Sharks don’t have a skeleton. They have a skeleton made of
cartilage. It’s the same kind of stuff you have in your ear. It makes them very
flexible. The only bones they have are their jaws and teeth. That’s why it’s
hard to find fossil sharks.
A sharks skin is amazing. If you rub its skin from front to
back (be sure to avoid the teeth) it feels fairly smooth. If you rub its skin
in the other direction, from tail to head, it feels very rough. In the old
days, carpenters used to use it as sandpaper! This kind of skin helps them
glide through the water.
Most sharks are cold blooded, which means they are the same
temperature as the water around them. Great white sharks can raise their body
temperature by moving their muscles. This lets them survive in colder waters and
stay active.
Sharks are very helpful for the ecosystem. In coral reefs they are important in keeping fish populations under control. Otherwise all those fish might eat the whole reef and kill the coral.
I hope you liked the sharks!
Love, Papaw
If you would like to know more about sharks, here are some helpful
sites.
More Information:
https://www.worldwildlife.org/species/shark
https://www.montereybayaquarium.org/animals/animals-a-to-z/sharks











