Jefferson County Public Library Logo

Teen Blog Archive
Home >Teen Blog Archive

JCPL Teens

MARCH 16, 2013
Science Saturday - Sharks!

"Great white shark, or white shark (Carcharodon carcharias)." Gale Science in Context. Detroit: Gale, 2010. Science In Context. Web. 16 Mar. 2013.

Sharks date back to the time of the dinosaurs.  They have a reputation as being the great killers of the ocean but this is not necessarily true.  The largest shark is the Whale Shark which can be as long as 59 feet.  This shark is extremely gentle and feeds on zooplankton.   The smallest shark species is the Dwarf Lanternshark which can fit into a man's palm.  According to the Science in Context Database: " in the year 2012 there were eighty confirmed unprovoked shark attacks on humans world-wide. This included fifty-three attacks in U.S. waters, mostly occurring off beaches in Florida."

All sharks are cartilaginous.  This means their skeletons are made completely of cartilage.  Unlike fish, sharks don’t have scales, but rather spiny projections known as denticles. Sharks also have a third eye, called a pineal eye, which is used to sense light. 

Fish have air bladders that allow them to float in the water but sharks do not.  Most sharks must be in constant motion to stay afloat.  One thing that does help them stay afloat is their fatty liver.

   Add a Comment
Enter your comment below, then click Submit.
Nickname: (displays with your comment)
Enter the letters you see on the left:



Powered by  Powered by

Blog Guidelines
We want to hear from you! Keep in mind when posting comments that anyone can read what you have to say. Please do not include personal information, such as your last name, phone number or address when replying to our blogs.

Spam, profane language, personal attacks or inappropriate comments will not be posted, and we reserve the right to edit or delete any comments that violate these guidelines.

If you already use an aggregator like Bloglines to keep track of your favorite blogs, be sure to add our RSS news feed to your list.

Thank you!

top | back | home

Go Mobile! | Contact Us | Policies/Legal Notices | Using Online Resources | Site Index | JCPL Facebook Page JCPL on Twitter
©2010 Jefferson County Public Library • 10200 W. 20th Ave., Lakewood CO 80215 • 303-235-JCPL (5275)