Realized climate niche breadth varies with population trend and distribution in North American birds

2016 ◽  
Vol 25 (10) ◽  
pp. 1173-1180 ◽  
Author(s):  
Joel Ralston ◽  
William V. DeLuca ◽  
Richard E. Feldman ◽  
David I. King
Agronomy ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 2133 ◽  
Author(s):  
Timothy A. Dickinson ◽  
Brigitte Xueqi Yan ◽  
Shery Han ◽  
Mehdi Zarrei

We compare biogeographic and morphological parameters of two agamic complexes of western North American hawthorns so as to evaluate possible explanations of the differences in range between sexually reproducing taxa and their apomictic sister taxa. We have documented range, breeding system, morphology, leaf vascular architecture, and niche breadth in these hawthorns, for which phylogenetic relationships and ploidy levels are known. Species distribution data from herbarium specimens and online databases were analyzed in order to compare ranges and climate niches described by bioclimatic variables. Flow cytometry documented ploidy level and breeding system. Voucher specimens provided morphometric data that were analyzed using uni- and multivariate methods. Members of two black-fruited taxonomic sections of Crataegus subg. Sanguineae (sections Douglasianae, Salignae) have previously been identified as hybrids. They are presumptively self-fertile polyploids with pseudogamous gametophytic apomixis. Their morphologies, geographic ranges, and niche characteristics resemble those of their diploid, sexual parent or are intermediate between them and those of their other parent, one or both of two partially sympatric tetraploid apomicts in red-fruited C. subg. Americanae with much wider distributions. Comparing sections Douglasianae and Salignae suggests that geographic parthenogenesis (larger range sizes in apomicts, compared to sexually reproducing taxa) may have less to do with adaptation than it does with reproductive assurance in the pseudogamously apomictic and self-compatible hybrids. Greater climate niche breadth in allopolyploids compared to diploids similarly may be more due to parental traits than to effects of genome duplication per se.


2019 ◽  
Vol 54 (1-2) ◽  
pp. 5-17 ◽  
Author(s):  
Ridma G. Bandara ◽  
Jessamine Finch ◽  
Jeffrey L. Walck ◽  
Siti N. Hidayati ◽  
Kayri Havens

2013 ◽  
Vol 182 (6) ◽  
pp. 760-774 ◽  
Author(s):  
Anna Kostikova ◽  
Glenn Litsios ◽  
Nicolas Salamin ◽  
Peter B. Pearman

2013 ◽  
Vol 83 (4) ◽  
pp. 858-865 ◽  
Author(s):  
Shannon J. McCauley ◽  
Christopher J. Davis ◽  
Earl E. Werner ◽  
Michael S. Robeson

Ecography ◽  
2012 ◽  
Vol 36 (3) ◽  
pp. 300-312 ◽  
Author(s):  
Xavier Morin ◽  
Martin J. Lechowicz
Keyword(s):  

2020 ◽  
Vol 29 (2) ◽  
pp. 259-264 ◽  
Author(s):  
Hasan K. Saleh ◽  
Paula Folkeard ◽  
Ewan Macpherson ◽  
Susan Scollie

Purpose The original Connected Speech Test (CST; Cox et al., 1987) is a well-regarded and often utilized speech perception test. The aim of this study was to develop a new version of the CST using a neutral North American accent and to assess the use of this updated CST on participants with normal hearing. Method A female English speaker was recruited to read the original CST passages, which were recorded as the new CST stimuli. A study was designed to assess the newly recorded CST passages' equivalence and conduct normalization. The study included 19 Western University students (11 females and eight males) with normal hearing and with English as a first language. Results Raw scores for the 48 tested passages were converted to rationalized arcsine units, and average passage scores more than 1 rationalized arcsine unit standard deviation from the mean were excluded. The internal reliability of the 32 remaining passages was assessed, and the two-way random effects intraclass correlation was .944. Conclusion The aim of our study was to create new CST stimuli with a more general North American accent in order to minimize accent effects on the speech perception scores. The study resulted in 32 passages of equivalent difficulty for listeners with normal hearing.


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