by Playfuls Staff |
22nd April 2007
Your bird field guide may be out of date now that
University of Florida scientists discovered a new
genus of frogmouth bird on a South Pacific island. New genera of living birds
are rare discoveries — fewer than [more] one per year is announced globally.
David Steadman and Andrew Kratter, ornithologists at the Florida Museum of
Natural History, turned up the surprising new discovery on a collecting
expedition in the
Solomon
Islands. Theirs is the first frogmouth from
these islands to be caught by scientists in more than 100 years. They
immediately recognized it was something different.
Kratter and Steadman are co-authors to a study analyzing the
frogmouth’s morphology, or physical form, and DNA in comparison to two other
living genera of frogmouths. The findings are published in the April print
edition of Ibis: The International Journal of Avian Science, in a paper that
describes the bird as a new genus and species, now named Rigidipenna
inexpectata.
“This discovery underscores that birds on remote Pacific
islands are still poorly known, scientifically speaking,” Steadman said.
“Without the help of local hunters, we probably would have overlooked the
frogmouth.”
Originally, the bird was misclassified as a subspecies of
the Australian Marbled Frogmouth, Podargus ocellatus. The blunder went
undetected for decades, until a collecting trip led by Kratter in 1998 turned
up a specimen on Isabel, a 1,500-square-mile island in the Solomons. Today, the
only museum specimen of this bird in the world, with an associated skin and
skeleton, is housed at the Florida
Museum.
Frogmouths are predatory birds named for their strikingly
wide, strong beak that resembles a frog’s mouth; but their beak also sports a
small, sharp hook more like an owl’s. Steadman said their beaks are like no
other bird’s in the world. They eat insects, rodents, small birds — and yes,
even frogs.
For perspective on the scale of evolutionary difference
between genera, consider that modern humans and Neanderthals are different
species within the same genus (Homo), while chimpanzees are our living
relatives from a closely related genus (Pan), but that we share the same
taxonomic family (Hominidae) with our chimp cousins.
The Solomon Islands Frogmouth differs from other frogmouths
in a number of significant ways. First, it is probably not as accomplished of a
flier because its eight tail-feathers, instead of the typical 10 to 12 on other
frogmouths, curtail its lift potential, and its much coarser feathers reduce
maneuverability.
“These are island adaptations that work to keep the bird on
the island,” Steadman said.
Second, it has distinct barring on the primary wing feathers
and tail feathers, where other frogmouths are more uniform. Its speckles are
larger, and the white spots on its breast and underbelly are more pronounced
than on other frogmouths.
Two other genera of frogmouths exist: one in southeast Asia
and the other in Australia
and New Guinea.
The Solomon Islands Frogmouth is known to inhabit three islands: Isabel,
Bougainville and Guadalcanal.
Van Remsen, curator of birds at the Louisiana State
University Museum of Natural Science, said that this new frogmouth genus serves
as a poignant reminder that birds of the tropics, particularly from southeast
Asia to Melanesia, have been paid scant
attention by science.
“They’ve barely been studied, much of what we know comes
from antiquated or casual observations,” Remsen said. “The biology of birds in
these regions is, to a great extent, obscured by stale, hand-me-down
classifications from an earlier era. A combination of detailed morphological
and genetic analyses reveal that this frogmouth — formerly dismissed as just a
race of an existing species — actually cannot be placed confidently in any
existing genus, and so the data demand naming a new one.”
Storrs Olson, a senior zoologist with the Smithsonian
Institution, said that frogmouths are an enigmatic group of birds to begin
with.
“That this should prove to be such a distinctive new genus,
which it unquestionably is, has profound biogeographical implications and
represents a real breakthrough in elucidating the evolutionary history of the
family,” Olson said.
Nigel Cleere of the The Natural History Museum in the United Kingdom is the lead author for the paper
and additional co-authors include: Michael Braun and Christopher Huddleston of
the Smithsonian Institution, Christopher Filardi of the University
of Washington’s Burke Museum
and Guy Dutson.
