Frank Gill

• Doctor of Philosophy
• Professor Emeritus at Academy of Natural Sciences of Drexel University

The polytypic species concept unites populations that theoretically could and would interbreed were the opportunity to arise-This concept places the burden of proof of reproductive in-capability and species status on those claiming species or higher rank. Advances in our understanding of the nature of reproductive isolation, the genetics of speciat...

Revision of 1999 account

Eight species of parids commonly occur in the mountains of northern Sichuan Province, People's Republic of China. They represent four monophyletic groups regarded by some authorities as genera, but more traditionally as subgenera of the large genus Parus. To test the competition-based hypothesis that less closely related species are more likely to...

We summarize the history of the varied practices of hyphenating compound English names of birds to highlight taxonomic relationships. English names do not and can not reflect phylogenetic relationships of birds very well, however lofty that ideal. Instead, English names of birds are driven more by tradition than by modern systematics; the consequen...

We present a phylogenetic hypothesis for 40 species in the bird family Paridae, based on comparisons of nucleotide sequences of the mitochondrial cytochrome-b gene. Parids, including tits and chickadees, are an older group than their morphological stereotypy suggests. The longest cytochrome-b distances between species reach 12% in uncorrected diver...

SummaryA description is given of Rodriguez, the most remote of the Mascarene Islands, and of its avifauna, with special reference to the two surviving endemic land-birds.

Hummingbirds in the tropical rainforests of southwestern Costa Rica face intense competition from stingless bees Trigona that steal nectar from hummingbird flowers. Here we document both interference and exploitative competition between bees and hummingbirds at scarlet, hummingbird pollinated flowers of Passiflora vitifolia. Aggressive stingless be...

http://deepblue.lib.umich.edu/bitstream/2027.42/57084/1/OP648.pdf

We present a phylogenetic hypothesis for 40 species in the bird family Paridae, based on comparisons of nucleotide sequences of the mitochondrial cytochrome-b gene. Parids, including tits and chickadees, are an older group than their morphological stereotypy suggests. The longest cytochrome-b distances between species reach 12% in uncorrected diver...

Pseudopodoces humilis (Hume's Ground-Jay) is a small passerine bird that inhabits the high rocky steppes of the Tibetan (Qinghai–Xizang) Plateau. Although it was long classified as a small species of ground jay (Podoces), two previous anatomical studies cast doubt on its assignment to the Corvidae (crows and jays). We studied the evolutionary relat...

With their long, pointed wings and deeply forked tail, frigatebirds present a distinctive flight silhouette. They seem to soar effortlessly throughout the day and are rarely seen to flap their wings; yet their great aerial agility enables them to chase and harass other birds until the chased bird regurgitates a recently caught meal, whereupon the f...