DBS Recent Publications

How did birds take to the air? In a recent Nature paper Ken Dial and students Brandon Jackson and Paolo Segre propose a new hypothesis. Using common, ground-dwelling chukars , they analyzed how birds flap their wings across a juvenile-to-adult developmental sequence. Although birds at different stages used their wings very differently—early stages used them to assist running up inclines while adults used them for different kinds of flight—the wing stroke angle was remarkably conserved. Dial and colleagues argue that this conservation represents a fundamental bird wing stroke, which appears very early in development and can be used for a variety of purposes.

The authors then connect their developmental data to evolutionary origins of flight. In particular, they suggest that transitional stages during the evolution of flight correspond to the developmental sequence observed in chukars. In particular, proto-birds may have flapped their proto-wings, using the fundamental avian wing stroke—to flap-run over obstacles and control how they fell. Ultimately, these non-flying but aerodynamically-useful wings evolved into structure capable of performing level, flapping flight.

Graduate student Marnie Rout & her advisor Ray Callaway publish a perspective in Science on paradoxical ecosystem alterations in invaded systems due to microbial interactions with invasive plants. The paper discusses the "invasion-diversity-productivity" paradox, in which invaded systems show changes in ecosystem functions, particularly in nitrogen cycling.