Researchers discover ten new bird taxa in Indonesia: An international team of ornithologists has discovered five new species and five new subspecies of songbirds on islands slightly off the northeast coast of Sulawesi.
“From November 2013 to January 2014, we conducted a bird collection expedition to three small and small exploration islands off the northeast coast of Sulawesi, in the current center of Indonesia,” doctor of the Department of Biological Sciences. Frank Rindt said. National University of Singapore and its partners in Singapore and Indonesia.
“These islands are located in the Wallacean region of Indonesia, an archipelago at the interface between Eastern and Australian biographical locations that are named after Alfred R. Wallace, who was the best-known historical collector who discovered the region.”
Using genomic and phenotypic techniques, the researchers described five bird species and five subspecies that are new to science during a 6-week expedition.
In Taliabu, the largest member of the Sula Islands, they found three new species: the Taliabu grass warbler (Locostella portenta), the Taliabu mezomella (Myzomella veh, the Taliabu leaf warbler (Phyloscopus amylsalimi)).
And three new subspecies: the Taliabu eyebrow flycatcher (Fitedula hyperthra betinbiaru), the thrush of the island of Taliabu (Turdus poliocephalus Suahujan), the lulaiiler of the Sula mountain (Fullergetus cuculatus sulanus).
In Peleng, the largest island in the Benghagi group, they found two new species: the Peleng ghost (Ripidura habebei), the Peleng leaf warbler (Phylloscopus suramerdu); And a new subspecies: the Bengai mountain herbivore (Phyllergates cucullatus relictus).
In Bogudaka, one of the two main components of the Togian group, they found a new subspecies: the Togian jungle flytrap (Siornis oasisus omississimus).
Dr. Rindt said: Studying the routes and operations of historical collection expeditions and identifying gaps is a useful approach in our case to indicate focal areas. Describing so many bird species from a geographically limited area is rare.
“It has been reported that most infestations tolerate some form of habitat degradation and are easily found in forests and secondary coasts, these species or subspecies cause habitat loss on these islands,” he said. Undoubtedly there is danger of large scale. ”
As such, some of the new forms require immediate and lasting conservation action to survive for more than a few decades beyond the date of description. These new bird taxa are described in an article published in the journal Science.
Called Megabitochondria-Small Oil Droplet Complex (MMOD Complex), this structure can allow these birds to sit and wait to see their world differently from other animals, and find pests and easily track them. Help to do.
This light microscopy image of the Acadian Flycatcher (Empedonax Wierskens) retina shows five drops of conventional oil and additional orange conical structures belonging to the newly described photoreceptor.
Most birds have four cone photoreceptors for color vision, a fifth cone for non-color related functions and a night vision rod.
Each cone photoreceptor cell has a spherical structure, called an oil drop, that filters the light before the visible pigment converts it into electrical signals, which increases color discrimination.
Instead of a drop of oil, the MMOD complex, which is found in two species of new world fly hunters of the genus Empedonax (E. virescens and E. minimus), has a high-energy cellular structure called megamecondria that Surrounded by hundreds of small orange colors – Individual drops.
“We discovered that Empedonax’s flycatchers, like all birds, had four single-cone photoreceptors, each with a drop of spherical oil in the inner section of the photoreceptor,” said lead author Professor Estebai Fernández-Juric. Department of Biological Sciences of Purdue University.
Like other birds, the dominant member of the Empidonax double cone also has a drop of spherical oil. Each type of cone contained droplets of oil of a different color that could be easily observed with a simple optical microscopy. “
“In addition to these five conventional cones and their associated oil droplets, we found that Empidonax is in the Flycatcher retina, which is probably an additional cone photoreceptor with a novel orange conical structure at the apical end of the inner segment.”
The photoreceptors with this organelle lacked a drop of oil that is present in other types of cone. Image of transmission electron microscopy of oranges, conical structures reveal that they are megamitochondria dense in electrons surrounded by numerous small drops of oil.
The white asterisk denotes megamitochondria, the orange arrow indicates the small drops of oil that impart the orange color seen in the image above, and the blue arrow indicates a drop of conventional oil from the neighboring photoreceptor.
The researchers studied the MMOD complex using light microscopy, transmission electron microscopy and microspectrophotometry.
They discovered that this structure acted as a long-pass filter, allowing light with wavelengths to pass 565 nm long, or yellow, orange and red, and absorb shorter wavelengths of green, blue and violet. It is.
“The retinas of fly hunters, which are predatory birds sitting on hold, have developed a new cellular structure in a photoreceptor that allows them to detect, track and capture prey that grows rapidly like insects,” said the professor. Fernández-Jurisic said.
A researcher from the Department of Biological Sciences, Dr. Luke Tyrell said: “This new conical organism has not been described before in any other vertebrate retina and these birds can see their world differently from other animals.” In SUNY Plattsburgh.