Whales are majestic aquatic animals that can be either toothed or equipped with baleen plates, whereas blue whales solely have baleen plates. Besides, blue whales have a distinct blue-gray coloring, unlike most whale species that carry darker hues. In addition, blue whales have smaller dorsal fins than most whales. 

Fin whales and blue whales belong to the Balaenopteridae family and are known for their large size, grooved chest, unique dorsal fin, and unfused cervical vertebrae. There are several points of similarity between the two species but they also differ in terms of coloring, appearance, and general habitat requirements.

Some sharks swallow their prey without needing to chew. Other shark varieties, like the Port Jackson Shark, grind the prey using their broad back teeth. Some sharks are also filter feeders. When eating large prey, sharks injure them first to bring them under control and then use their teeth to bite and grind their prey. 

Sharks are known to bite. However, it is incorrect to believe that they are biting machines. Some of their species, such as Great White Sharks, are aggressive, yet they don’t attack and bite to be aggressive. Shark attacks on people are quite uncommon. Nonetheless, they do bite through their prey to satisfy their hunger.

There are another shark species known as the “living fossils,” the goblin sharks. These sharks, which belong to the mitsukurina family, are the only surviving family member and have evolved during the early cretaceous period, dating back 125 million years. They are one of the strangest-looking sharks.

Sharks, like fishes and cetaceans, have fins. These fins stabilize the shark and help it stay afloat in the water as well as move forward. Without their fins, sharks won’t be able to glide through water or hunt for their potential prey. Therefore, fins play a crucial role in facilitating the shark’s movement.

Among their many other amazing adaptations, sharks are best known for unique tongues. The mouths of sharks contain structures resembling tongues. Unfortunately, they are not true tongues. These are bony projections in sharks’ mouths, also known as basihyals. They look like tongues while being not tongues at all. This is probably because a shark’s taste buds aren’t located on its tongue. 

The skeletal system of a shark, on the other hand, is constructed entirely of cartilage. These fish are called “elasmobranchs,” which means “fish with cartilaginous tissues.” As a result, their entire body comprises a more elastic and flexible alternative to bones, making them much lighter and aiding in buoyancy.

It’s worth noting that sharks prefer to stay away from dolphins. Despite their cuteness and reputation for being playful, dolphins pose a hazard to these fishes. Dolphins are highly effective fighters who can easily defeat sharks in a fight. Sharks prefer to avoid Orcas, the largest dolphin family species known to hunt sharks.

Sharks, like other fish, are classified vertebrates, meaning they have a backbone. Therefore, sharks share the same spinal column as humans. However, the great surprise is that there is no indication that the vertebrae are comprised of bones. This is what distinguishes this fish.