AREAS OF FORENSIC SCIENCE
The areas of forensic science covered in this textbook are listed in the table of contents by chapter. They can be broadly characterized into chemical, biological, and physical sciences. Some areas may overlap (aren’t fingerprints, tool marks and shoeprints all impression evidence?) but this text focuses on their original source or production method to organize the topics to make the most sense. Many kinds of scientists may be called upon to play a role in a forensic investigation. This does not mean, however, that this is their full-time job: their area of expertise may need to be called upon only rarely or only in particular cases. Artists, biologists, chemists, and other specialists may be needed to answer questions in investigations as diverse as mass disasters, aero plane crashes, missing persons, and art forgeries (see “In More Detail: Birds of a Forensic Feather”).
IN MORE DETAIL: BIRDS OF A FORENSIC FEATHER When US Airways Flight 1549 made its amazing crash landing in the Hudson River in 2009, probably the last thing on anyone’s mind was the word “snarge.” The word may sound funny, but “snarge” is the technical term for the pulverized bird guts resulting from the collision of an aero plane and a bird. Dr Carla Dove, at the Smithsonian Institution’s Museum of Natural History in Washington, DC, is the Director of the Feather Identification Laboratory, where thousands of bird samples are sent each year for identification, most of them involving bird strikes with aeroplanes. Forensic feather identification is important not only to determine the cause of a crash but also to potentially help rule out other types of causes, such as mechanical issues or terrorist activities. The feathers or other bird parts are examined and compared with the laboratory’s extensive reference collection (over 620,000 samples, some collected by Theodore Roosevelt and possibly Charles Darwin, representing 85% of the world’s bird species) to deter mine the bird’s species (see Figure 1.1). If that does not work, the snarge is sent to the DNA laboratory
FIGURE 1.1 The anatomy of a feather. (1) Vane; (2) Rachis; (3) Barb; (4) Afterfeather; (5) Hollow shaft, calamus.
