Did you know that sharks are older than trees! They have been on our planet for around 450 million years and have a)_______________ several mass extinctions.
Unlike most fish, sharks have a skeleton made of cartilage and not bone. Cartilage is lighter than bone and much more b)_______________, which allows sharks to be more efficient swimmers.
Whale sharks, which are the largest fish on earth, have huge mouths and about 300 c)_______________ of teeth, but these majestic creatures are docile and feed mostly on plankton.
Not all sharks are massive though. In fact they come in all sizes – the dwarf lanternshark is about the d)_______________ of a pencil!
Sharks have small tooth-shaped ‘scales’ on their skin known as dermal denticles. This is why their skin feels e)_______________ like sandpaper if you were to stroke them from tail to head. These ‘scales’ reduce friction allowing them to swim faster and in fact have inspired f) _______________ for Olympic swimsuits!
Sharks never run out of teeth. When they lose a tooth, it is replaced by a tooth from the row behind. They can go through thousands of teeth in a lifetime.
Sharks have a phenomenal sense of smell, one of the most powerful in the animal g) _______________. They can smell blood from hundreds of metres away.
They are also equipped with special sensory organs which allow them to detect electrical currents and vibrations in the water. This gives them several advantages as hunters. For instance, it can help them detect the heartbeat of h)__________________ hiding under sand.
Not only are sharks fascinating creatures, but they have been a vital part of i)_______________ ecosystems for millions of years. One very important role they play is keeping other animal populations in check (= preventing them from expanding too much). This helps to ensure j)_______________ oceanic life.
Sharks have a k)_______________ reputation thanks in part to movies such as “Jaws” but most shark species are harmless, to humans at least. You are far more likely to be killed by a lightning strike, a bee or even a cow!
Not so fun fact
Alarmingly, shark populations have plummeted by 70% in just the last fifty years, mostly as a result of overfishing, bycatch* and shark finning. 100 million sharks are killed every year.
*Bycatch: the marine creatures caught unintentionally in commercial fishing operations
B) FISH IDIOMS
1. Karla is very nervous about her first public concert. It’s one thing to sing in front of friends and family but singing in front of a big crowd is a different __________ (bucket, kettle, pan) of fish
2. People were packed like __________ (cod, sardines, tuna) in the train so we decided not to get on and to wait for the next train.
3. I wouldn’t talk to the boss today about organising the office party. He’s got __________ (bigger, busier, grander) fish to fry (= more important things to do)
4. Harold needed money fast so he went to a loan __________ (leech, shark, squid) and now he has to pay it all back in a week with 400% interest!
A) a) survived b) flexible c) rows d) length e) rough f) fabrics g) kingdom h) prey i) marine j) diverse k) fearsome
B) 1. kettle 2. sardines 3. bigger 4. shark
a different kettle of fish – a completely different situation
If people are packed (in) like sardines there are so many people in a space that it is difficult for them to move
If someone has bigger fish to fry, they have more important things to do
a loan shark is an illegal and sometimes dangerous lender