Avian song learning is an important model system for understanding vocal learning in humans and other animals. Laboratory studies indicate that social interactions are critical for song learning, but field observations show that territorial males are aggressive to intruders, raising the question of whether young birds are tolerated, much less tutored in the wild. We examined how adult song spar...

The atmospheric Ar/N2 ratio is expected to be useful as a tracer of air-sea heat exchange, but this application has been hindered in part due to sampling artifacts. Here we show that the variability in δ(Ar/N2) due to thermal fractionation at the inlet can be on the order of 40–80 per meg, and we introduce the use of an aspirated solar shield that successfully minimizes such fractionation. The ...

Editor's Note: It seems appropriate, in this issue of JSS containing the ®ndings of our annual Top Scholars/Institutions study, to pay tribute to the persistent authors who make a journal like this, and a study like that, possible. In their honor, we dedicate the following humorous, anonymously-authored, letter! Dear Sir, Madame, or Other: Enclosed is our latest version of Ms. #1996-02-22-RRRRR...

Tissue and organ viability depends on the proper systemic distribution of cells, nutrients, and oxygen through blood vessel networks. These networks arise in part via angiogenic sprouting. Vessel sprouting involves the precise coordination of several endothelial cell processes including cell-cell communication, cell migration, and proliferation. In this review, we discuss zebrafish and mammalia...

Earnings nonresponse is currently about 30% in the CPS-ORG and 20% in the March CPS. Census imputes missing earnings by assigning nonrespondents the reported earnings of matched donors. Even if nonresponse is random, in a wage equation there exists severe “match bias” on coefficients attached to non-match imputation attributes (union status, industry, foreign-born, etc.) and imperfectly matched...