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Starlings8217; feather tricks for matingIn avian romance, displaying evidence of fitness is the key to finding a mate. Fitness can be demon...

Starlings8217; feather tricks for mating
In avian romance, displaying evidence of fitness is the key to finding a mate. Fitness can be demonstrated in many ways8212;by showing off bright plumage, for example, or by bringing decorative materials to the nest. Most studies of fitness displays have focused on males. But two can play at this mating game. A study by Spanish researchers shows that females of a type of starling decorate their nest with scavenged feathers in a way that is likely to be a signal to potential mates.

The study, by Jose P. Veiga and Vicente Polo of the National Museum of Natural Sciences in Madrid, looked at the behavior of Spotless starlings over three mating seasons. Among these birds, females bring many feathers to the nest, while males rarely do.

The researchers, whose study is published in Biology Letters, counted and identified all the feathers, almost all of which came from four bird species, including Spotless starlings themselves. Most feathers were long ones, only a small percentage were short ones. These long feathers reflect light in visible and ultraviolet portions of the spectrum. They are far more reflective on one side than the other. The researchers found that the female starlings almost always placed the feathers with the more reflective side up. Although they can8217;t say for sure, the researchers say it is likely that the female is using these feathers as a signal of fitness. They may be a sign that the female is in good enough condition or practiced enough in breeding to scavenge for feathers.

Tiny spigot for drugs could be revolution
Scientists at the California Nanosystems Institute at the University of California, Los Angeles, have built a molecular valve that can be opened or shut at will. The valve, described in The Proceedings of the National Academy of Sciences, may eventually be used to control the release of a drug from a tiny implanted device. The valve uses a molecule called rotaxane that can shuttle up and down along a molecular spine by means of a simple chemical reaction. The spine itself is tethered to a tiny cylindrical pore in silica material. When rotaxane is in the down position, it acts like a stopper, plugging the pore opening. When it moves up, the pore opens, so tiny amounts of a drug could be released when the valve is opened.

8212;NYT