User:Mz7/sandbox/Feathers

Content summary

Following a preface and introduction, Feathers is divided into five main parts: "Evolution" discusses the evolutionary history of feathers, "Fluff" explains the role of feathers in regulating body temperature, "Flight" discusses the origin of avian flight as well as its impact on human aviation, "Fancy" discusses the role of feathers in sexual selection and human fashion, and "Function" discusses the continuing evolution of feathers in both nature and human usage.

Evolution

Feathers begins with the 1861 discovery of the first Archaeopteryx fossil specimen, and the resulting debate between English paleontologist Richard Owen, an opponent to evolution by natural selection, and Thomas Henry Huxley, an advocate for evolution. Hanson himself visits the Wyoming Dinosaur Center, a small museum in Thermopolis, Wyoming, which had acquired an Archaeopteryx specimen. Hanson interviews Richard Prum, the Coe Professor of Ornithology at Yale University, who proposed a developmental theory of feather evolution, which focuses "on how feathers grow and not worrying about what they're used for.". Hanson also interviews Alan Feduccia, a professor at the University of North Carolina, who disagrees with the scientific consensus that birds evolved from theropod dinosaurs. Later, Hanson interviews Xing Xu, a Chinese paleontologist who described fossil specimens that helped support Prum's developmental theory, such as Beipiaosaurus and Microraptor. Hanson also discusses the development of feathers in thin-billed prions, as well as how feather growth is controlled by the Sonic hedgehog gene.

Fluff

In "Fluff", Hanson describes his experience at Winter Ecology, a "hands-on exploration of cold-weather ecosystems" organized by Bernd Heinrich, a biologist at the University of Vermont. While staying in a log cabin in a remote location in western Maine, Hanson observed how golden-crowned kinglets and other birds were able to keep warm on nights when the temperature was −17 °F (−27 °C) and discusses the role of feathers in maintaining a comfortable body temperature for birds. To understand how down feathers have been adapted for human purposes, Hanson interviews Travis Stier at the Pacific Coast Feather Company, which manufactures pillows and comforters made with feathers. Later, Hanson discusses various strategies that birds employ to keep cool in warmer climates and during periods of muscular activity, such as flight and fast running, as well as the role of feathers in these strategies.

Flight

Scientists disagree on how feathered flight originally evolved, and Hanson describes various viewpoints on the subject. The "ground-up" view holds that flight originated from theropod dinosaurs running along the ground, whereas the "tree-down" view holds that flight originated from animals who lived in trees "as a means to extend their hops from branch to branch". Hanson discusses the issue with Feduccia, who argues for the "tree-down" view, noting that other vertebrates also developed flight from the tree down. Hanson also discusses with Prum and Xu, who state that while the origin of feathers might have been ground-based theropods, the origin of flight could have been theropods who climbed trees, especially considering four-winged feathered theropods like Microraptor. Hanson interviews Ken Dial, an ornithologist who described wing-assisted incline running (WAIR), a behavior exhibited by baby birds learning how to fly. WAIR has been proposed as an alternative model for the origin of avian flight, as it addresses weaknesses in both the "ground-up" and "tree-down" views. Later, Hanson interviews Ken Franklin, who raised Frightful, a peregrine falcon whose dive was measured to be 242 miles per hour (389 km/h), making her the fastest flying animal on record. Franklin describes the role of feathers in improving the aerodynamics of a falcon's flight. Hanson concludes the "Flight" section with discussion of how feathered flight has influenced human aviation.

Fancy

Hanson describes the behavior of birds-of-paradise and the role of their elaborate feathers in sexual selection. Hanson also visits the Las Vegas Strip and observes how feathers play a role in pageant shows like Jubilee!. Hanson interviews Marios Ignadiou, the head of Jubilee!'s costume shop, as well as fashion designer Pete Menefree. Hanson then describes the history of the feather trade in fashion. In the period before World War I, feathers were highly valuable commodities. Wanting to capitalize on the economic strength of feathers, the government of South Africa sponsored the Trans-Saharan Ostrich Expedition, led by Russel William Thornton to find the Barbary ostrich. After much adversity, Thornton and his crew returned to South Africa in 1912 with 127 surviving Barbary ostriches. Unfortunately, demand for feathers in fashion decreased dramatically a few years later, once more women entered the workforce for the war effort. Hanson later interviews Leah Chalfen, a hat designer based in New York City who specializes in feathers. Hanson also interviews Jodi Favazzo, the owner of the Rainbow Feather Company, which dyes feathers.

Function

Hanson rescues a grounded common murre by carrying it back to the ocean (takeoff is extremely difficult for murres if they are not on water). He then explains how the structure of feathers is waterproofing, keeping birds dry in wet conditions. Hanson interviews John Sullivan, an experienced fly fisher who explains the role of feathers in fly fishing. Later, Hanson explains the history and use of feathers in quill pens, which he uses as an example of how feathers have been adapted for other purposes beyond their natural evolutionary purposes. Hanson also describes his experience observing the behavior of vultures in Kenya, in which he discusses the lack of feathers on the heads of vultures. Hanson interviews Kimberly Bostwick, an ornithologist and curator at Cornell University Museum of Vertebrates, who discusses her research in the club-winged manakin, a bird whose feathers enable it to make sounds with its wings. In the National Museum of Natural History, Hanson interviews Carla Dove, who works in the museum's Feather Identification Lab, which identifies the species of bird which a feather originates from.