Question

The sperm whale is also the second deepest diver. Why is it paradoxical that the species with the largest brain on earth is such a deep diver? In your answer, include systems, tissues, cells and subcellular components involved as well as metabolic rate and homeostasis.








How does this species accomplish this feat physiologically?

Answer 1

Sperm whales range across the open ocean, but they typically gather at deep canyons, to socialise, mate and hunt food sources no other predator can reach. They dive up to 10,000 ft under the ocean surface, hunting for fish and giant squid. A sperm whale detects its prey by sending echolocation clicks from the front of its nose and listening for the echo, which reverberates in a fatty sac beneath its mouth. This enables it to pinpoint a single squid from thousands of feet away. Sperm whales spend most of their lives in the darkness because they hunt in a part of the ocean where light does not reach. They use these clicks as a visual tool to see and analyse what's around them. They perceive the world through sound.

Sperm whales have the largest brain of any living animal. At 8,000 cubic centimetres, it is over five times the volume of ours, a comparably minute 1,300 cubic centimetres. Their neurological processes are far more cemented in evolutionary history. The human brain has changed markedly over the past million years, and we have only had the big brains we do now for about 200,000 years. In contrast, the current size of the sperm whale brain has changed little from that of its cetacean ancestors, which evolved some 55 million years ago.

In addition, the sperm whale cortex contains neurons called spindle cells. These long, straggly structures are found in humans and only a small handful of other species. They are thought to allow for rapid communication between distant brain regions, as well as allowing us to feel love, process emotions, interact socially and feel empathy for others. All this suggests that sperm whales are pretty adept thinkers.They spend much of their time prowling thousands of feet below the ocean surface in search of food. They are also easily spooked and avoid submarines, underwater robots and humans in scuba gear. But they do come to the surface to breathe and socialise. Sperm whales go down to much deeper depths and back up several times a day. One big factor in the whale's favor is that they are holding their breath while human divers are breathing compressed air.

Most sperm whales only have teeth in the bottom jaw. Some males have a few teeth in the upper jaw. The lower jaw usually has 20 to 25 pairs of large (10 inches long) teeth. The lower jaw can be opened very wide to 90 degrees. The jaw can be over 3 meters long. Inside every whale flipper (or pectoral fin), is a cute collection of bones that look suspiciously like a human hand - complete even with thumb bones. They are probably the deepest air-breathing divers on the planet. They have the biggest head for their size of any animal (up to one third of their body length).Sperm whales apparantly have the biggest brain (9 kg or 20 pounds) of any animal that has every lived on this planet. They are almost certainly the largest toothed predator that has ever lived, and they have the biggest teeth (10 inches long). It is thought that sperm whales have the lowest reproductive rate of any animal - not necessarily a good trait. Sperm whales carry in their great huge heads the world's largest natural sound producing organ (unfortunately for them this organ is full of a fat called spermaceti that was once very popular amongst humans for making a high grade oil). The difference in size between male and female sperm whales is the greatest of all the cetaceans. The females are only two-thirds the length, and one third the mass, of the big males. The tail-flukes (tail flippers or tail fin to we land-lubbers) are the largest with respect to the whale's size of any of the cetaceans. Flukes up, ready for a powerful downward thrust. The tail-flukes of the sperm whale are more flexible than most whale flukes. This may make them more efficient at slow speeds.

More myoglobin in a muscle means more oxygen can be stored in that muscle. Sperm whale muscles are almost black they contain so much myoglobin. Molecules called myoglobin store oxygen in muscles. They hold onto oxygen molecules until they are needed by the muscles. Different animals and different muscles can have different amounts of myoglobin. The more myoglobin in the muscle the darker the muscle will be. Molecules called myoglobin store oxygen in muscles. They hold onto oxygen molecules until they are needed by the muscles. Different animals and different muscles can have different amounts of myoglobin. The more myoglobin in the muscle the darker the muscle will be.

To stay warm and also have enough energy to hunt and reproduce, they needed to grow to large sizes and so that they can produce more energy in their bodies. When they grow larger, meaning it has more volume, it's volume-to-surface area ratio is smaller, so it will stay toastier and are typically hotter than smaller animals. But they can't completely supersize themselves because as they get larger, their metabolism increases, and it's challenging to eat the food needed to sustain such a giant body,