Here’s a Quiz from Ruth’s latest talk on marine life. We are learning lots and hoping for more sightings as the seabed shallows around Barbados. (Answers after the questions. How much do you know?)
1. What are cetaceans?
2. What are their common features?
3. Name the two groups they are divided into?
4. From what type of creatures, when and how did they evolve?
5. What is the closest land relative of cetaceans?
6. What are the nasal organs called that produce the clicks in echo location?
7. What are the large plates (made out of keratin) that large whales have to filter out their food from the water?
8. What is the muscle protein called that binds to O2 allowing more O2 to be stored in the muscle for diving?
9. Name at least five diving adaptations that whales have?
10. What is the process called that Humpback Whales use to herd together and consume fish?
1. Whales, dolphins, porpoises
2. They are mammals: they breathe air, are warm-blooded, give birth to live
young and they suckle their young. Common features: they are streamlined,
they have fins and blow holes.
3. Toothed (odontocetes) – have teeth
Baleen (Mysticetes) – have baleen plates
4. They evolved from small terrestrial mammals that existed on earth around
fifty million years ago. Over time some of these animals became more and
more adapted to an aquatic lifestyle, with their front limbs evolving into
flippers, their tails developing flukes. Eventually their back limbs were
lost (although two small bones either side of the pelvis still exist today)
and their bodies became elongated, making them more stream-lined in the
6. The clicks are produced by the phonic lips and sent out in front of the
animal. This then bounces off an object and returns to the lower jaw of the
animal as an echo.
7. Baleen plates.
8. It is Myoglobin. The blood is thick and viscous so that there is a high
percentage of O2 stored in red blood cells. The myoglobin protein is ten
times more concentrated than in human muscles. (The Whale meat of
deep-diving species appears as almost black). The myoglobin is positively
charged so that it does not clump together in the same way as it does in
humans and the highest concentrations occur in muscles needed for swimming.
9. They have a folding rib cage.
They exhale large amounts of air from their lungs before diving.
They shunt blood from their extremities to the brain, heart and muscles.
They have a lower heart rate.
They store O2 in blood and muscles.
They have a high blood to body volume ratio.
10. Bubble netting
I hope you got 10/10. Sammy just did, when I tested her. We are on our way to Bequia, so morale is very high today. All we need is a whale or a few dolphins and our happiness will be complete!