Finding a fossilized shark tooth can be an exciting discovery, offering a tangible link to ancient marine life. Identifying a shark tooth requires recognizing specific physical characteristics that distinguish them from other natural objects. This guide will help you discern genuine shark teeth from common look-alikes.
Distinctive Features of Shark Teeth
Shark teeth possess unique characteristics that distinguish them from other natural finds. Their overall form can vary significantly depending on the shark species and its diet. Many predatory sharks, like the extinct Megalodon and modern great white sharks, have broad, triangular teeth for cutting and tearing prey. Other species, such as mako sharks, feature long, slender, and pointed teeth for grasping fish. Some teeth can also be blade-like or conical.
Many shark teeth exhibit serrations, which are small, saw-like edges along the blade. While present in species like the tiger shark or great white, not all shark teeth are serrated. For instance, mako shark teeth are typically smooth-edged. The presence or absence of these serrations is an important identification marker.
A shark tooth’s root structure is another key indicator. The root, which anchored the tooth in the shark’s jaw, is often bilobed or flattened. It is distinct from the crown, the visible part of the tooth, and typically shows a clear separation. Some roots can be thick and U-shaped, while others might be more square-shaped.
The crown of a genuine shark tooth has a smooth, often glossy texture due to its enameloid composition. This hard, mineralized material covers the dentin. A bourlette, a raised band located between the crown and the root, is also present on some teeth, notably those from Megalodon. This combination of shape, edge features, root morphology, and enamel texture provides reliable clues for identification.
Common Items Mistaken for Shark Teeth
Many natural objects found on beaches or riverbeds can resemble shark teeth, leading to misidentification. Rocks and pebbles are frequently confused with teeth due to their similar size and color. However, rocks generally lack the distinct anatomical features of a tooth, such such as a defined crown and root. They also tend to have a different texture compared to the smooth, hard enameloid of a shark tooth.
Shell fragments also pose a common challenge for identification. While some shell pieces might have a triangular outline, they typically exhibit layered structures or iridescent qualities not found in shark teeth. Unlike the glossy, solid surface of a tooth, shell fragments often have ripples or a chalkier texture.
Other animal bones or teeth can be mistaken for shark teeth, but their structure differs significantly. Shark teeth uniquely develop outside the jaw bone and have a distinct root separate from the crown, unlike most mammalian teeth. These other animal remains lack the characteristic shape and enameloid surface of a shark tooth. Man-made debris, such as glass or plastic, may share a similar color or shape but lack organic structure or the feel of a fossilized tooth.
Understanding Shark Tooth Variations
Shark teeth exhibit a wide range of appearances, even among genuine specimens. Their color is variable and depends on the fossilization process and the minerals present in the surrounding sediment. Common colors include black, gray, brown, and tan, but they can also be red, blue, or green. This coloration results from minerals seeping into the tooth, replacing its original organic material. Modern shark teeth, in contrast, are typically white.
The size of shark teeth varies, ranging from less than half an inch to several inches long. This variation is influenced by the shark species and its specific diet. The position of the tooth within the shark’s jaw also affects its size and shape, as does the age and sex of the individual shark.
Natural wear and tear can also alter a shark tooth’s appearance. Teeth can show signs of damage from feeding, such as chipped tips or serrations. Weathering and erosion during the fossilization process can cause cracks or pits on the surface. These imperfections do not negate a tooth’s authenticity but reflect its long journey from a living shark to a fossilized find.