in Barrhead County, northwest of Edmonton, Alberta. They show evidence of limited hybridization. The distinct genetic differences are maintained in the contact zone, where individuals of the two taxa may occupy neighboring territories. Differences in spring arrival dates, molt schedules, and migration routes indicate that a migratory divide may play an important role in reproductive isolation. We suggest that the two taxa are distinct cryptic species: an eastern form, Vireo gilvus, and a western form, Vireo swainsoni.


2014 ◽  
Vol 11 (99) ◽  
pp. 20140542 ◽  
Author(s):  
Nathan F. Putman ◽  
Erica S. Jenkins ◽  
Catherine G. J. Michielsens ◽  
David L. G. Noakes

Animals navigate using a variety of sensory cues, but how each is weighted during different phases of movement (e.g. dispersal, foraging, homing) is controversial. Here, we examine the geomagnetic and olfactory imprinting hypotheses of natal homing with datasets that recorded variation in the migratory routes of sockeye ( Oncorhynchus nerka ) and pink ( Oncorhynchus gorbuscha ) salmon returning from the Pacific Ocean to the Fraser River, British Columbia. Drift of the magnetic field (i.e. geomagnetic imprinting) uniquely accounted for 23.2% and 44.0% of the variation in migration routes for sockeye and pink salmon, respectively. Ocean circulation (i.e. olfactory imprinting) predicted 6.1% and 0.1% of the variation in sockeye and pink migration routes, respectively. Sea surface temperature (a variable influencing salmon distribution but not navigation, directly) accounted for 13.0% of the variation in sockeye migration but was unrelated to pink migration. These findings suggest that geomagnetic navigation plays an important role in long-distance homing in salmon and that consideration of navigation mechanisms can aid in the management of migratory fishes by better predicting movement patterns. Finally, given the diversity of animals that use the Earth's magnetic field for navigation, geomagnetic drift may provide a unifying explanation for spatio-temporal variation in the movement patterns of many species.


2012 ◽  
Vol 26 (1) ◽  
pp. 61-72 ◽  
Author(s):  
Renata Piwowarczyk

Abstract Orobanche coerulescens has a Eurasian distribution. The species is classified as extinct at most of its localities at the western limit of its range. Its populations are very scarce and critically endangered in Central Europe. This work presents the current distribution of O.coerulescens in Poland, based on a critical revision of herbarium and literature data as well as results of original field research, and reviews its distribution in Central Europe (partly in Eastern Europe). Habitats, plant communities, and migration routes of O.coerulescens in Central Europe are discussed. The species was initially known in Poland from now historical localities in Pomerania and the valley of the lower Vistula. In 2000-2011 it was recorded at 9 localities in Podlasie, the Małopolska Upland (Wyżyna Małopolska), and the Łódź Hills (Wzniesienia Łódzkie). Its abundance at the localities ranged from a few to over 1000 shoots. These are the largest populations of O.coerulescens at its western and north-western range limits.


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