During your diving in the ocean, have you ever told your family and friends that you had spotted a shark, then later found out that it was just another marine animal and not a shark? Well, it happens to us all, and in the excitement, we often fail to recognize a shark. Having said that, if you go into the water, it is of utmost importance that you are able to identify a shark.
The sharks do not necessarily seek out humans, but they do pose a threat. If you cannot classify whether it is a shark or not, you are putting yourself at greater risk.
Oceans around the world inhabit sharks, and they have been living there for a long time, even longer than trees and dinosaurs. Over 500 species, sharks are important for the healthy oceans as they keep the population in balance and as well as maintain the food web.
With that said, seeing sharks is always a pleasurable experience, and it is even more satisfying watching sharks jumping out of the water. Not to be surprised, sharks play a pivotal role in boosting eco-tourism. Shark diving, tours, and all recreational water sports become truly adventurous and mesmerizing, all thanks to the sharks.
But the problem remains, how to identify sharks? What if one crosses by, but you miss a sight thinking of it as some other animal?
Not anymore, since this blog will let you know the important points that will help you identify sharks even from a distance. So do read it out if you don’t want to miss the next chance to see and capture the moment.
As an initial thought, we all considered sharks to be giant-sized toothed animals, but in reality, you will find sharks of varying sizes, colors, and shapes, because there are over 500 species of sharks found in the world.
With that, the features and characteristics vary from species to species, however, there are certain elements that are the same for all sharks. We are going to determine that and will also see some of the well-known shark species distinguishing features so that you can easily identify them.
Sharks Physical Appearance
Sharks have been here for ages, and they will be here for many years to come, but when it comes to physical appearance, it is believed that sharks haven’t changed much. The physical characteristics alone will help a lot in shark identification.
There are no bones in a shark, so their skeletons are cartilage and connective tissues. They have a muscular, irregular, inverted tail, pointed fins, and a snout.
The teeth are not directly attached to the jaw but are embedded in the gums and are replaced from time to time.
Dietary habits determine tooth shape: sharks that eat mollusks and crustaceans have dense, flat teeth that are used for crushing, while sharks that eat fish have needle-like teeth for better gripping. Why not find what is included in the shark’s diet? Sharks that prey on large mammals have stronger teeth with an upper tooth with a serrated edge that can cut through larger prey and pointed lower teeth for grasping.
Shark fins are another physical aspect that helps you differentiate between the creatures. The five different types include the pectoral fins, pelvic fins, dorsal fins, anal fins, and caudal fins (tail). While most sharks have eight in total, some may have six or seven. The primary function of the fins is to propel the shark through water by providing drive, firmness, steering, and propulsion. Do read about how sharks swim, and you will know the functions in detail.
Identification of Some Well-Known Sharks
Knowing about the physical appearance, in general, would have given you an idea of sharks’ body parts and what they will look like. But as said earlier, significant differences can be seen with different species types. So, let’s explore the common shark species and how you can identify them easily.
The Great White Shark
It is said to be the largest shark species, approximately 20 feet in length. The size itself is enough to give you an idea; however, the conical snout and triangular dorsal fin will further allow you to recognize the great white.
Moreover, an unexpected color change on the flanks makes them easy to recognize. Their tops are dark grayish-black, while their undersides are very pale and almost white.
Tiger Shark Identification
Reaching a length of about 15 to 18 feet, tiger sharks are recognized easily with their low interdorsal ridge, rounded snout, and serrated teeth. Moreover, tiger sharks are said to have spiracles that allow them to stop at a particular position for a period of time. Moreover, the body of a tiger shark is striped with dark lines, which resemble stripes on a tiger, but these fade as the shark grows older.
Bull Shark Identification
The distinguishing characteristic of a bull shark includes the difference in the size of dorsal fins. Reaching an approximate size of 10 feet, bull sharks are aggressive in nature and are involved in a number of attacks on humans. Furthermore, the bull shark lacks an interdorsal ridge, but it has a shorter snout and smaller eyes.
Features which make Sharks Exceptional Creatures
Not all sharks are similar but there are some of the unique features that are common in all of them and make them distinctive from the other ocean creatures and help to correctly identify the shark’s species. Here is the list of unique features of sharks.
1: Sharks have fusiform body shape
First and foremost, sharks were identified on the basis of their body. Typically sharks have a fusiform shape of the body, meaning rounded from both ends, this shape of sharks helps them to swim deep in the ocean and requires a minimum amount of energy. However, some sharks have flattened body shapes like angel sharks and wobbegong sharks have extremely flat body shapes.
2: Sharks have different pairs of fins
Fins are the rigid structures which are supported by rods made up of cartilage; most sharks have 5 pairs of fins,
- Caudal fins: The movement of caudal fins helps sharks to move in forward and backward directions.
