Rewriting the Family Tree: In a development made possible only with the latest techniques in DNA sequencing, researchers at the Smithsonian Conservation Biology Institute’s Center for Conservation and Evolutionary Genetics have tracked down the ancestor of Hawaiian honeycreepers, those birds that present such an amazing example of adaptive radiation.
And the result?
The Hawaiian birds trace back to a Eurasian rosefinch – and not, as had been widely thought, a North American or European finch.
Authors Heather Lerner, Matthias Meyer, Helen James, Michael Hofreiter, and Robert Fleischer published their findings in Current Biology. Their conclusions were based on analysis of mitochondrial DNA from 47 bird taxa, including 19 honeycreepers that still exist or are recently extinct.
The ancestral colonists arrived in the Hawaiian islands sometime between 7.2 million years ago (mya) and 5.8 mya, but not until a couple of million years later, with the emergence of O`ahu, did adaptive radiation really take off. This “burst” occurred, the authors wrote, during “a time period that encompasses the formation of O`ahu, yet precedes the formation of Maui Nui.” Six of 10 major “morphological lineages” evolved during this time frame, while only two evolved after. This, they write, “emphasizes the importance of the formation of O`ahu, more so than Maui Nui, to the present-day morphological diversity of Hawaiian honeycreepers…. O`ahu, as a newly formed island initially without avian residents, likely provided a blank slate allowing ecological and morphological differentiation.”
As to the mechanism by which the initial colonizers arrived, the authors note that rosefinches “often move in large mixed-sex groups to new wintering grounds” in a behavior called “irruption.” “It is possible that colonization by the ancestral species was aided by the arrival of a large mixed-sex flock in the islands, representing a sizable gene pool. Thus, a diverse initial gene pool may have facilitated speciation and the evolution of extreme morphological diversity in the honeycreeper radiation.”
Earthstars in Hawai`i: Some of the prettiest plants in Hawai`i are also among the most obscure. In the fall 2011 edition of Pacific Science, Don Hemmes, recently retired from the University of Hawai`i at Hilo Department of Biology, and Dennis Desjardin, of the Biology Department at San Francisco State University, describe the results of surveys over the last 15 years that looked for earthstars – tiny fungi that produce spores within a shell that splits open to release them, forming star-like patterns.
Their article, “Earthstars (Gaestrum, Myriostoma) of the Hawaiian Islands Including Two New Species…” describes the 17 previously known species and adds descriptions of two more.
If you want to find some on your own, the best months to do so are from September through February, typically the wetter months in Hawai`i. Look in the duff under ironwood trees along coasts, in the koa haole thickets above Lanikai, in the dry kiawe groves at Puako, or at higher elevations, including the `ohi`a-koa forests at Koke`e on Kaua`i, or even in forested kipukas along the Saddle Road of the Big Island.
NELHA Tries Again on OTEC: The board of directors of the Natural Energy Laboratory of Hawai`i Authority has approved the proposal of a company based in Baltimore to develop an ocean-thermal energy conversion plant at the NELHA facility near the Kona-Keahole airport. The company, OTEC International (OTI), LLC, was one of four to respond to a request for information put out by NELHA in September.
In reviews by NELHA staff as well as the NELHA board’s research advisory committee, OTI received top scores. But certain issues still need to be ironed out before the company gets the final go-ahead. At the board’s meeting last month, NELHA executive director Greg Barbour described how the demand for deep seawater by the OTEC plant may not be met without shorting existing NELHA tenants who use the water for everything from abalone aquaculture to desalinated bottled water products.
“The next step is for us to begin negotiations immediately,” Barbour said. “We would like to come back to the board with more detailed findings and hopefully a proposal … at the next board meeting,” scheduled for January.
OTI is already in negotiations with Hawaiian Electric for a power purchase agreement to cover production from an offshore 100-megawatt OTEC plant proposed near Kahe Point, O`ahu.
According to Barry Cole, executive vice president of OTI, the NELHA plant will be a demonstration plant “to reduce risk for its first full-scale commercial project.” Still, he said, it is still intended to produce more power than it consumes.
OTI is a project of the Baltimore-based Abell Foundation, which allocates a portion of its investment portfolio to “innovative technologies and early-stage companies that have exceptional social, environmental, and economic return potential, including energy efficiency and alternate energy,” according to a foundation fact sheet.
Volume 22, Number 6 — December 2011