How Many Species of Sharks Are There?
Introduction to Sharks
Sharks are a type of fish that have a cartilaginous skeleton and five to seven gill slits on the sides of their heads. They are found in oceans and seas around the world and come in a variety of shapes and sizes. Sharks are apex predators, meaning they are at the top of the food chain in their ecosystems. They play an important role in maintaining the balance of their ecosystems by regulating populations of prey species.
Sharks have a reputation as being dangerous to humans, but in reality, shark attacks on humans are rare. Most sharks are not interested in attacking humans and will only do so if they are provoked or mistaken a person for prey. Sharks have more to fear from humans than we do from them, as overfishing and habitat destruction have led to declines in shark populations around the world.
Despite their fearsome reputation, sharks are fascinating creatures that are worth learning about and protecting. In the following sections, we will explore the different species of sharks and their unique characteristics.
Classifying Shark Species
Sharks belong to the class Chondrichthyes, which also includes rays, skates, and chimaeras. Within this class, sharks are further classified into eight orders, which are based on their physical characteristics and evolutionary relationships. The eight orders of sharks are:
- Hexanchiformes – sharks with six or seven gill slits
- Squaliformes – dogfish sharks
- Pristiophoriformes – sawsharks
- Squatiniformes – angel sharks
- Heterodontiformes – bullhead sharks
- Orectolobiformes – carpet sharks
- Lamniformes – mackerel sharks
- Carcharhiniformes – ground sharks
Each of these orders contains different families and species of sharks. For example, the Lamniformes order includes great white sharks, thresher sharks, and basking sharks. The Carcharhiniformes order includes species such as tiger sharks, bull sharks, and blacktip sharks.
Classifying shark species can be challenging due to their similar physical characteristics and the fact that many species have not been well-studied. However, scientists continue to study and classify sharks to better understand their evolutionary history and to inform conservation efforts.
Known Number of Shark Species
As of 2021, there are approximately 535 known species of sharks in the world. However, new species are still being discovered as scientists continue to study and explore the oceans. Some of the most recently discovered species include the ninja lanternshark, which was discovered in 2015 off the coast of Central America, and the American pocket shark, which was discovered in the Gulf of Mexico in 2013.
The largest species of shark is the whale shark, which can grow up to 40 feet in length. The smallest species is the dwarf lanternshark, which is only about 8 inches long. Other notable shark species include the great white shark, tiger shark, and hammerhead shark.
Despite being a relatively small group of fish, sharks play an important role in the marine ecosystem. They help to regulate populations of prey species and maintain the balance of the food chain. However, many shark species are facing threats such as overfishing, habitat destruction, and climate change. It is important to protect and conserve shark populations to ensure the health of our oceans and the ecosystems that depend on them.
Undiscovered Shark Species
While over 500 species of sharks have been identified, it is believed that there are many more species that have not yet been discovered. The deep ocean is a vast and largely unexplored environment, and it is estimated that up to 95% of the world’s oceans remain unexplored.
New species of sharks are being discovered at a slow but steady rate, with an average of about 16 new species identified each year. Many of these new species are found in deep-sea habitats that are difficult to study and access, such as the abyssal plain or the hadal zone.
The discovery of new shark species is important for understanding the diversity of life in our oceans and for informing conservation efforts. It also highlights the need for continued exploration and study of the deep ocean to better understand and protect the vast and mysterious world beneath the waves.
Conservation of Shark Species
Many species of sharks are facing threats to their survival, primarily due to human activities such as overfishing and habitat destruction. Some shark populations have declined by as much as 90% in recent decades, and several species are considered endangered or critically endangered by the International Union for Conservation of Nature (IUCN).
Conservation efforts for shark species include measures such as fishing regulations, habitat protection, and education and awareness campaigns. Many countries have implemented fishing quotas or banned shark finning, a practice in which sharks are caught, their fins are removed, and the rest of their body is discarded at sea. Marine protected areas and other habitat conservation efforts are also important for protecting shark populations and their ecosystems.
Public education and awareness campaigns can also help to reduce demand for products such as shark fin soup, which is a delicacy in some cultures and is responsible for driving the demand for shark fins. By raising awareness about the importance of sharks and the threats they face, we can work towards a more sustainable future for these fascinating and important creatures.
