8 Shark Facts You Might Not Know
People might first think of sharks as ruthless killers or associate them with the killing scenes in the famous movie 'Jaws'. However, few people realize that we still don't know many mysteries about sharks. For example, they are not as scary as people imagine, and they are not necessarily hostile to humans; they also don't necessarily live in the ocean. This time, V will introduce you to 8 shark trivia you may not have heard of.
1. Not all shark species live in the ocean
In the thoughts of many people, it is generally believed that sharks only exist in the ocean, but the fact is not always the case. Not all shark species live in the ocean. You can also see them in some freshwater lakes and rivers. For example, great white sharks are used in tropical rivers. But they are not afraid of seawater. Rivers in New Guinea, Australia, and South Asia are shark homes.
2. Sharks can hear sounds 230 meters away
Sharks are always known for their sense of smell, but their equally impressive hearing is also impressive. They can hear sounds 230 meters away. They can even capture the sound of prey’s muscles moving.
3. The tiger shark doesn't picky, will swallow human garbage
The tiger shark doesn't picky, they will settle for almost all that happens in the water, including Barbie dolls, car license plates, tires, and rubber shoes. Therefore, these sharks are also known as ‘ocean garbage cans’.
4. Shark's bones are not bones
Have you ever wondered why shark teeth fossils are often found, but bone fossils are rare? The reason is simple. Unlike humans and most other vertebrates, sharks and their relatives do not have bone-based skeletons. Their skeletons are made of cartilage, just like your nose and ears, which is smaller and more flexible, but it rarely turns into a fossil like bones because it is not mineralized. It is actually made of cartilage and muscle, with a density much lower than bones. However, this is also the reason why they can become such excellent swimmers and be able to turn sharply.
5. Sharks may be older than dinosaurs
Scientists believe that sharks have existed for about 4.5 million years, and their ancestors are a fish called placoderms, which look like small sharks but have different fins. The earliest fossil evidence of sharks or their ancestors dates back to the late Ordovician period about 4.5 million years ago, while the earliest dinosaur fossils appeared more than 2.35 million years ago.
Museum fossil fish curator Emma Bernard says: ‘Fossil-like scales from the late Ordovician period have been found, but no teeth. If they come from sharks, it indicates that the earliest form may be toothless.’ However, scientists are still arguing whether these are true sharks or class sharks’.
6. Sharks can grow up to 30,000 teeth in their lifetime
Sharks have teeth in rows, and they can grow up to 30,000 teeth in their lifetime. According to different species, there can be up to 15 rows in each jaw. The front teeth are the strongest, while the back teeth are smaller. Because they don't root firmly like human teeth, sharks often lose teeth, but unlike humans, they can regrow new ones’.
7. Sharks and humans have a common ancestor about 44 million years ago
Although there is a huge difference between humans and sharks, there are still some scientific evidence to show a connection between humans and sharks. For example, the shark genome is very similar to the human genome’.
8. People die by selfie more than sharks
Everyone often describes sharks as very scary and bloodthirsty animals that love to attack humans. But in fact, the number of people killed by sharks is even lower than the number of people who died from selfies that look completely harmless. The Indian Family Medicine and Primary Care Journal found that between 2011 and 2017, 259 people died in 137 selfie-related accidents, while only 50 people were killed by sharks’.
