Making Observations in the Field

"In the field" is a favorite phrase of English-speaking geologists, paleontologists, and some ecologists for referring to their outdoor work, and the same types of scientists in other countries use very similar sayings (e.g., "en el campo" in Spanish). Fossils come out of the earth, so many paleontologists go in the field to search for them. A typical beginning for some paleontological investigations consists of wandering through open countryside, looking at the ground. In dinosaur paleontology, this searching often takes place in deserts or other arid areas lacking appreciable vegetation, although any area containing Upper Triassic-Upper Cretaceous rocks representing terrestrial environments might be examined. This simple methodology has worked well for the past two centuries and probably will not change very much in the near future.

Knowing where to look for fossils, whether of dinosaurs or other organisms, requires some previous knowledge of where they are likely to be found, which means that one should first become familiar with the geology and geography of a prospective field area. For example, if geologists have previously documented rocks only from the Paleozoic Era in an area or they reported rocks that normally do not contain fossils, then the searching for dinosaur fossils will be fruitless. If research shows that some observations of fossils are likely, make sure that the following are taken into account before going into the field:

1 find out who owns the land,

2 get permission to search on the land from whoever owns it, especially if you plan to collect specimens, and

3 learn what is needed to make the field experience a safe and productive one (Chapter 4).

Experience of looking at fossil specimens in a classroom or in a book is no substitute for the real thing when a paleontologist goes into the field, and a field partner who will act as an independent checker of preliminary identifications is invaluable. In this respect, feedback from a field partner is extremely helpful for correcting any mistakes of identification. Identifying any organic-looking rock or feature in a rock as a fossil is a common mistake of inexperienced field practitioners, so skepticism of initial hypotheses should be the norm. For example, paleontologically

FIGURE 2.5 Field occurrence of dinosaur bone, Morrison Formation (Late Jurassic), western Colorado, USA. Notice its fragmentary nature and lack of resemblance to specimens seen in mounted displays of dinosaurs in museums.

FIGURE 2.5 Field occurrence of dinosaur bone, Morrison Formation (Late Jurassic), western Colorado, USA. Notice its fragmentary nature and lack of resemblance to specimens seen in mounted displays of dinosaurs in museums.

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