art in science

Bird-plant symbiosis. The Metrosideros, or ohi'a in the Hawaiian language, is one of the dominant plants in Hawaii. It has a symbiotic relationship with many of the Hawaiian birds including the apapene. The apapane pollinates the flower as it feeds on nectar. Although it was once thought a relative newcomer to Hawaii, research by scientists at the National Museum of Natural History and the Smithsonian's National Zoo show that the plant flowered on Hawaii soon after the islands appeared out of the ocean.

Photo: Jack Jeffrey

Save me. More than 2,300 species including the giant leaf-tailed gecko, 7 to 10 inches long, are found in the wild on the island of Madagascar, off the east coast of Africa, and nowhere else in the world. In a new conservation plan introduced in the journal Science, conservation biologists map out the locations for thousands of animal and plant species on Madagascar, to find the most important habitats to preserve. That contrasts with the usual efforts, which focus on a few high-profile and popular animals.

Photo: Piotr Naskrecki

A deep dissection of the side of the head shows the many blood vessels (red arteries, blue veins) and nerves (graying white) in the facial region. The hole is the external ear canal. The temporal muscle, used for chewing, is the prominent fan shaped muscle on the side of skull, behind the mouth and above the jaw.

Photo: William B. Gruber

After the removal of an outer layer of bones around the jaw, the dissection shows blood vessels and sensory nerves to the lower teeth and chin. The process was slow, in part because the Kodachrome film had to be sent to Kodak in Rochester, N.Y., to be developed. Mr. Gruber had to check that the photos came out satisfactorily before Dr. Basset could proceed with his dissection.

Photo: William B. Gruber

Individually Marked Ants
Stephen Pratt
Department of Ecology and Evolutionary Biology

THIRD PRIZE WINNER

Ant colonies show remarkably coordinated behavior, despite lacking any direction from a well-informed central controller. Each worker instead applies simple decision rules to limited knowledge, and exchanges information with her neighbors using rudimentary cues and signals. From this process emerge the construction of complex nests, collective decisions among food sources, the adaptive allocation of labor across tasks, and many other group accomplishments. To identify the underlying decision rules requires a detailed description of the behavior of individually identifiable ants. The ant species Temnothorax curvispinosus is especially useful for this kind of study, because they form small colonies of only a few hundred workers, and they thrive in thin, glass-walled laboratory nests, facilitating detailed video records of their behavior. Most importantly, as shown in these images, workers can be individually marked with tiny drops of paint. Ants are first immobilized with carbon dioxide, and then marked with a distinctive pattern of four drops. They soon emerge unharmed from narcosis, and retain their marks for several months to years. This approach has been particularly useful in showing how emigrating colonies can choose the best among several new homes, even when few individual workers are aware of all the options under consideration.

Dynamic Asset Allocation in Freight Transportation
Warren B. Powell and Belgacem Bouzaiene-Ayari
Department of Operations Research and Financial Engineering

This graphic comes from a dynamic asset allocation problem in railroads. The system, which is now in production at Norfolk Southern railroad, is the first production implementation of a stochastic, dynamic programming model in freight transportation. The model is based on the Ph.D. dissertation of Huseyin Topaloglu (now a professor at Cornell University) for stochastic, integer multicommodity flow problems. The original research was modified to handle multidimensional attribute problems, with millions of asset types.

Driven
Anton Darhuber, Benjamin Fischer and Sandra Troian
Microfluidic Research and Engineering Laboratory, Department of Chemical Engineering

SECOND PRIZE WINNER

This image illustrates evolving dynamical patterns formed during the spreading of a surface-active substance (surfactant) over a thin liquid film on a silicon wafer. After spin-coating of glycerol, small droplets of oleic acid were deposited. The usually slow spreading process was highly accelerated by the surface tension imbalance that triggered a cascade of hydrodynamic instabilities. Such surface-tension driven flow phenomena are believed to be important for the self-cleaning mechanism of the lung as well as pulmonary drug delivery.

Strange Crystal
Darsh Ranjan '05
Department of Mathematics

This crystal grows on its black substrate from a pentagonal seed by reflecting it across its 5 vertices and rescaling the new pentagons by a factor of 0.61803..., the “golden mean,” back towards the point of reflection, and repeating this for all the new pentagons, ad infinitum. Each seed can have its own rule to determine its color and the colors of its descendants. The growth of a single seed has finite area but infinite detail (possessing a fractal dimension of 2). This crystal is strange because crystals in nature do not possess 5-fold symmetry on any large scale, while this one can fill the entire plane very nicely with appropriately placed seeds. In understanding this shape, the arithmetic of the integers extended by the fifth roots of unity proves very helpful.

Wake of a Pitching Plate
James Buchholz GS and Alexander Smits
Department of Mechanical and Aerospace Engineering

These images contain top and side views of the wake produced by a rigid plate pitching about its leading edge in a uniform flow (flowing left to right). The leading edge of the plate is hinged to the trailing edge of a stationary symmetric airfoil. The wake is visualized using fluorescent dyes that are introduced through a series of holes on each side of the airfoil support. Twice in each flapping cycle, a horseshoe-shaped vortex is shed from the top, bottom, and trailing edges. The vortices become entangled to form the chain-like structure shown here. Studying such wakes is believed to be important for understanding the mechanisms of thrust production in fish-like swimming.

Seahorse Anatomy
Elina Mer
Spouse of a Graduate Student

This image was created in Photoshop to illustrate the vertebral column of the genus Hippocampus. While most fish have scales, seahorses have bony plates over which a thin layer of skin is stretched. Seahorses are vertebrates and thus have a vertebral column that runs through the center of their body and the center of their prehensile tail.

Five-Horned Eggshell
Nir Yakoby and Maria Pia Rossi
Department of Chemical Engineering

This image is a scanning electron micrograph of the anterior portion of a Drosophila virilis eggshell. At this high resolution, its microscopic features can be seen in striking detail. The most obvious structures are the four respiratory appendages (green) that help the fly developing inside the eggshell to breathe. The fifth, shorter “horn” is the micropyle, which is a small tube used for sperm entry. Also of interest, the complex web-like pattern of white proteinaceous material indicates the outline of the individual cells that secreted the eggshell.