Worldwide, there are only a few dozen places with rocks that could potentially contain such remains. Here in the populated eastern seaboard of the United States, most of the rock formations from the Triassic are covered by buildings, parking lots or dense vegetation. Sites for prospecting are largely restricted to roadcuts, construction sites and quarries. An important site in central Virginia that I excavated many years ago is now buried beneath a school football field.
There, you can collect lots of fossils without having to worry about being obliterated by vehicles passing inches away. Looking for fossils takes patience and perseverance. Sometimes you spend days or weeks in the field before finally making an interesting find. I have collected fossils of Triassic vertebrates along the shores of the Bay of Fundy in eastern Canada, where on average, I find only three or four pieces of bone per mile of shoreline.
Most of these are so incomplete it is impossible to tell what bone they are, much less which animal they came from. Even so, over the many years searching the area, other collectors and I have assembled a sizeable collection of fossils—many of them species new to science. Some collectors have a real knack for finding fossils even where they are rare.
Others bring great enthusiasm but will literally step on fossils without seeing or recognizing them. Success heavily depends on quickly learning how to distinguish fossils in a particular type of rock. When I first started collecting along the shores of the Bay of Fundy it took some time before I was able to tell cross-sections of white bones on surfaces of red sandstone from similar-looking mineral inclusions and bird droppings. My tool kit for fossil hunting contains rock hammers, chisels, protective glasses, a loupe, my notebook, various kinds of glue, and packing material and crates.
Before visiting a place with exposures of rocks that I want to study, I am careful to obtain permission from the land owner. Unless collecting is done merely for mementos, it is extremely important to record details about the fossil sites and their exact location.
When first uncovered, fossils are often fragile and must be stabilized with glue. Then each find is carefully wrapped and labeled before being taken to a lab or to the museum. Straight lines that end in holes are evidence of bones, revealing the fossilized Haversian canals. If the lines on one edge are perpendicular to the lines on the adjacent surface—this is merely a mineral.
Fractured stones have lines that go in many directions. Lick one of the ends with holes, wetting it with saliva, then press it into your finger, hold it firm, and count to ten. Bona fide dinosaur bones will stick to your finger so that even if you shake your hand, the bone will stay stuck. The stick test works from capillary action in the hollow tubes of the dinosaur bone, causing suction.
Dry bones stick better than wet ones, and small bones work better than big ones, whose canals often get filled in with sediment. Now you have to find out where they come from. Float mapping is a study in erosion and taphonomy decay. Digging is done with a variety of tools, from small brushes and ice picks to giant pickaxes and even mechanical backhoes.
Still, paleontologists are meticulous, cautiously removing dirt and stone, recording everything that transpires. Paleontologists might spend more time documenting a dig than they spend actually digging. In Montana, they mark a datum point and use GPS to record the exact locations of each find, no matter how small. Once they find bone, they work gently around it, knowing that it might be connected to other bones, or perhaps if they are lucky a whole skeleton. Paleontologists are detectives, working every day to solve a mystery.
On my dinosaur dig, I spent most of the afternoon chiseling away at grey sandstone, slowly removing the sediments around a very large dinosaur bone, crumbling away the non-essential dirt but always conscious that there might be something bigger and better in there. Sure enough, we found another hard surface and discovered a much larger bone hidden beneath the sandstone. Suddenly I understood the compulsion of paleontologists and all the millions of children that are in love with dinosaurs.
Visitors to Two Medicine Dinosaur Center in Bynum, Montana can participate in 3-hour, full-day, or longer-term dig programs, which can cater to serious paleontology students or for children and families. All rights reserved. I also learned the seven fundamental steps behind finding dinosaur bones: 1. These crates help protect the fossils from breaking.
The crates are carefully loaded onto trucks and sent to the lab. There, scientists will use the fossils to learn about creatures of long ago. Do you think it is important for us to study animals that lived long ago? Why or why not? Guide students through their study of dinosaurs with these articles, lesson plans, online learning activities, and writing assignments. Create a List. List Name Save. Rename this List. Rename this list. List Name Delete from selected List. Save to. Save to:.
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