Phenetic affinities of the wood thrush, Hylocichla mustelina (Aves: Turdinae)

1976 ◽  
Vol 54 (10) ◽  
pp. 1679-1687 ◽  
Author(s):  
A. Ralph Gibson ◽  
Michael A. Gates ◽  
Reto Zach

A multivariate assessment of phenetic affinities among 11 North American and 2 European thrushes was carried out to characterize further the controversial systematic relationships of the wood thrush, Hylocichla mustelina. Principal components analysis based on 49 skeletal characters revealed that the wood thrush, which formed one of four distinct groups, was intermediate in a linear allometric series ranging from North American Catharus to European Turdus. These results, most similar to the pattern of relationships envisaged by Dorst, are discussed in terms of the findings and methodologies of previous studies. It is noted that the usual practice of interpreting principal components in terms of independent variation in size and shape is often an oversimplification.

2019 ◽  
Vol 27 (4) ◽  
pp. 211-218 ◽  
Author(s):  
Nikisha R. Patel ◽  
Susan Fawcett ◽  
Arthur V. Gilman

Since the 1970s, an apomictic tetraploid beech fern (genus Phegopteris (C. Presl) Fée) has been known in northeastern North America. Previously published isozyme data suggest that this lineage is of allopolyploid origin involving long beech fern (P. connectilis (Michx.) Watt.) but not broad beech fern (P. hexagonoptera (Michx.) Fée), as originally hypothesized. Its second progenitor remains unknown. We performed a principal components analysis of the apomict and its North American congeners to elucidate morphological differences between them. We recognize the apomictic tetraploid at specific rank as P. excelsior N. R. Patel & A. V. Gilman and provide an illustration, a range map, a list of exsiccatae, and a key to Phegopteris species of North America.


1983 ◽  
Vol 61 (3) ◽  
pp. 708-730 ◽  
Author(s):  
K. W. Nicholls ◽  
B. A. Bohm

Seventy-three taxa of the genus Lupinus in North America have been studied for their flavonoid constituents. In all, 56 compounds were isolated and either partially or totally characterized. Flavonoid types encountered were flavones, C-glycoflavones, isoflavones, flavonols, and, tentatively, flavanones. Further structural modifications seen were O-methylation, O-glycosylation at a variety of positions and acylation of several of the flavonoid glycosides. Principal-components analysis was performed on (i) presence–absence data of individual compounds with consideration given to relative concentrations and (ii) presence–absence of the types of flavonoid structures. Several groupings of taxa emerged from these analyses based upon the presence of unique compounds or combinations of compounds. In a number of these groups the chemical affinities paralleled morphological affinities closely. In all, 10 groupings were seen. Lupinus diffusus, a simple-leaved taxon from southeastern United States, stood apart from all groups.


1980 ◽  
Vol 19 (04) ◽  
pp. 205-209
Author(s):  
L. A. Abbott ◽  
J. B. Mitton

Data taken from the blood of 262 patients diagnosed for malabsorption, elective cholecystectomy, acute cholecystitis, infectious hepatitis, liver cirrhosis, or chronic renal disease were analyzed with three numerical taxonomy (NT) methods : cluster analysis, principal components analysis, and discriminant function analysis. Principal components analysis revealed discrete clusters of patients suffering from chronic renal disease, liver cirrhosis, and infectious hepatitis, which could be displayed by NT clustering as well as by plotting, but other disease groups were poorly defined. Sharper resolution of the same disease groups was attained by discriminant function analysis.


Sign in / Sign up

Export Citation Format

Share Document