- Pectoral fins: The pectoral fins provide lift towards the front region of the shark’s body and stabilize the downward force produced by caudal fins
- Pelvic fins: These fins are responsible for providing stability to the body of sharks
- Dorsal fins: The pair of fins also stabilizes the body of sharks and have a spine, thus having a defensive role.
- Anal fins: These are also responsible for providing stability but this pair of fins is not present in all these species of sharks.
3: Sharks possess multiple pairs of gills
Sharks can be identified on the basis of the different pairs of gills they bear, most species of sharks have 5 pairs of gill slits but some may have 6 pairs or even others have 7 pairs. These pairs of gill slits are located on the side of their head, the gills are covered with tiny membranous structures that extract oxygen from the water, which is utilized by sharks for respiration as sharks do not use atmospheric oxygen to respire.
4: Sharks bear unique electroreception organ
Sharks bear a special type of electro-receptive organ called Ampullae of Lorenzini, these are the small jelly-like pores that are located around the head, near the nostrils, or underneath their snout. These sensory organs help to detect the electric field produced by other animals in the ocean water, the electric fields help the shark in navigation and to locate their prey or enemies far away from them.
5: Sharks have multiple rows of teeth
One of the most important features that make sharks distinct is their jaws and teeth. Sharks possess multiple rows of teeth that continue to replace one after the other and are lost completely but do not have jaws attached to their head. The teeth of sharks are considered remarkable because teeth were the only part of their body that has been fossilized or remained intact for thousands and millions of years ago and provide knowledge about their evolutionary history as well.
6: Shark skin bears dermal denticles
As you know that sharks do not have bones so to keep their body in accurate shape, the skin of sharks is usually hard and tough and bears small scales like dermal denticles which help in reducing the friction and resistance between water and sharks so that they can easily swim in the ocean without using much energy. Moreover, the denticles grow in size as the size of shark’s increases and also protect the skin from injuries.
7: Sharks’ tails have unique patterns
Sharks can also be distinguished by various patterns of their tail, all species of sharks have quite unique designs of tails. The tail of sharks helps them to swim faster and provide balance when they are in motion so that they can slide elegantly to different sides. Their tail is made up of cartilage so it gives them a very smooth and flexible movement when they swim or float.
8: Sharks have skeletons made up of cartilage
The skeleton is another feature that differentiates sharks from bony fishes and other terrestrial vertebrates. The shark’s skeleton is made up of cartilage and connective tissues, the cartilage is flexible and sturdy which reduces the weight of the skeleton and thus saves sharks energy when they swim in deep oceans. Moreover, the skeleton also provides protection to ribs because the ribs are without rib cage so there are high chances that they could be crushed easily by their own weight.
9: Sharks have a large liver
Most fishes in the aquatic ecosystem have a swim bladder filled with air which provides them buoyancy when they swim but it’s not the same in the case of sharks, they have large livers filled with oil droplets which reduce the density and give sharks a hydrostatic lift when they are swimming. The weight of the liver could make up to 25% of the total weight of the shark’s body, they usually store fats in the liver which provides them energy when they have to travel long distances.
10: Sharks have well-developed sense
Sharks have very well-developed senses used for hunting as well as communication:
Vision: The structure of the shark’s eye is remarkable, the size of pupil changes in response intensity of light. They have rods to sense light or dark spectra and cones which help them to see different colors, a layer of tapetum lucidum is present behind the retina which aids them so they see much better in dark, cloudy water or deep in the sea at night.
Taste: Although sharks do not have a very robust sense of taste, the taste buds located in the mouth and throat allow them to taste their food before they swallow it. This avoids the intake of dangerous prey items, which might have a bad taste.
Smell: As they swim, water passes into their nostrils and across sensory cells, they are able to distinguish different chemical signals produced in the water by other animals. A nostril of sharks can also detect smells and depict the direction from where the smell is coming.
Hearing: Sharks have two-minute openings on their head or behind and above their eyes that leads to internal ears. These sensitive cells help sharks to detect low-frequency sounds and to capture suitable prey swimming and flapping in their vicinity.
Touch: Sharks do not have fingers but they possess lateral lines running from head to tail, these lines can also be used to feel and touch. The lateral line bears small pores that allow the flow of water through the shark’s skin, these pores are called “neuromasts” that can sense different vibrations in the water.
A shark is one of the many marvels of the marine world, and to your surprise, they have many distinct features which allow you to easily identify them even from a distance. Sharks play a pivotal role in maintaining healthy blue oceans as well as enhancing eco-tourism, but what if you aren’t able to recognize a shark even if it’s in front of you? Well, that would be awful. But, this article has provided you with enough info to easily identify sharks.