They have nictitating membranes in their eyes, anal fin, and five gill slits. It is the largest order, and its members are also called ground sharks. The species that belong to this order are also called carpet sharks and have two dorsal fins without spines, and some species feature patterns decorating their skin. It is an order of small sized species with spikes on the front part of their dorsal fins.īullhead sharks. The species belonging to this order have a long snout and serrated teeth. This order includes sharks with a wide flat body and pectoral fins, characteristics that make them similar to rays.Īngel sharks. This order includes species characterized by having two dorsal fins and five gill slits.ĭogfish sharks. This classification includes the most primitive sharks, those with six or seven gill slits, a dorsal fin, and lack of nictitating membranes in their eyes. Let’s take a closer look at each of these eight orders and the families that belong to each of them: 1. The classification continues with eight orders, organized in 37 families which include all the species. The scientific classification of all sharks is as follows: Sharks are 470 species belonging to the superorder Selachimorpha. Therefore in each of these parts, the prey behave in different ways which led to the developing of the hunting skills that they acquired. Some sharks dwell at the surface of the ocean and move slowly, other sharks inhabit the pelagic zone and have amazing swimming capabilities and some others stay at the seafloor, in the benthic zone, and move slowly searching for food on the sea floor.Īccording to those areas where sharks live, there are also specific ways of surviving. There are three types of sharks according to the place they live which is closely related to the form and functions of their body. The evolutionary features of sharks, not only defined their look but also the adaptations they have to survive in the wild. An angel shark, on the other hand, has a couple of fins in the dorsal area near the tail and a flat nose with the mouth underneath. For example, the great white shark has the mouth behind its eyes and a large dorsal fin by the middle of its body and a second dorsal fin behind.
Their classification according to the features such as the fin types, spine, snout and body shape determine the genus and family of each species. Their evolution has produced several species with different sizes, anatomies, habits and behaviors. Some shark fossils discovered date back as far as 420-450 million years. However, sharks are far more than this and play a vital role in the oceans and nature. When most people think about sharks, they have a mental picture of a deadly predator. Learning about the world of sharks, knowing their features, discovering their secrets, and recognizing their importance in our world is the first step to their conservation. Even more, many species are docile and harmless. Sharks are complex and fascinating creatures, which are distant from the general representation. They have been widely represented in the popular culture as ruthless predators, which is the main reason why they cause all these different reactions. These unique animals cause all kind of human feelings: fear, awe, curiosity, respect and love. This record-breaking survival cannot be anything but astonishing, developing an anatomy during this time which only has improved over those million years of evolution. The shark species as we know them have been around for 100 million years this means that they were dwelling the oceans when dinosaurs were roaming the land. While they were very different from those found today, sharks have been on this planet for a long time. They belong to the superorder Selachimorpha, and modern sharks have specific characteristics like a cartilaginous skeleton, five or six pairs of gills and several rows of teeth.Īncient Sharks lived before land vertebrates populated the Earth and even before many plant species developed on continents.
Sharks are a large group of fish that have inhabited the oceans for over 400 million years, even before dinosaurs populated our planet.
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