Mako Shark Facts, Evolution, Fossil Teeth, and Identification Guide

Learn about mako sharks (Isurus), including the Shortfin and Longfin Mako, their evolution, fossil teeth, tooth identification, size, speed, diet, and fossil occurrences from the Paleocene to today. This guide explores modern mako sharks, extinct fossil species, and how to identify fossil mako shark teeth from locations such as Calvert Cliffs, Aurora, and other famous fossil sites.

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Mako Shark Facts - The Isurus Genus - The Details

Mako sharks belong to the genus Isurus, a group of fast-swimming pelagic sharks in the family Lamnidae. They are closely related to other highly adapted open-ocean predators and are known for their speed, streamlined bodies, and powerful swimming ability.

Types of Mako Sharks: There are two living species today: the shortfin mako (Isurus oxyrinchus) and the longfin mako (Isurus paucus). The shortfin mako is more common and widely distributed, while the longfin mako is rarer and less frequently encountered.

Range, Diet, and Size: Mako sharks are found in temperate and tropical oceans worldwide. They are pelagic hunters that feed mainly on fish such as tuna and mackerel, along with squid and occasionally other sharks. Shortfin makos typically reach about 10 feet (3.2 m), though larger individuals are known. They are among the fastest sharks, capable of bursts exceeding 30 mph.

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Mako Shark Evolution - General Overview

Mako shark evolution is based primarily on isolated fossil teeth, which makes the evolutionary history complex and still actively studied. What is known comes from comparing tooth morphology across multiple fossil lineages of lamnid sharks.

Paleocene origins: The earliest mako-like sharks appear in the fossil record as Isurolamna during the Paleocene, approximately 60 million years ago. These early forms represent some of the earliest members of the lamnid shark lineage.

Eocene diversification: By the Eocene, mako-like sharks such as Macrorhizodus appear. These sharks show transitional features and are often discussed in relation to the early evolution of both mako sharks and the lineage leading toward white sharks.

Link to white sharks: Some fossil lineages related to early makos later evolve broader, more serrated teeth and are associated with the evolutionary pathway toward white sharks, including Cosmopolitodus and Carcharodon.

Modern makos: By the late Oligocene and Miocene, modern-type mako sharks appear. At least two species are recognized in the fossil record and persist into the present:

Shortfin mako: Isurus oxyrinchus (also historically referred to as I. desori)

Longfin mako: Isurus paucus (also associated with I. retroflexus)

Related forms and ongoing debate: One unusual fossil shark historically referred to as Isurus escheri is often called the "serrated mako" because its teeth combine mako-like features with serrated cutting edges similar to white sharks. More recent research has suggested this species may represent a transitional lamnid shark closely related to the lineage leading to modern white sharks rather than a true member of the mako shark genus Isurus. As a result, many researchers have placed it in the genus Carcharon. However, the evolutionary relationships among these early lamnid sharks are still debated, and research on mako and white shark ancestry continues to evolve.

Overall, mako shark evolution remains an active area of research, and some fossil species are still debated in terms of classification and evolutionary relationships.

Special thanks to Bill Heim for contributions and fossil material used in this section.

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Shortfin Mako Shark Tooth Morphology and Identification

Many fossil shark teeth commonly referred to as "mako shark teeth" by amateur collectors are actually extinct white shark relatives. Broad, triangular teeth sometimes with serrated cutting edges usually belong to extinct white sharks in the Carcharodon genus, not true mako sharks. If you are looking for identification help for those teeth, visit the Prehistoric White Shark Page.

The modern Shortfin Mako shark, Isurus oxyrinchus, produces the classic narrow, spear-shaped teeth most commonly associated with fossil mako sharks. Some researchers believe the extinct species Isurus desori may actually represent the same lineage as the living Shortfin Mako. As a result, some paleontologists consider I. desori and I. oxyrinchus to be synonymous.

Fossil teeth of Isurus oxyrinchus are also extremely similar to those of the living Longfin Mako, Isurus paucus. It is still debated whether certain fossil mako tooth forms belong to I. paucus rather than I. oxyrinchus. If the two species can be reliably separated in the fossil record, the differences appear to be very subtle and are beyond the scope of this page.

Upper teeth of Isurus oxyrinchus typically have long, slender crowns adapted for grasping fast-moving fish prey. In the anterior portion of the jaw, the roots are elongated and narrow, while the lateral teeth develop broader crowns and more squared root lobes. Upper lateral teeth are generally broader than the upper anterior teeth.

Lower teeth also have long, slender crowns, but they usually display a slight lingual bend toward the inside of the mouth. Unlike the upper teeth, the lower lateral teeth tend to remain narrow and peg-like rather than becoming broader.

Because mako shark teeth are smooth-edged, narrow, and highly streamlined, they are well adapted for capturing slippery prey such as fish and squid. Their tooth morphology reflects the mako shark's role as one of the fastest predatory sharks in the open ocean.

Below are two diagrams illustrating the morphology of an upper anterior tooth and a lower anterior tooth of Isurus oxyrinchus.

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High Quality Shark Teeth by Fossilera

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Examples of Mako Shark Fossils

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Isurus oxyrinchus aka Isurus desori
Shortfin Mako Shark

Isurus oxyrinchus teeth are very similar to the fossil I. desori teeth. Many believe it should be assigned to the same species.

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Reference

Jurgen Kriwet, Heike Mewis, and Oliver Hampe. (2015) A partial skeleton of a new lamniform mackerel shark from the Miocene of Europe. Acta Palaeontologica Polonica 60 (4), 2015: 857-875 doi:http://dx.doi.org/10.4202/app.00066.2014

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