نتایج جستجو برای: bald

تعداد نتایج: 926  

Journal: :Proceedings of the National Academy of Sciences of the United States of America 2015
Bernhard Voelkl Steven J Portugal Markus Unsöld James R Usherwood Alan M Wilson Johannes Fritz

One conspicuous feature of several larger bird species is their annual migration in V-shaped or echelon formation. When birds are flying in these formations, energy savings can be achieved by using the aerodynamic up-wash produced by the preceding bird. As the leading bird in a formation cannot profit from this up-wash, a social dilemma arises around the question of who is going to fly in front...

2017
H. G. SMITH J. M. KEENER

This paper, an annotated list of Ohio's rare and endangered vertebrate species, was compiled to supplement a similar national list and includes 10 mammals, 62 birds, 10 reptiles, 4 amphibians, and 33 fishes. Where possible, suggestions are made both as to causes of the rare or endangered status of these species and as to means of halting the trend. Ratings of "endangered," "rare," "peripheral,"...

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