Q&A 5 - Many Shark Questions

Megan wrote - "Hey SharkyJones this is megan again and i have a bit of questions i would appreciate if u would answer for me please.

QUESTIONS
1.What is the biggest size of a great white shark?
2.What all shapes of teeth on sharks are there?
3.Do all sharks change colors?
4.Is there a certain time or place or anything when a sharks behavior changes?

I read about the feeding style or what the sharks eat but i didn't see a few of the sharks but i am more or less interested in about 3 certain sharks in all of the sharks. they are.
1.Great White Shark
2.Whale Shark
3.Hammerhead Shark
and if u could give me more information about these sharks i would like it cause they are my favorites.

I would also like to know a personal question to u.
1.Have u ever touched a shark?
2.Have u swam with a shark?
3.Do you own any sharks?

I think sharks are really cool and i cant wait to be a lil older and be able to go like scuba diving or something and touch a shark and swim with one and find out what they are really like up close since everybody always thinks of sharks as DANGEROUS well i don't i want to meet one up close and personal.
so thanks for helping me again and i know i am going to appreciate this afterwards.
p.s. Do u know anywhere to go scuba diving to see sharks or anywhere to go to be able to pet them or anywhere to go just like a aquarium or something sharks have become really cool to me and mabye even my favorite animal or second favorite animal. thank you very much megan H.

SharkyJones Says :

"Phew!, Quite a lot of Questions there Megan and some very good ones too! - I'm going to answer this in bits, there's a lot of stuff there."

Let's try to answer these 1 at a time :

1. What's the largest Great White ?

This is always a bit of a debate, since several large Great Whites have been captured around the world but there are many discrepancies in size. The largest GW caught of the Atlantic coast of the USA, was according to the Smithsonian Institute - August 7, 1986, it was 5.1m long (16ft 9 inches), weighing 1,556kg (3,427lbs).

The largest reliable record I can find, again from the Smithsonian was taken of Cojimar, Cuba in 1945 at 6.4m (21ft Long) and 3,324kg (7,300lbs).

There have been reports of a 23ft long Great White caught off Malta several years ago, some people believe that there is evidence that they can get up to 25ft in length, though this is unlikely to be proven. The average size for a great white is somewhere between 12-15 feet. They are thought to grow about 20cm per year in the Atlantic, although in the Pacific its thought that the younger sharks grow at 25-30cm per year to 22cm as they grow older. So a 16ft white shark from the Atlantic is estimated to be 20 yrs old and about 13 to 14 yrs old in the Pacific.

Link 1 - Great Site on Sharks

Link 2 - Another great shark site

2. What shapes and sizes of shark teeth are there?

Simple answer - LOADS!

The shape and size of sharks' teeth varies massively according to how they've adapted to the type of prey and the lifestyles they lead.

The biggest teeth come from the now extinct shark Carcharadon Megladon, this shark existed up until about 25,000 years ago and probably looked like a Great White, but could grow up to 40 to 60ft, the biggest fossilised teeth of this species that have been found are about the size of a sandwich plate!

The shape of the teeth is influenced by the animals that the sharks prey apon :

Great White Sharks - When they're young they eat fish, as they grow older their teeth grow more triangular and serrated (notched) to bite chunks out of the tougher flesh of large tuna, seals and dolphins!

The tooth on the left is from the upper jaw while the tooth on the left is from the lower jaw (although when younger their teeth are narrower). The difference between upper and lower teeth is common to many sharks. This is because when a shark bites it extends its lower jaw and brings the lower jaw up to stab and hold the prey, like a series of forks, the upper jaw extends outwards and rakes back in a line, working like a knife making a cut while the fork holds the meat steady - see sharks have table manners too, but they are messy eaters nonetheless!!

Bull Sharks and Oceanic White tips also have very triangular teeth, again both will prey on larger tougher prey. Oceanic whitetips often follow whale pods and will eat the carcasses of dead whales.

Oceanic Whitetip Teeth (Carcharhinus Longimanus)

Other sharks like Makos and Sand Tigers tend to eat fish which they must catch in the open ocean. Their teeth tend to be longer and finer, more like a series of forks than the triangular "knives" up above. Although these teeth are made more for grabbing smaller fish they are also capable of tearing, I've seen a 7ft sand tiger grab a 2.5ft jack about twice the size it can fit in its mouth, it grabbed it, shooks its head hard and cut it in two.

This is a mako tooth, long and smooth on the side.

Tiger Sharks have probably the most interesting teeth of all! Tigers eat just about anything they can find. A favorite food is Sea Turtle, obviously those guys have a tough shell and tough meat that the shark has to bite through. Tigers will also eat fish, dead whales, dolphins if they can catch a sick one.

Tiger shark teeth are heavily serrated with a point to stab but also a long edge out the side with which to cut! Check this out!!!

Pretty Awesome huh!!

BUUUUT!!

If you think that's cool, check this out - Remember i talked about Megladon the ancient shark like a great white that could grow to 60ft. Well this is a tooth from one that has been fossilised!

There's no sense of scale, but I happen to know that this tooth is 5 3/4" long so to put the 1 3/8" Great white tooth next to it to scale, I've scaled the GW tooth and the oceanic whitetip down to scale. Remember the Oceanic Whitetip tooth is 1 " long and is scaled relative to the other teeth!!.

You can pretty much fit 4 people into the mouth of a Megladon!

This megladon tooth is 14cm long!

3. Do all Sharks change colour ?

Well actually very few sharks change colour. You might be thinking instead of Squid, Octopi and Cuttlefish (a group of animals called Cephalopods), they can change colours and skin texture very rapidly, cuttlefish are so amazing that I've watched them run stripes up and down their body like watching a tv, I felt I could have attatched a television tuner and watched football!

But you are right, some sharks do change color a little though its rare, though there are many different colours and patterns that different sharks have naturally, though these colours don't change much.

Here are some sharks that change colour at different parts of their lives :

Tiger Sharks

Zebra Sharks

These are some sharks that have some wacky patterns that they keep throughout their lives

Leopard Sharks

Catsharks

Swellsharks

Hornsharks

And these are a couple of sharks who have been known to change their colours depending on their environment rather than their normal natural coloration.

Bonnethead shark

Golden Hammerhead