Sharks & Rays - THEY ARE FISH! (gills and paired fins)

Sharks and Rays Together in a separate group of “fish” because they lack bones. No “bones” at all!!! – all cartilage

Rays are just flat sharks.

Ray anatomy – they can flap, (sharks can’t flap their fins) Ray anatomy – they can flap, (sharks can’t flap their fins)! Notice they have pectoral AND pelvic

Most rays are bottom feeders, a few are plankton eaters

Some have stingers, some don’t When at the beach, do the “sting ray shuffle!”

Guitar fish/ saw fish - half/half

Sharks: Lots of variety

Sharks use to be BIGGER Megalodon!!!! Vs Great White

If you caught a megalodon

Hardest part of a shark TEETH roll out like conveyer belt, shed easily and easily found on beaches if you know what your doing.

Sharks have jaws that are extendable – like other fish

Shark’s top jaw is normally hidden in a fold in his lip,

Sharks & Rays have very good electro-reception - notice nostril also

Why sharks bite surfers (though it is really rare) They were attracted to the board in the movie, but they don’t attack it… why not?

Most fish swim with mouth slightly open… why Most fish swim with mouth slightly open… why? But sharks often swim with their mouths closed because they have a “spiricle” -

Sharks/ rays – no Swim bladder 1 – liver is oily and huge, 25% of it’s weight, up to 90% of the belly area in some sharks… & … oil floats, so that helps 2 – if they stop swimming they have trouble floating.

Shark/ ray have a slit for each gill arch instead of a operculum over all gills

Male sharks… have … male parts Sharks have internal fertilization

Shark reproduction Most sharks are just “normal”.. .meaning there is very little hermaphrodites in the sharks Most sharks are oviparous – though some are ovoviviparous, and very few are viviparity. Shark eggs are like leathery pouches – with different designs and colors

Shark skin – placoid scales (most fish have ctenoid) Placoid scales are made of the same thing teeth are made of!

Who eats sharks? Do they have natural predators?

Shark fin soup debate

They look mean… but if you can flip them over! = They look mean… but if you can flip them over!

Why shark meat might taste different. MOST fish have blood that is salty… just like ours, but not as salty as the ocean. They have to actively keep salt out and water in. Sharks don’t bother… they are “ISO-OSMOTIC” TO SALT WATER. Which means their blood and meat has lots of salt in it. The primary salt they use is “urea”… to keep their blood salty.