Research Results
Approximately 60 1-gallon buckets of beach sediments were collected at each of the study sites. These samples were screen washed and all shark teeth were collected and identified to genus.
| Shark Name | Genus | Total Bay % | Brownies' % | Scientists' % | Matoaka % |
| Requiem | Carcharhinus; Negaprion | 47% | 66% | 68% | 73% |
| Hammerhead | Sphyma | 1% | 1% | 2% | 1% |
| Snaggletooth | Hemipristis | 15% | 2% | 4% | 4% |
| Sand Tiger | Carcharias | 5% | 13% | 2% | 1% |
| Tiger | Galeocerdo | 20% | 3% | 4% | 7% |
| Mako | Isurus | 4% | 0% | 2% | 1% |
| Angel | Squatina | 1% | 1% | 1% | 1% |
| Thresher | Alopias | 1% | 0% | 0% | 0% |
| Giant White | Carcharodon | 3% | 0% | 0% | 0% |
| Cow | Notorynchus | 1% | 1% | 0% | 0% |
| Sharpnose | Rhizoprionodon | Unknown | 2% | 2% | 0% |
| Unknown Teeth | Unknown | 7% | 11% | 4% | |
| Ray Dental Plates | Aetobatus; Myliobatis | Unknown | 4% | 5% | 10% |
| Total Teeth Found | Unknown | 575 | 144 | 163 | |
| Percentages are rounded and do not always add up to 100%. | |||||
| Total Teeth Found | includes Ray Dental Plates. | ||||
| Requiem includes the Lemon and Gray shark. | |||||
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In conclusion from our studies, we can suppose that the number of shark teeth found is based on the time and climate it lived in. For example the Requiem shark – this includes the Lemon and Gray shark – is the most common shark because of the many fossilized teeth that are collected. Knowing this we can infer that the environment during the time that the Requiem sharks of the Miocene epoch lived in included possibly warm, shallow waters and a near shore milieu. The environment of the sharks can be assumed because “The present is the key to the past.” This means that what we know about a shark’s environment today can be used to learn about sharks from the past. Believing this we can say that since present day Snaggletooth sharks live in a near shore environment, it is possible to think that past day Snaggletooth sharks lived in a similar setting. Based on the data of our collected shark teeth, we can guess that the Sand Tiger from the Calvert formation at Brownies Beach, which is the oldest zone from which we collected, lived in a cooler water environment than the beaches that existed at Scientists Cliffs and Matoaka Cabins, which are beaches in a younger time zone. We know this because at Brownies Beach 13% of the shark teeth we found came from the Sand Tiger. At the two other sites, they were only an average of 1.5% of our colleted teeth. Using information of the world we live in today can help us better understand the past.
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The Paleontological Research
Institution |