English ELASMO V: Biodiversity

BIODIVERSITY???

Do you know what that is?

Sure, I do!

I can use my long neck to see you in the sea, but there doesn't look like there is much else in the water

Just because you cant see anything doesn't mean there is anything around!

Let me tell you about biodiversity...

It is all the different kinds of life you will find in one area

- DIVERSITY -

Everything that is alive! Even bacteria!

There is a lot of diversity in elasmobraches... I'll show you

Elasmobranchs are separated into sharks (like me!) and rays & skates.

The humans naming rays and skates got confused - ALL skates are rays - but not all rays are skates.

There are over 500 species of sharks and there are more than 630 ray and skate species!!!!

Skate or Ray???

How do we know which is which when some skates are called rays?

Rays have live pups.
Rays have thin whip-like tails (some with stings / barbs on them).

Skates lay eggs (mermaids' purses) with their pups inside.

Skates have fatter shorter tails with two dorsal fins at the end.

Bull ray - this is a ray!

Look carefully! There is a newly-hatched Thornback Ray pup under its eggcase

Thornback ray - this is a skate!

Size
-
Length

Elasmobranchs can be really big!!!

The whale shark is the largest elasmobranch, it
can grow to 18.8m!

And it eats the smallest animals in the water - called plankton!

Size
-
Length

Or elasmobranchs can be really small!!

The dwarf lanternshark is the smallest elasmobranch, only 20cm long!

(Did you know it glows in the dark - that is why it is called LANTERN shark )

Here is a link to a YouTube video "Octonauts and the Dwarf Lantern Shark"

Remember
Press the X on top right corner, at the end, to come back to this story!

Habitats

Some elasmobranchs swim through open water and are known as "pelagic".

Reef manta ray

Blue shark

Atlantic thresher shark

Pelagic stingray